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Dive into a comprehensive collection of 1715 Java interview questions, ranked by their likelihood of being asked, derived from a analysis of 600 public interviews on YouTube.

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Java Interview Questions

A curated list of 1715 Java interview questions, sorted by their frequency of being asked.

Methodology: 600 public interviews on YouTube were analyzed, and thousands of unique questions were gathered from them. The analysis utilized voice transcription and text categorization techniques. The frequency of each question was then counted, and the probability of each question being asked was determined.

Videos

Table of Contents

Translations

For international readers, I've translated the questions to various languages:

Each translated file follows the same structure as the main list, but in the respective language.

Questions List

High Occurrence

Question Category
Tell me about yourself General
What is OOP OOP
What is the difference between Checked and UNCHECked exceptions Java Core
What methods in the Object class do you know Java Core
Tell me about the hierarchy of exceptions Java Core
What is Solid General
Tell me about the hierarchy of collections in Java Java Collections
What is the difference between the interface and the abstract class Java Core
What is the difference between Linkedlist and Arraylist Java Collections
Tell me about Hashcode and Equals Contract Java Core
What is the difference between a primitive and a reference type of data Java Core
How Hashmap is organized Java Collections
What is you experience is in programming General
What do you know about Object class Java Core
What are the principles of OOP OOP
What is ACID Databases
What is Stream in Java? Java 8
What Spring Scopes do you know Spring
What is a functional interface Java 8

Moderate Occurrence

Question Category
Tell me about Deadlock Multithreading
What is executorservice Multithreading
What are Hashcode and Equals overwritten rules Java Core
What is the normalization of databases Databases
What is the difference between SQL and NOSQL Databases
What is Lambda Java 8
What are indexes Databases
What is Bean Spring
What is the idea of multi -seating Multithreading
How Hashmap is related to SET Java Collections
Tell me about Race Condition Multithreading
What is the difference between final vs Finally vs Finalize Java Core
What primitive data types are in Java Java Core
What areas of memory in JVM do you know Java Core
Familiar with SQL SQL
Why do you need a class Object Java Core
What design patterns do you know Patterns
How Singleton differs from Prototype Patterns
What is polymorphism OOP
What is a process and a stream, how they differ Multithreading
Are you familiar with SQL SQL
What is the life cycle of Spring Beans Spring
Tell me about Hashmap Java Collections

Low Occurrence

Question Category
What is Hibernate Hibernate
What is the difference between JDK and Jre Java Core
What is Hashcode Java Core
What is a string pool Java Core
What is an iterator and why it is needed Java Core
What is the difference between the MAP operation and Flatmap Java Core
What types of data are in Java Java Core
What is ORM Frameworks
What is encapsulation Java Core
What is the main idea of Equals and Hashcode Java Core
Why is singleon called antipattern Patterns
What is the difference between Left Join from Inner Join Databases
What are access modifiers and what are they Java Core
What do you know about String Java Core
What are how many normal forms exist in SQL Databases
What is an exception Java Core
What is optimistic and pessimistic locks Multithreading
What is a monitor Multithreading
Why do you love or hate Java General
What types of Join do you know SQL
What is the difference between Having and Where SQL
What is the difference between hashmap and hashtable Java Collections
What is a keyword Final Java Core
What is Spring context Spring
What is the difference between Treeset and Hashset Java Collections
What scopes do beans have Spring
Why MAP stands apart in the hierarchy of collections Java Collections
What is the difference between Dependency Injection and Inverhuron of Control Spring
Why do you need Spring Framework Spring
How is Rebase different from Merge? Git
What is Finalize Java Core
Is it possible to override static methods Java Core
What makes the key word transient Java Core
What is the difference between Supplier and Consumer Java Core
What is the idea of polymorphism Java Core
What do you know about the Clone method Java Core
What is the idea of Stream API Java Core
How can I implement multiple inheritance in Java Java Core
What does Garbage Collector work with Java Core
What is a line in Java Java Core
How the Try With Resources operator works Java Core
Can a primitive data type to get into HIP Java Core
What methods are located in the interface Java Core
What is the relationship of the Equals and Hashcode contract Java Core
What are the principles of Solid General
Stringbuilder and Stringbuffer, what are the differences Java Core
What do you know about the Java 8+ functional interface Java Core
Why is it impossible to compare objects through "==" Java Core
What types of data exist in Java Java Core
The main idea of encapsulation Java Core
What is the meaning of incapsulation Java Core
Why do you need String Pool Java Core
What is Parallel Stream Java Core
What is String Pool Java Core
What design templates do you know Patterns
What are the advantages and disadvantages of the OOP compared to procedural and functional programming OOP
What is JVM, JDK, Jre Java Core
What is MOCK in testing Tools
What is Volatile Multithreading
What is Completablefuture Multithreading
How to create a stream Multithreading
What is partitioning Databases
Describe the principle of Happens Before Multithreading
What design patters do you know Patterns
What is synchronization and why it is needed Multithreading
What are the advantages and disadvantages of the OOP compared to procedural and functional programming OOP
What are the states of the object in Hibernate Hibernate
What is Future Multithreading
What is the difference of Char and Varchar in SQL Databases
Tell me about the Collection Framework hierarchy Java Collections
What is JDBC Tools
Array of static data structure or dynamic Java Collections
What is the difference between Arraylist and vector Java Collections
What is Vector Java Collections
What are the Java collections Java Collections
Is Hashmap a safe stream collection Java Collections
What is Failfast Java Collections
What is Deque Java Collections
HashTable and Concurrenthashmap - differences and what is more effective Java Collections
What is Bean, what role does Spring play Spring
What is the "Inheritance" OOP
What are the options for Dependensky Injection Spring
What is the difference between Leftjoin, Rightjoin and Innerjoin Databases
What is Dependency Injection in Spring Spring
What is a line in Java Java Core
What is the idea of polymorphism Java Core
Is it possible to override static methods Java Core
How can I implement multiple inheritance in Java Java Core
What methods are located in the interface Java Core
What is the idea of Stream API Java Core
What is Finalize Java Core
What is the relationship of the Equals and Hashcode contract Java Core
The main idea of encapsulation Java Core
Stringbuilder and Stringbuffer, what are the differences Java Core
What is JVM, JDK, Jre Java Core
What is CI/CD General
What types of data exist in Java Java Core
Can a primitive data type to get into HIP Java Core
What is the keyword transient Java Core
What types of testing do you know General
What is String Pool Java Core
What is Spring Boot and what is its main advantage Spring
What kind of Bean Scope do you know Spring
What is the meaning of incapsulation Java Core
What is Springscope Spring
Why is it impossible to compare objects through "==" Java Core
How can you describe an abstraction OOP
Why do you need String Pool Java Core
What is Spring Boot for Spring
How the Try With Resources operator works Java Core
What do you know about the Java 8+ functional interface Java Core
What is Parallel Stream Java Core
What are the foreign keys in the database Databases
What does Garbage Collector work with Java Core

Very Low Occurrence

Question Category
What commands do you use in Git Git
How do you use SOLID principle of openness-covering when designing General
What is the difference between the Builder and Facade design template Patterns
What is the lack of desing patterns Patterns
What are the approaches to organize the development process General
What is the relationship between JS and Java :) General
What are design patterns Patterns
Tell me about your design-patters experience Patterns
What goals do you set for yourself General
What design patterns do you use Patterns
What synchronization channels used to organize the interaction of several services Patterns
What interesting tasks had to be solved General
What is TDD General
What is the easiest way to implement caching General
What types of relationships exist in the structural diagram of classes UML
What are the types of diagrams UML
As if organized the interaction of several services Patterns
What is UML what is a “diagram”, “notation” and “metamodel” in UML UML
What is XSLT XML
What are the pluses of microservices compare to monolith Patterns
What languages do you know that use byte code General
What is JAXP XML
What are the ways of recording XML XML
Tell me something about microservice interaction Patterns
When to use DOM, and when SAX, Stax analyzers XML
What are the XML reading methods, describe the strengths and weaknesses of each method XML
Which structure acts as quickly as possible to the Comand pattern than it can be replaced Patterns
What is the caching for General
What types exist in XSD XML
What is the "namespace" in XML XML
Why do you need a pattern Command Patterns
How the Well-Formed XML differs from Valid XML XML
What is DTD XML
Whether you use the Comand pattern in work Patterns
Caching only works with databases or not General
What is a "deployment descriptor" Servlets
What is XSD scheme XML
How container controls the life cycle of the Serlet, when and what methods are called Servlets
Why do you need application servers if there are server containers Servlets
What is XML XML
What is the advantage of the Builder pattern over the constructor Patterns
What actions need to be done when creating Servlets Servlets
In which case is it required to override the Service () method () Servlets
What is the "Container of the Servmar" Servlets
Which structure acts as quickly as possible to the Comand pattern than it can be replaced Patterns
What is the caching for General
How to implement the launch of the servicema simultaneously with the launch of the application Servlets
When to use the Servetov filters, and when are the listeners Servlets
What types exist in XSD XML
Why are various listener used in the Servlets Servlets
What do you know about the Serpent filters Servlets
What is Servletconfig Servlets
What is ServletContext Servlets
What are the differences of ServletContext and ServletConfig Servlets
Why do I need the Servletresponse interface Servlets
What is the Servletrequest interface for Servlets
What is Request Dispatcher Servlets
How to call another Servable from one sergete Servlets
What is the difference between Sendredirect () from Forward () Servlets
Why are the attributes of the Servita and how working with them is Servlets
What are the differences between GenericServlet and HttpServlet Servlets
Why is httpservlet class declared as an abstract Servlets
What are the main methods in the HTTPSERVlet class Servlets
Which HTTP method is not unchanged Servlets
What are the methods of sending data from the client to the server Servlets
What is the difference between Get and Post methods Servlets
What is the "namespace" in XML XML
Is it possible to use Printwriter and ServletoutPutStream simultaneously Servlets
Why do you need a pattern Command Patterns
What does the URL Encoding mean, how to do it in Java Servlets
What are the most common tasks performed in the server container Servlets
What are cookies Servlets
Why it is necessary to override the only init () method without arguments Servlets
What is the URL REWRITING Servlets
How the Well-Formed XML differs from Valid XML XML
What is a "session" Servlets
Does it make sense to determine the constructor for the servlet, which is better to initialize data Servlets
What is an effective way to make sure that all servus are available only for the user with the right session Servlets
In which case is it required to override the Service () method () Servlets
How to organize a database connection, provide journalization in Services Servlets
What is DTD XML
What authentication methods are available to the sergete Servlets
Whether you use the Comand pattern in work Patterns
Why do you need a jSP Servlets
Caching only works with databases or not General
Tell me about the stages (phases) of the JSP life cycle. Servlets
What actions need to be done when creating Servlets Servlets
What methods of the JSP life cycle can be redefined Servlets
What is a "deployment descriptor" Servlets
What is the difference between the dynamic and static contents of JSP Servlets
What is XSD scheme XML
As a serviceman container controls the life cycle of the Serlet, when and what methods are called Servlets
Why do you need application servers if there are server containers Servlets
What areas of visibility of variables exist in jSP Servlets
What is XML XML
What implicit objects are not available in a regular JSP page Servlets
What is the advantage of the Builder pattern over the constructor Patterns
How to configure initialization parameters for JSP Servlets
What is the "Container of the Servmar" Servlets
What is the structure of the web project Servlets
Tell me about transitivity Frameworks
What are the advantages of the sergete technology over CGI Common Gateway Interface Servlets
What do you use Mavel or Gradeel when assembling the project Frameworks
What patterns used besides Singleton Patterns
Did Java do somewhere else General
What is Lombok General
Tell me about your most interesting project General
Have you heard anything about Spring MVC Spring
What does Dependency Injection give us Spring
What is the difference between IOC and Dependency Injection Spring
What can be returned data types in Spring MVC Spring
What is Swagger for Tools
Where you can use singleton Patterns
Can it turn out so that there is no controller in the context Spring
What we need to make Spring MVC earn Spring
What is Message Broker Tools
What is Scope Spring
What is a context Spring
How Docker differs from a virtual machine Tools
What tasks did the patterns solved Patterns
In what university did you study General
How dependency Injection can be applied to Spring Bean Spring
What is http type Spring
What is the difference between Kubernetes Docker Tools
How Dispatcher Servlet "understands" which method to call Spring
As a client can understand what came to the browser from the server Spring
What is the Dependence Management section for Tools
Why REST is needed Spring
What is the difference between Request Mapping and Put Mapping Spring
What Scope can be used for any application Spring
Request We can use in all Spring applications Spring
Tell me about the structure of the POM file in the Maven packages manager. Tools
Life cycle Maven Tools
How much do you do java General
How do you use Dependency Injection Spring
What IOC implementations do you know Spring
What is Spring IOC container in Spring. Spring
What areas of visibility in Spring you know Spring
What types of implementation of addiction do you know Spring
Tell me what is Inversion of Control Spring
What is Spring Framework Spring
Where it is more convenient to use Java configuration, and where is XML configuration Spring
What is a “performance”, View, and why it is used SQL
What is a “temporary table”, for which it is used SQL
What is Spring IOC container in Spring. Spring
What areas of visibility in Spring you know Spring
What types of implementation of addiction do you know Spring
Tell me what is Inversion of Control Spring
What is Spring Framework Spring
Where it is more convenient to use Java configuration, and where is XML configuration Spring
What is a “performance”, View, and why it is used SQL
What is a “temporary table”, for which it is used SQL
What configuration would be removed Spring
Which of the configuration, XML, Java Annotation, you prefer more Spring
What does NULL mean in SQL SQL
What configuration will be more priority: XML, Java or Annotation Spring
Now in Spring it is not necessary to indicate the AbowireD annotation, why is it so Spring
What are the SQL operators SQL
How to create a controller in Spring Spring
How can you create Servlett in Spring'e Spring
How the context works Spring
Is it possible to create two singleton in Spring. Spring
What is a cursor in a relational database SQL
What are triggers in a relational database SQL
Which prompted to dwell on another programming language General
How you evaluate yourself General
How many contexts can be Spring
What does the SCAN component do Spring
Tell me about the full syntax of Select in a relational database SQL
What is the difference between Filters, Interceptors, and Listeners in Spring Spring
What is the difference between the component and bina Spring
Why is SQL HAVING SQL
What is the difference between Spring Component, Repository and Service Abstracts Spring
What is the life cycle of an object that creates Spring Spring
What Merge does SQL
What is the difference between authentication and authorization Spring
What is JWT for Spring
What is Join SQL
Where did you study General
As if organized the Delete method Spring
How SOAP differs from REST Spring
How to close the connection connection JDBC
How to write a web application on Java Spring
How to cause a stored procedure JDBC
How is the database request and processing the results are carried out JDBC
Why do you need a springs Spring
What are stored procedures and what method of calling through JDBC SQL
With which requests for the database are formed JDBC
What transaction insulation levels are supported in JDBC JDBC
What is the BEAN annotation for Spring
How to register a jdbc driver JDBC
What happens in JVM when starting a program written on Java Java Core
What can tell about the jar file manifesto Java Core
Tell me about the memory areas and Garbage Collector Java Core
Describe the main stages of working with the database using JDBC JDBC
How can you understand that an object is used in memory or not, provided that objects have a cyclic link to each other Java Core
What areas of memory can you remember except stack and heaps Java Core
What are the disadvantages of a pool of lines in terms of security Java Core
What is the difference between RestController from Controller Spring
Is the Poole of the Lines empty at the start of the JAR file or there are some values there Java Core
Due to what LambDA explorations work, which occurs "under the hood" Java Core
You use in the work of lambda expression Java Core
What parts is JDBC from JDBC
How many functionality can be placed in one lambda expression Java Core
Where do Equals and Hashcode methods come from Java Core
Why Hashcode can be equal Java Core
What do you know about the memory models in Java Java Core
When Stream begins its execution Java Core
What is Default Equals and Hashcode modifier Java Core
What is Heap, Stack Java Core
What are the problems during the implementation of hashcode Java Core
What is the eraser of the types for Java Core
From how many classes the class can be inherited Java Core
How to create your own annotation Java Core
Which two classes are not inherited from Object Java Core
What is the grinding of types Java Core
How the parameters are transmitted Java Core
Tell me the features of the Java language Java Core
How Java helps to run the code on operating systems Java Core
How data is stored in Java Java Core
How to determine which object is garbage Java Core
Can developers manage the assembly of garbage and memory parameters Java Core
List the main types of data used in JDBC, how are they related to the types of Java JDBC
What is a class in Java Java Core
What is the class consist of Java Core
How can you compare objects in Java in Java Java Core
What is JDBC url JDBC
What versions of Java worked with Java Core
What are the advantages of using JDBC JDBC
What is the noteworthy Java in the context of the platform Java Core
What is Garbage Collector Java Core
After what moment GC understands that you need to collect garbage Java Core
What GC do you know Java Core
How can we set the GC configuration parameters Java Core
What plugins can be put when creating a virtual machine Java Core
What is the difference between Equals and Hashcode Java Core
Why is it important to override Equals and Hashcode Java Core
In the context of the business, is it necessary to take into account in Equals all the fields of the essence Java Core
Tell me briefly about the idea of processing errors in Java. Java Core
What designs in the processing of errors do you know Java Core
Когда может произойти ситуация, когда мы можем перезатереть исключение Java Core
Where in the processing of exceptions a design with Finally can be used Java Core
What is the value of the byte Java Core
How to quickly make a rest service Spring
What needs to be done in order to override hashcode Java Core
How the line "under the hood" works Java Core
How to bring a line into arrays of characters Java Core
What is ensured by immutable Java Core
What characteristics should the method have a functional ITERPHIS to function Java Core
What needs to be done in order to accept and return values Java Core
Can we without jdk lead java development Java Core
Explain what is due to the fact that int is limited in the amount Java Core
Where reference data types are stored Java Core
Can I use Equals in the form in which it is Java Core
What is the difference between the abstract class and the abstract method, and the abstract method and interface Java Core
What is dynamic polymorphism Java Core
What is the idea of overloading constructors Java Core
Why is immutable so important Java Core
How is the database request and processing the results are carried out JDBC
What is the difference between JVM from JDK Java Core
Do we always need to override Equals Java Core
Why Java platform is independent Java Core
What is the reason for the incomplete Java object Java Core
What is Wrapper class Java Core
Have you heard something about Boxing/Unboxing Java Core
What is the difference between the method and the constructor Java Core
Is it possible to override the method? And the constructor Java Core
What are heterogeneous types Java Core
How to store and process a password working with java Java Core
Where it would be worth applying enum transfers Java Core
What are the most important methods and are used most often Java Core
Whether it was necessary to overlook Equals on their own Java Core
How lines are stored in memory Java Core
What is the problem of concatenation Java Core
Someday I tried the Append method Java Core
What is the difference between Error and Exception Java Core
Give an example of error at JVM level Java Core
What is the problem of verified exceptions Java Core
Would you delete exceptions from Java Checked Java Core
Give examples where CHECKED would use Java Core
Can I make an improved For Each cycle for my object Java Core
What is the most useful method in Object Java Core
What is the advantage of Package Private Java Core
How Package Private can be associated with encapsulation Java Core
Which design template is used for Stringbuilder and Stringbuffer Java Core
Can an array be attached to stream Java Core
What is the coolest method in straps Java Core
What do you know about TargetMethod Java Core
What I heard about Optional class Java Core
Is it necessary to create a class in Java Java Core
Why do you need a springs Spring
What are stored procedures and what method of calling through JDBC SQL
With which requests for the database are formed JDBC
What transaction insulation levels are supported in JDBC JDBC
What is the BEAN annotation for Spring
How to register a jdbc driver JDBC
Describe the main stages of working with the database using JDBC JDBC
What is the difference between RestController from Controller Spring
What parts is JDBC from JDBC
List the main types of data used in JDBC, how are they related to the types of Java JDBC
What is JDBC url JDBC
What is LIST, SET implicitly Java Collections
What are the advantages of using JDBC JDBC
What 3 principles are basic in the OOP Java Core
Where you can apply the polyformity of polymorphism Java Core
Where you can see comprehensive data on primitive types of data in Java Java Core
How to quickly make a rest service Spring
What are reference data types Java Core
That in Java is the most important object for all Java Core
Object classes are inherited clearly or implicitly Java Core
The difference in annotations Service, Repository, Controller Spring
What determines the equivalence of one object to another Java Core
You can characterize what such a state Java Core
Do you know the difference between Stringbuilder and concatenation Java Core
What are restrictions in SQL SQL
Than open fields fraught Java Core
What I heard about the static of typification in Java Java Core
What is the string and features in Java Java Core
Where he was engaged in programming General
What is the Equals method Java Core
What implies immutable Java Core
What is the strict typification in Java expresses itself Java Core
Tell me about JDBCTEMPLATE JDBC
What two main sections of memory for storing data are there Java Core
Have you heard about Stackoverflow Java Core
As it were substantiated that the interface exists Java Core
How can you install a connection with a database JDBC
Which underlies each exception Java Core
How to process exceptions Java Core
As if threw up the exceptions Java Core
What types of proxies do you know Spring
How long lines are stored in String Java Core
Stringpool - part of Heap or something separate Java Core
What is Autocloseable and the Try-With-Rosources design Java Core
What is the difference between Statement and PrepareDstate JDBC
What is the idea in Geneeric generalizations Java Core
Have you heard about new chips of the latest versions of Java Java Core
How to override the Equals method Java Core
What is Resultset JDBC
What is the difference between String and Stringbuilder Java Core
How to create singleton-tin when starting a Spring application Spring
What are the terms of the Equals and Hashcode contract Java Core
What is the difference between Execute, Executequary, Executeupdate JDBC
How Resultset works inside JDBC
Features of the String class Java Core
Do you know what a static class is Java Core
Where he was engaged in programming General
What is a deep copying Java Core
What is the main idea of reflection Java Core
What is Jre Java Core
Tell me about JDBCTEMPLATE JDBC
What terminal operations do we have Java Core
How are the problems of memory deficiency and exclusion of Out of Memory Exception are resolved Java Core
What is Java constructor Java Core
How can you install a connection with a database JDBC
What types of proxies do you know Spring
What is the difference between Statement and PrepareDstate JDBC
What is the main advantage of resources No
What is Resultset JDBC
How to create singleton-tin when starting a Spring application Spring
What is the difference between Execute, Executequary, Executeupdate JDBC
How Resultset works inside JDBC
What projects did you do using Spring Spring
Why do we need Resultset JDBC
What commands do you know from SQL No
Tell me about Execute Executequery and Executeupdate JDBC
Tell the structure of Framework Collection Spring
What is unit testing Testing
What is execution engine JVM
What is Frames JVM
What are the methods of configuration Spring applications Spring
Areas of the time execution time JVM
What is classloader JVM
Where the Bean annotation is used Spring
What is the difference between unit tests and integration Testing
What is JVM for JVM
Describe the general practical principles of working with JSP Servlets
What is the difference between RestController and Controller Spring
What is the difference between JSPWRITER and the Serpent Printwriter Servlets
Why is the Assert Operator used Java Core
Is an object of the session on the JSP page always created, is it possible to turn off its creation Servlets
What is the difference in repository annotations, Component, Controller, Service Spring
What tests do you write and how Testing
How you estimate your level General
Tell me why are you in java General
How to get access to the field of the external class from the invested class Java Core
What is the "local class", what are its features Java Core
What will happen to the garbage collector if the execution of the finalize () method requires significantly a lot of time, or during the execution the exception will be released Java Core
What are "anonymous classes" where they are used Java Core
Is it possible to use JavaScript on a JSP page Servlets
What are the features of the use of nested classes: static and internal, which is the difference between them Java Core
Tell me about the invested classes in what cases they are applied Java Core
How JSP is configured in the deployment descriptor Servlets
Where could Prototype be used Spring
What types of classes are in Java Java Core
Where the initialization of static/non -tatual fields is allowed Java Core
How errors are processed using JSTL Servlets
What is the difference between a member of a class copy and a static class member Java Core
Is it possible to declare the method abstract and static at the same time Java Core
What is Capacy of list Java Collections
By what principle does the number of bakers increase Java Collections
What data structure lies in Arraylist No
How can I process JSP page errors Servlets
What does the Componentscan annotation do No
That during assembly can be provided by Maven No
Against the background of which Spring Date is built No
What is caching No
What is the difficulty of searching for an element in Linkedlist No
What are the types of stitches in JDBC No
What are the requirements for transaction No
Which default Scope is used in Spring Spring
How the vertical and horizontal partners are different No
Are there any contraindications to the use of indexes No
Is it possible to make private variables in the interface No
Will Stream API Randomacess provide No
Is there an iterator in Stream No
What do we use when we write for each No
What is the difference in replication and hearts No
What is the difference between the approaches of Trunk BASD and Feature Branch Git
What is the main problem of the cache No
How to make a stream from the class No
Based on which data structure, Linked List is implemented No
How to access overstroting parental methods Java Core
How to organize a search for Arraylist Java Collections
What is CAS No
What is the difference between PUT and Compute in Map No
Is it possible to narrow the access level/type of the returned value when the method is redistributed Java Core
What does verified and unverified values mean No
How to work on Spring No
What is the difference between JPA and Hibernate No
What is Fetch Type No
What are the mechanisms for complex requests with many parameters No
What is the difference between JDBC species No
What is the difference between atomicity and consistency No
Why you do not need to configure standard JSP tags in Web.xml Servlets
Explain how indexes work No
There is experience with cloud services No
What are we working inside Stream No
What essence in collections helps to access objects in the collection No
What classic functional interfaces you know No
Can non -non -static methods can overload static Java Core
What task the chart solves No
What an exception is released when an error occurs in the class initialization unit Java Core
How to make lines transfer to HTML by JSP Servlets
Tell me about Execute Executequery and Executeupdate JDBC
Is it possible to lose an object in hashmap Java Collections
Tell the structure of Framework Collection Spring
What are Java collections Java Collections
What is unit testing Testing
What are the implementations in the collection of the sheet interface Java Collections
What data structure lies in Arraylist No
By what principle does the number of bakers increase Java Collections
What is execution engine JVM
How the process works if we want to put something in MAP or get Java Collections
What is Capacy Java Collections
How much BUCKET can be in hashmap Java Collections
What is Frames JVM
How to look and delete elements in list Java Collections
What are the methods of configuration Spring applications Spring
How can we bypass the elements of the collection Java Collections
Areas of the time execution time JVM
What is the difference between Hashset and LinkedHashset Java Collections
What is classloader JVM
Whether I heard something about SET Java Collections
Where the Bean annotation is used Spring
What needs to be done to use the Foreach cycle Java Collections
What is the difference between unit tests and integration Testing
What is JVM for JVM
Describe the general practical principles of working with JSP Servlets
Can it be that in Hashmap there will be two identical keys Java Collections
What is the difference between RestController and Controller Spring
What restriction is to add to Treeset Java Collections
What are "anonymous classes" where they are used Java Core
Can Treeset store null Java Collections
What is the difference between JSPWRITER and the Printwriter Servlets
What are the main implementations about the collection Java Collections
What will happen to the garbage collector if the execution of the finalize () method requires significantly a lot of time, or during the execution the exception will be released Java Core
What is the level of complexity in Hashset when looking for an element Java Collections
Why is the Assert Operator used Java Core
How structurally a two -link list looks compared to the single Java Collections
Is an object of the session on the JSP page always created, is it possible to turn off its creation Servlets
What will be the speed of access to the element in LinkedList, which is located in the middle Java Collections
What is the difference in repository annotations, Component, Controller, Service Spring
What tests do you write and how Testing
How you estimate your level General
What will be the search speed in linkedlist Java Collections
Tell me why are you in java General
What is the search speed in Arraylist Java Collections
How to get access to the field of the external class from the invested class Java Core
What is the speed of access to the element in Linkedlist by index Java Collections
What is the "local class", what are its features Java Core
Is it possible to use JavaScript on a JSP page Servlets
What are the features of the use of nested classes: static and internal, which is the difference between them Java Core
What to have inside Hashset and Treeset Java Collections
Tell me about the invested classes in what cases they are applied Java Core
LinkedList single -legged or two -link Java Collections
How JSP is configured in the deployment descriptor Servlets
Tell me about LinkedHashmap Java Collections
Where could Prototype be used Spring
What types of classes are in Java Java Core
Where the initialization of static/non-static fields is allowed Java Core
How errors are processed using JSTL Servlets
What is the difference between a member of a class copy and a static class member Java Core
Is it possible to declare the method abstract and static at the same time Java Core
How can I process JSP page errors Servlets
Have you heard something about the Foreach cycle Java 8
Which default Scope is used in Spring Spring
What mechanism is used in the implementation of parallel streams Java 8
What is the difference between the approaches of Trunk BASD and Feature Branch Git
What is a link to the method and how it is realized Java 8
How to access overstroting parental methods Java Core
Is it possible to override the access level/type of the returned value when the method is private Java Core
Why you do not need to configure standard JSP tags in Web.xml Servlets
What is Dirty Checking in Hibernate Hibernate
Can non -non -static methods can overload static Java Core
What an exception is released when an error occurs in the class initialization unit Java Core
How to make lines transfer to HTML by JSP Servlets
What is serialization Serialization
Where and when used Prototype Spring
What is http protocol WEB
What will happen if an exception throws in the constuctor Java Core
Why Java uses static initialization blocks Java Core
Give an example of using your own tags Servlets
What designs Java are applicable to the Static modifier Java Core
What is the procedure for calling constructors and blocks of initialization taking into account the hierarchy of classes Java Core
What do you know about writing user jSP tags Servlets
What will happen if in ApplicationContext you try to get the same bin Spring
How to drain two different branches Git
What position I would like to claim General
Can an object gain access to a Private-cross-class class, if, yes, then how Java Core
That has a higher level of abstraction - class, abstract class or interface Java Core
How can JSP functionality expand Servlets
Why is it impossible to declare the interface method with the Final modifier Java Core
Why in some interfaces do not determine the methods at all Java Core
What groups of tags do the JSTL library consist of Servlets
In what cases should the abstract class should be used, and in which interface Java Core
What modifiers by default have fields and interfaces methods Java Core
Why do you need a program that works in several threads, and not in one Multithreading
What is JSTL, JSP Standard Tag Library Servlets
What are the options for synchronization in Java Multithreading
What is Atomic Types, what are they needed Multithreading
What is the security of the threads Multithreading
What is the meaning of the keyword of Volatile and related problems Multithreading
Where and for what the ABSTRACT modifier is used Java Core
How to adjust the thread priority and how Multithreading
What is the object of the interface Runnable Multithreading
What groups of tags do the JSTL library consist of Servlets
What is the semaphore Multithreading
What does Wait method do Multithreading
What is a stream of "demon" Multithreading
What is the meaning of Readwritelock Multithreading
In what cases should the abstract class should be used, and in which interface Java Core
What modifiers by default have fields and interfaces methods Java Core
What is JSTL, JSP Standard Tag Library Servlets
Where and for what the ABSTRACT modifier is used Java Core
What beaten operations do you know Java Core
Dike the implicit, internal objects of JSP EL and their differences from JSP objects Servlets
What are the general branching strategies you know Git
What is a thornsary choice operator Java Core
What logical operations and operators know Java Core
What types of EL operators know Servlets
What do you know about the function of Main () Java Core
What values are initialized by default variables Java Core
What do you know about the language of JSP, JSP Expression Language - EL Servlets
What are the exceptions Java Core
What is and how the cloning of objects, arrays and two -dimensional arrays is used Java Core
What is autoboxing Java Core
What is an initialization block Java Core
Is it possible to determine the class inside the JSP page Servlets
What are the disadvantages in the index Databases
What is primary and external keys and what restrictions exist Databases
What is DANEAL DENORMALISE Databases
What is the idea of Foreign Key Databases
What is the difference between JPQL and HQL Databases
What is a relational data model Databases
What arises that anomalies arise when performing parallel transactions Databases
What is database replication Databases
How I kept data in projects Databases
As it were to send a message to the client, given the possibility of canceling the transaction Databases
How to avoid the fact that the data package can go twice Databases
What databases did you use Databases
What are the restrictions on the keys Databases
Where I used the annotation Transactional Databases
Why is the database better than a text file Databases
What is indexing Databases
What types of requests do you know Databases
Have you heard something about DML and DDL Databases
Name a brief list of three restrictions Databases
What is the meaning of the second normal shape Databases
Describe the shape of the code Databases
That we most often use in aggregation in aggregation requests Databases
What is performed before Were or Join Databases
How can you add restrictions Databases
With which we can specify constraint Databases
What are Venna diagrams Databases
How to add restrictions to the database Databases
What is Join's idea Databases
What I heard about the Exists operator Databases
Tell the interruption and second form of normalization Databases
What is a constructor for copying No
What is the idea of Builder No
What is unique applied to No
Why is it not recommended to use science, script elements, in jSP Servlets
Can there be a situation where Primary Key is repeated No
What is the basis of Spring Framework No
Is it possible to introduce dependence not only through the constructor No
What is performed earlier: constructor, setter or implementation field No
File specimen contains only a file path No
What do the relationship "is" and "have" in the OOP No
Where it is better to use inheritance and association No
Why are you needed versions control systems? Git
Why do you need Final for a static method No
Why Throws is bad in the signature of the method No
How to throw exceptions correctly No
Tell me about how you understand the principles of Solid based on your experience General
Tell me about File class and its device No
How to avoid compulsory IOEXCEPTION processing No
What is atomic and consistency No
Why is Java Memory Model important when working with multi -thread No
What is the difference between Synchronized and Lock No
What is callable No
Advantages of the implementation of Executorservice No
Why Hashmap appeared No
Why is it bad to make an array of bytes for hashmap No
What is HashTable problem No
What is automatic increment in different databases No
What are the insulation levels in SQL No
Tell me about the idea of Framwar Hibernate No
What types of communication in Hibernate are there No
What annotations are there to create bins No
What is the value of the Bean annotation No
What is BeandEfinition and why is it needed No
How to contact another service from a Spring application No
What is the value of Spring Boot No
What starters do you know in Spring Boot No
Is it necessary to catch Throws No
What is encapsulation for No
Stack, is it a long -term storage No
How can you compare with each other data types No
As primitive data types can be compared to each other No
Whether I heard something about static methods No
Why Equals need to be redistributed and why No
What are the main implementations of leaf collections No
What is your total experience in Java General
What is the advantage of Hibernate over JBC No
What is caching in Hibernate No
There is experience in writing tests No
Familiar with the principles of system scaling No
What is a dock No
What he worked with from the point of view of security No
How many parts is JVTTOKEN No
What is the feature of Spring Boot No
What types of tests do you know No
What contains the task that came from analysts No
What is Main method No
What gives the word static No
Why Main is considered static No
What are arrays in Java No
What class is realized by the dynamic array in Java No
Due to which NIO provides non -insoluble access to resources No
What is the feature of CopyonWritearraylist No
What is Stream in the Stream API context No
What is EXECUTORSERVICE for execution No
What is meant by the letter O in Solid No
What are the differences between the strategy pattern and state pattern No
What is an adapter No
What is a group in the database No
What are the main orm realization in Java No
What levels of caching are there in hibernate No
What is Docker No
What is the difference between a docker and a virtual machine No
How is JVM memory arranged No
What are stacks No
How the data between the glass and the hit pass No
What is garbage assembly No
What is multi -fluidity, parallelism and asynchronism No
What are Future and Completablefuture classes for No
What is under the letter L in the principles of Solid No
What is Result Set in JDBC No
Features of Result Set in JDBC and its configuration No
What is SessionFactory in Hibernate No
Tell me about the control levels of transaction insulation in Hibernate No
What is in the Collections Hiorarchies API No
TREMAP class, which data rod underly No
What is the complexity of the binary search No
Why do you need Future No
Why do you need Completablefuture No
JDBC is the implementation or specification No
Why load a database driver No
What is Statement No
What types of statement are there No
What is JPA No
What is n+1 select problem No
Final use options No
What is the ITERABLE interface No
What is REST API No
What is the difference between a functional approach and object-oriented No
What is the transmission of parameters in Java and how it happens No
What principle of OOP does the reduction of the methods belong No
What are Immutable objects No
With what functional interface do we work in the MAP () method No
What is Named Query in Hibernate No
What is BeanpostProcessor No
What is Bean Scope No
What types of scope exist No
What does the framework Spring do No
What is oc and di No
What is the difference between an ordinary object from Bean No
What is Maven No
Why do we use access modifiers No
Is it the correct statement that the String massif is the Char No
What are the key classes Exception No
How can you process exceptions No
What is a phantom reading No
What does Fetchtype Lazy mean No
What entities are involved in creating Bean No
What is asynchronism No
What are the advantages of the composition in the OOP No
What can lead to a violation of the principles of Solid No
What are the immobilization of the LIST interface No
When to use LinkedList No
What determines the range of permissible values of "primitives" No
What does Peek () method do No
How CAS mechanism works No
Which gives the principle of incapsulation in real systems No
Tell me about the third normal shape No
What is the main task of caching in ORM No
What difficulties can arise when working with caching No
What problem does Framework Spring solve No
NAVOV DIFFERENT OF OOP and functional programming No
What is a composition No
What are the advantages of the composition No
As you understand Interface Segregation No
What is Dependency Inversion No
What is the covarian of types No
How can you make a class unchanged No
What is the difficulty of searching for a key method in the Treemap collection No
What does Peek method do in Streamapi No
What interface we get in the Foreach () method No
Where static methods are stored in JVM memory No
How to optimize the work of Hibernate No
How to perfectly organize the CI/CD process No
Why is multiple inheritance prohibited No
When Hashcode conflict in Hashmap occurs No
What is a functional paradigm No
What is in the center of the paradigm No
What is callable No
What is the meaning of multi -seating No
What can lead to a violation of normalization No
How are bins initialized in Spring No
What does Transactional annotation in Spring Data do No
What is CAS mechanism No
What is the difference between Optimistic and Pessimistic Lock in Hibernate No
What streamline collections in Java know No
What is LinkedHashmap. No
What lies "under the hood" Parallelstream () No
Tell me about the methods of optimizing requests in the database No
What is the algorithmic complexity of searching for an element by index No
What is Join differ from Union No
Tell me about Problem N+1 in Hibernate No
What is ApplicationContext in Spring No
As if implemented integration testing No
Where static methods and variables are stored No
Where objects are stored No
What is "garbage" in terms of JVM No
What is CAS mechanism No
What groups of teams are there in SQL No
What are transaction insulation levels No
How to process the request (httpservlet) No
What is the difference between the composition and inheritance No
Mechanisms for the implementation of polymorphism No
What are unchanged classes No
What is the difficulty of inserting the element in Linkedlist No
What is the difference between the volatility and atomicity No
N+1 Problem, solutions in Hibernate No
What are transactions promotion levels in Spring Data No
What is a hypothetic method in Spring Data No
What is CAP theorem No
How the object differs from primitive No
What algorithms for finding an element by array are known No
Tell me about the concept of the Completablefuture class No
Why can the design template be useful to a chain of responsibility No
Bean is a class or object No
What are propagation levels in transactions No
What is the ideality of the method No
What is the ideality of the method No
Tell about yourself what goals you set No
What is the permissible range for the type of SHORT data No
What is the difference between a primitive Short from Class Short No
How Java understands Generics No
What idea does Arraylist realize No
What does transient in Java mean No
What does transient in Java mean No
What idea does LinkedList realize No
What is the difficulty of inserting the element in Linkedlist No
What is the Comparable interface for No
What can lead to a violation of data normalization No
What can you reconcile Final No
What is LinkedHashset No
What is Hashset No
What Phaser does No
What are scope bean for No
What is Socket No
Why is the strategy template is used No
I studied something except Java No
As you understand the phrase java is OOP No
Array is a primitive or object No
What is the difficulty of adding an element to Array List No
Which you know the most effective way to copy the array No
What is a collision of a hash codes from the point of view of Hashmap No
What problem does Walatayl solve No
What tasks are solved using Join No
How to make a database with Java application No
What is the name of the document in which I can see everything about JDBC No
What types of queries can I perform using hibernate No
For complex requests where there are a lot of paraments that you need to use No
What happens from the start of the Spring of the application to the first request to Postman No
What is the difference between Hashmap and Hashset No
What is Spring Data Repository No
What is Spring Data Specification No
What are the differences in component annotations No
What is the difference between the configuration and the component No
What is @transactional annotation No
What will happen if the method is caused by the @transactional annotation method No
What is the difference @Controller and @readController No
How to effectively identify unproductive SQL - requests No
How to deal with anomalies when performing transactions No
What is Message Broker No
What is asynchronous messages No
What are non -blocking algorithms No
What is the difference between Mono and Flux No
What will happen if you apply Volatile in objects No
How to ensure synchronization in a multi -thread environment No
What is the Synchronized block in Java and what are the problems are there No
What is the Database-Per-Service template No
What is the EVEN Sourcing template No
What tasks does Distributed Tracing solve No
How to choose a strategy, template No
How will Prototype Bean behave in the framework of Singleton No
What you use as tracking your tasks No
What FLO do you use when working with TASK No
Tell me the difference between the List and Set interface No
What is an executter-service No
That with the exception of Interrupted Exception No
What annotations you know to create bins No
What is the promotion and bias of the transaction No
Briefly tell me about your projects No
Why inheritance is needed No
What alternatives are there inheritance No
Why the composition is more often recommended to use than inheritance No
What is the main idea of the adapter No
What is the idea of Autoboxing and Unboxing No
What needs to be done in order to create a property class in Java No
The basic differences between List and Linked List No
What methods of processing are checked exceptions No
What is Try/Catch No
Is it possible to write try without Catch No
What forms of writing Try/Catch know No
What is the importance of Stack Trace in exceptions No
What is understood by the context of error No
What is constistence and chieftain No
Is it possible to manage a monitor No
What is a steameterized type No
Is there a constructor for a static class No
How to create a static generical method No
What does Java mean two types of exceptions No
What methods of processing in Java exist No
Why is it necessary to close the resource No
Is it possible to launch a Java application with only jre No
What is ODBC No
What does a static in Java mean No
What is the difference between Exception and Error No
Data transmission to Java is following the link or by value No
What does the transmission mean by No
Why do I need property classes and their main characteristics No
What is the insulation or its absence No
Is it possible to lower the level of access modifier No
What are the main three methods for Servlet and what is their task No
How Servlet works in multi -sided mode No
Arraylist, what is the speed of access to the last element No
What is the difference between PrepareDstatement and Statement No
What is the relationship in the database No
What is One to One No
Give an example One to Many No
What two main types of data integrity do you know No
What types of constraints do you know No
What is DDL, DML, DCL No
How to fight the database from SQL Injection No
What is the difference between Union and Union All No
What are the main restrictions when working with Union operation No
What is comit in SQL No
What problem can the transaction set No
What is the principle of abstraction No
What is the difference between abstraction and polymorphism No
What is the difference between Race Condition and Data Race No
What methods of synchronization in Java do you know No
What is the difference between Dependency Injection and Dependency Inversion No
What is Dispatchers Roulette No
What is the difference between inheritance and polymorphism No
What is contract programming No
Why is it so important to have a contract in Java No
What are the main two types of Singletone implementation No
What is a decorator No
What is the decorator for No
What does reflection mean No
What does symmetry mean No
Why do objects fall into Stringpoll No
How objects fall into StringPoll No
What is the problem of concatenation of lines in Java No
How Stringbuilder solves the problem of concatenation No
Are Stringbuilder faster than Stringbuffer if you remove synchronization No
What is the reason for the existence of MAP as a data structure and Collection in CollectionFramework No
What is the main vocation of the MAP interface No
What are the basic implementations of InputoutPut Strem No
What is the minimum unit for working with threads No
What is the progressiveness of NIO No
What is the meaning of buffering threads No
What is the advantage of buffering No
What is the advantage of buffering No
How Track.h works No
What will happen if we try to change the value of a private variable No
What is the difference in aspects between Advice and Point No
What is the difference in aspects between Advice and Point No
Why logging is very often associated with aspects No
Give an example of a relational database and a non No
What is the meaning of restrictions No
What are the restrictions No
How is the access speed in SQL achieved No
Primary Key is an index and why No
What restrictions do Primarykey have No
What is Asset principle No
What negative phenomena in SQL know No
What is meant by Dirtyread No
What types of configurations do you know No
Why is it necessary to use the configuration through annotations, and you should not use the aanotation through the configuration No
In what cases would Java use configuration No
What annotations you know for the message of Spring, so that it creates on the basis of these Bean annotations No
What is the feature of Dependency Injection No
What is Spring Data No
What is the difference between Spring Data from Hibernate No
How to fill the attributes in the class No
What is JSON data storage format No
What is characteristic of html No
What is SELECT from SQL No
How to make your first commit, add all files No
How can you make a connection with a remote repository No
How to download changes from a remote repository No
What is Spring No
What does the Spring Core module give No
Try Catch with Resources what is it No
What is Git for No
What kind of Git commands do you know No
What is MAP No
Can a primitive key be No
Map keys can be repeated No
What are the data structures from Collection No
What is SET No
What is List No
What is the difference between List and SET No
What is Q and DQ No
Does LinkedList have Q/DQ interfaces No
What is a temporary complexity No
What are Exception classes, what types of No
What is the EXCEPTION inherited No
Why are Stream needed No
Stream API What paradigm uses No
What are the types of Stream No
Can a private method be in the interface No
What is the name of the functional interface that accepts the filter No
What Collect does No
Is it possible to transform the collection into MAP No
Can there be a constructor in the interface No
Overloading the method what it means No
What is a signature No
There is String, String Builder, String Buffer what is it No
What is the living cycle Maven No
What is an oc container No
What do you know about the annotation Predestroy No
What gives an annotation of Service No
What is Spring Web No
What is Mock, Stab, Spy No
How to connect a class with a database No
Lazy vs eager loading, what is the difference No
Why did the division of data types into Int, Long No
What is the idea of primitive data types No
What are programming patterns for No
What is a container No
What is the introduction of dependence No
What is the difference between Spring Boot and Spring Context No
Which annotation allows you to understand that bins are raising No
How to connect your library in another project No
What should be the conditions for the database to be considered a relational No
How to prohibit leaving an empty column No
Why do you need branches in Git No
How to see the version of the previous commune No
What are the types of branches of branches No
How to find a mistake in the program No
How can you test the program and protect yourself from errors No
What types of cycles do you know No
How the cycles differ from each other No
Tell me briefly with which frameworks you worked No
Which from the literature on Java read No
What literature I read not according to Java No
Did Java.util.concords use Java 5 No
What in recent times I learned or read that you can advise No
Tell me briefly what you did in programming No
Tell me about your experience of translating the project to Java No
What to do if there is no Right Join in the database, but there is Left Join No
What is BDD General
What are the merger strategies from the point of view of the database developer No
As if implemented a table in a database for 100 million records, with a search on the Int32 column No
How to make a quick search without sorting an integration of millions of values No
What do you think about the test type of exceptions in Java No
If I developed a library for working with http, I would use exceptions or something else No
Why are the pools of connections in the database are needed No
How the Close method works when working with the connection pulle to the database No
Used Kotlin No
What would I want to remove from Java No
Whether it was spent with Content No
Did you do any projects with many streams No
What types of variables are in Java No
What Java elements are responsible for inheritance No
What is a reduction in the method No
What is the class Pojo No
How JPA differs from Hibernate No
Can the entity class be abstract No
What is Exception No
Tell me about your success in programming No
How can you optimize a highly loaded web service No
What tools used in addition to Java No
What is Branch in Git No
How to check that your program works correctly No
We have a web service and in logs it is written "Record Not Found" - how to understand No
The user came and says that the data is not displayed, your actions No
Need the "Delete Report from the System" button, your actions No
What is the distance between the moon and the Earth No
What are the principles of programming that help write a beautiful code you know No
Tell me about the SEGREGATION interface No
What are http methods No
What are the HTTP queries methods No
What is the difference between http requests No
What is strong and weakness in the understanding of the code No
What is atomic types and why they are needed No
What are interfaces-markers and why they are not created now No
What evolutionary development has received interfaces-markers and what replaced them No
For what purpose is serialization applied No
What is PECS principle and how it is used No
Why can Immutable objects need in practice No
What is error processing No
What to do if Error flew out, can we catch it and somehow process it No
It is known that when the method A is called, the exception will be issued, your actions No
How to get a Cant Convert Modification Exception when working with a collection No
Streams, what operations and types of operations are there No
What functional interfaces do you know No
What is the difference between Default Methods from Static Methods No
What are the types of databases No
What are the advantages and disadvantages of database types No
What is the normalization of data in a relational database No
Tell me about the syntax of the creation of the table in a relational database No
How to change the table in a relational database No
You know what a request plan is in a relational database No
How Spring "under the hood" works No
Why do you need Hibernate No
That it is better to use Join or subclasses SQL
What is the ORDER BY operator used for SQL
How Group by processes Null value SQL
List the main aggregate functions SQL
What is the difference between Count (*) and Count ({column}) SQL
What is operators: in, Between, Like SQL
When the keyword UNION is used SQL
What are the differences between Primary and Unique restrictions SQL
Is the value in the column, which is imposed on the restriction of Foreign Key, is NULL SQL
How to create an index SQL
What is the difference between Delete and Truncate operators SQL
Describe the difference between DATETIME and TIMESTAMP data SQL
What is the purpose of Pivot and Unpivot operators in Transact-SQL SQL
Tell me about the main functions of ranking in Transact-SQL SQL
Why are Intersect operators used, Except in Transact-SQL SQL
What are "anonymous classes" where they are used Java Core
What is denormalization for Databases
Criteria API Databases
What is HQL Databases
Is it true that primitive data types are always stored in the stack, and specimens of reference data types in a heap Java Core
Tell me about the type of type, what is a decrease and increase in type Java Core
Когда в приложении может быть выброшено исключение ClassCastException Java Core
What are literals Java Core
Why string is an unchanged and finalized class Java Core
Why Char [] is preferable to string for storing password Java Core
Why a line is a popular key in Hashmap in Java Java Core
Is it possible to use lines in the design of Switch Java Core
Why is the Clone () method announced in the Object class, and not in the Cloneable interface Java Core
What is the "default constructor" Java Core
How the constructors differ by defending, copying and constructor with parameters Java Core
Where and how you can use a closed constructor Java Core
Tell me about the classes-loaders and about dynamic class loading Java Core
Equals () gives rise to the ratio of equivalence, what properties does this attitude have Java Core
How are Hashcode () and Equals () methods in class Objecte implemented Java Core
Are there any recommendations about which fields should be used when counting Hashcode () Java Core
Which operator allows you to force the exception Java Core
What is the keyword of Throws talking about Java Core
How to write your own ("user") exception Java Core
What are the Unchered Exception Java Core
What is Error Java Core
Can one Catch block catch several exceptions at once Java Core
Is Finally a block always executed Java Core
Are there any situations when the Finally block is not completed Java Core
Can the Main method throw out the exclusion outside and if so, then where the processing of this exception will occur Java Core
What is "Internationalization" Java Core
What is "localization" Java Core
Differences of Softreference from Weakreference Java Core
How to write immutable grade Java Core
Intermediate operations in Stream API Java Core
The life cycle of the Servtov Java Core
What is Default Method on Interface Java Core
Using the InstanceOF operator Java Core
Is adding always to ArrayList the complexity O (1) Java Core
Did generics always exist in Java Java Core
What is WildCarts Java Core
What are the main JCF interfaces and their implementation Java Collections
What is the difference between Java.util.collection and Java.util.collections classes Java Collections
Give examples of iterators realizing Fail-Safe behavior Java Collections
How the enumeration and iterator differ Java Collections
How it is the itrable and iterator Java Collections
How it is interconnected by iterable, iterator and “for-each” Java Collections
Compare Iterator and Listiterator. Java Collections
What will happen when iterator.next () call it without preliminary call iterator.hasnext () Java Collections
How the collection behaves if it call iterator.remove () Java Collections
How the already instituteed iterator will behave for Collection, if you call collection.remove () Java Collections
How to avoid ConcurrentModificationException during the enforcement of the collection Java Collections
Which collection implements FIFO service discipline Java Collections
Which collection implements the discipline of Filo service Java Collections
Why added ArrayList if there was already Vector Java Collections
That works faster than Arraylist or LinkedList Java Collections
What the worst time of the Contains () method for the element that is in LinkedList Java Collections
What is the worst time of the Contains () method for the element that is in Arraylist Java Collections
What the worst time of the Add () method for linkedlist Java Collections
What the worst time of the Add () method for Arraylist Java Collections
How is the removal of elements from Arraylist, how in this case the size of Arraylist changes in this case Java Collections
Offer an effective algorithm for removing several nearby elements from the middle of the list implemented by Arraylist Java Collections
How much additional memory is needed when calling Arraylist.add () Java Collections
How much is the addition of memory when calling linkedlist.add () Java Collections
Assess the number of memory for storage of one BYTE type primitive in LinkedList Java Collections
Assess the number of memory for storage of one BYTE type primitive in Arraylist Java Collections
Compare the interfaces Queue and Deque Java Collections
Who expands whom: Queue expands Deque, or Deque expands Queue Java Collections
Why is LinkedList implement both List and Deque Java Collections
How to sort out LinkedList elements in the reverse order without using a slow get (index) Java Collections
Which allows you to make priorityqueue Java Collections
Stack is considered "outdated", which is recommended to replace it, why Java Collections
What is Identityhashmap for Java Collections
What is the difference between Hashmap and IdentityHamap Java Collections
Why is Weakhashmap used Java Collections
What is the difference between Hashmap and Weakhashmap Java Collections
What is the “sorting” of SortedMap, in addition to the fact that tostring () displays all elements in order Java Collections
What is the assessment of temporary complexity of operations on elements from Hashmap, whether Hashmap guarantees the specified complexity of the sample of the element Java Collections
Is the situation when Hashmap degenerates into the list even with keys having different hashcode () Java Collections
Why you can not use byte [] as a key in hashmap Java Collections
What the worst time of the Get (Key) method for the key, which is not in hashmap Java Collections
What the worst time of the Get (Key) method for the key that is in Hashmap Java Collections
How many transitions are at the time of calling Hashmap.get (Key) on the key that is in the table Java Collections
How many new objects are created when you add a new element to hashmap Java Collections
How and when there is an increase in the number of baskets in hashmap Java Collections
Explain the meaning of the parameters in the constructor Hashmap (Intialcapacy, Float LoadFactor) Java Collections
Will Hashmap work if all added keys will have the same Hashcode () Java Collections
How to sort all the keys Map Java Collections
How to sort out all MAP values Java Collections
How to sort through all pairs of "key-meaning" in MAP Java Collections
What will happen if you add elements to Treeset by increasing Java Collections
For Enum there is a special class Java.util.enumset, why, why the authors did not suit Hashset or Treeset Java Collections
What are the ways to sort out the list elements Java Collections
How can synchronized objects of standard collections be obtained Java Collections
How to get a collection only for reading Java Collections
How to copy the elements of any Collection in an array with one line Java Collections
How to convert Hashset to Arraylist one line with one line Java Collections
How to convert Arraylist into Hashset one line with one line Java Collections
Collections.emptylist () or new copy Java Collections
Whether Hashmap guarantees the specified complexity of the element sample Java Collections
What is the maximum number of hashcode () values Java Collections
What are the main SET implementation Java Collections
What are the main implementation of MAP Java Collections
Copyonwrite collection Java Collections
How to get an endless cycle using hashmap Java Collections
Why MAP is not inherited from Collection Java Collections
Why you can not use byte [] as a key in hashmap Java Collections
What tree lies in the implementation of Treeset Java Collections
Why there are no specific implementations of the Iterator interface Java Collections
What innovations appeared in Java 8 and JDK 8 Java 8
What variables have access to lambda-expression Java 8
How to sort the list of lines using lambda expression Java 8
What types of links to methods do you know Java 8
Explain the expression system.out :: println Java 8
Why are the functional interfaces of Function <T, R>, DOUBLEFUNCTION <L>, IntFUNCTION <L>, LONGFUNCTION <R> Java 8
Why are the functional interfaces of Binaryoparator <t>, DoubleBinaryoprator, Intbinaryoprator, Longbinaryoprator Java 8
Why are the functional interfaces Predicate <t>, DoublePredicate, IntPredicate, Longpredicate Java 8
Why are the functional interfaces of consumer <t>, DoubleConsumer, Intconsumer, Longconsumer Java 8
Why do you need a functional interface biconsumer <t ,u> Java 8
Why do you need a functional interface bifunction <t, u, r> Java 8
Why do you need a functional interface bipredicate <t ,u> Java 8
Why are functional interfaces of the type _to_FUNCTION Java 8
Why are the functional interfaces of TODOBLEBIFUNCTION <T, U>, tointBifunction <T, U>, Tolongbifunction <T, U> Java 8
What are the functional interfaces of TODOBLEFUNCTION <T>, tointFUNction <T>, TOLONGFUNCTION <T> ` Java 8
What are the functional interfaces of Objdobleconsumer <t>, objintconsumer <t>, objlongconsumer <t> ` Java 8
What is Stringjoiner Java 8
How to call the Default interface method in the class implementing this interface Java 8
What is a Static interface method Java 8
How to call a static interface method Java 8
What are the ways to create stream Java 8
What is the difference between Collection and Stream Java 8
What is the Collect () method in straps for Java 8
Why are the MAP () and Maptoint (), MaptodOble (), Maptolong () are intended in streams. Java 8
Why in straps the LIMIT () method is intended Java 8
Why is the Sorted () method intended in streams Java 8
Why are the Flatmap (), Flatmaptoint (), FlatmaptodOble (), Flatmaptolong () methods for straps are intended for streams. Java 8
What final methods of working with streams do you know Java 8
What intermediate methods of working with streams do you know Java 8
What additional methods for working with associative arrays (Maps) appeared in Java 8 Java 8
What is LocalDetetime Java 8
What is ZoneDDATETEME Java 8
What is NASHORN Java 8
What is JJS Java 8
What class appeared in Java 8 for coding/decoding data Java 8
What are the main characteristics of the templates Patterns
Types of design templates Patterns
Give examples of the main design templates Patterns
Give examples of generating design templates Patterns
Give examples of structural design templates Patterns
Give examples of behavioral design templates Patterns
What is "antipatttern", what antipatterns you know Patterns
What is "integration testing" Testing
What are the types of test objects Testing
How Stub differs from Mock Testing
What are "fixed" Testing
What are the annotations of fixes in Junit Testing
Why junit uses @ignore annotation Testing
How to change the standard behavior of serialization/deserization Serialization
How to exclude fields from serialization Serialization
What influence do Static and Final field modifiers have on serialization Serialization
How to prevent serialization Serialization
How to create your own serialization protocol Serialization
What is the role of the Serialversionuid field in serialization Serialization
When it is worth changing the value of the Seerialversionuid field Serialization
What is the problem of Singleton serialization Serialization
What are the methods of monitoring the values of the deserialized object Serialization
What features of NIO do you know Streams
What are "channels" Streams
What are the types of input/output streams Streams
What are the main classes of input/output streams Streams
In which packages are the classes of input/output streams Streams
What kind of Inputstream class subclasses do you know why they are intended Streams
What is PushBackinputstream used for Streams
Why is Sequenceinputstream used Streams
Which class allows you to read data from the input byte stream in the format of primitive data types Streams
What subclasses of the Outputstream class know what they are for Streams
What are the Reader class subclasses what they are for Streams
What kind of Writer class subclasses do you know why they are intended Streams
What is the difference between Printwriter class from Printstream Streams
What is different and what in common has Inputstream, outputstream, Reader, Writer Streams
What classes allow you to convert bytic stream into symbolic and vice versa Streams
What classes allow you to accelerate reading/recording through the use of the buffer Streams
Pattern observer General
Which class is designed to work with the elements of the file system Streams
What are the File class methods Streams
What do you know about the FileFilter interface Streams
What do you know about Randomaccessfile Streams
What kind of access to the file does Randomaccessfile have Streams
Which classes support reading and recording stream in a compressed format Streams
Is it possible to redirect the stream of standard input/output Streams
What is the symbol by a separator when specifying a path in the file system Streams
What is the "absolute path" and "relative path" Streams
What is a "symbolic link" Streams
What is www WEB
What is W3C WEB
What are OSI model levels WEB
What is TCP/IP WEB
What is UDP WEB
What is the difference between TCP and UDP WEB
What is a data transfer protocol WEB
What data transmission protocols do you know WEB
What is FTP WEB
What is MIME type WEB
What is Web Server WEB
What is Web Application WEB
What is Application Server WEB
What is the difference between Web Server and Application Server WEB
What is Ajax, how this technology is fundamentally arranged WEB
What is WebSocket WEB
What is json scheme WEB
What is "HTML" WEB
What is "HTML" HTML
What is "XHTML" HTML
What is doctype and why it is needed HTML
What is the <head> tag is intended for HTML
What is the difference between <div> from <span> HTML
How are comments in HTML HTML
How is the address of the document to go to HTML
How to make a link to the email address HTML
Why is the tag <em> HTML
Why are the tags <ol>, <ul>, <li> are intended for HTML
Why are the tags <dl>, <dt>, <dd> HTML
Why are the tags <tr>, <TH>, <td> are designed HTML
Is it necessary to write an ALT attribute in the <img> tag HTML
In which register is it better to write a html code HTML
What is "Mnemonics (Entity)" HTML
What is CSS CSS
How CSS contains comments CSS
What is a "selector" CSS
List the main types of selectors CSS
What is Psevdoklass CSS
What are the attribute selectors CSS
What is the difference between #MY and .MY CSS
What is the difference between Margin and Padding CSS
What is the difference between the values of 0 and Auto in the margin property CSS
What property does the background color set CSS
What is the property of Clear for CSS
What is a "messaging" OOP
Tell me about the interface OOP
What implies in terms of the principles of OOP expression "is" and "has" OOP
What is the difference between composition and aggregation OOP
What languages are on JVM General
What is reactive programming General
What is DDD General
What is FDD General
CI/CD tools General
Memory leak General
Memory leaks in java General
The complexity of fast sorting General
What is Big O General
What is a lazy load General
What is the difference between "competition" and "parallelism" Multithreading
What is "cooperative multitasking" Multithreading
What type of multitasking is Java uses, what is the condition of this choice Multithreading
What is ORDERING Multithreading
What is AS-IF-SERIAL SEMANTICS Multithreading
What is Sequential Consistency Multithreading
What is Visibleity Multithreading
What is atomicity Multithreading
What is Mutual Exclusion Multithreading
What is Safe Publication Multithreading
What are "green threads" and whether they are in Java Multithreading
What is the difference between the Start () and Run () methods Multithreading
How to start a stream forcibly Multithreading
In what states can a stream be Multithreading
Is it possible to create new specimens of the class while the Static Synchronized method is performed Multithreading
Why might be needed private mjyutex Multithreading
What is the difference between notify () and notifyall () Multithreading
Why are Wait () and notify () methods only in a synchronized block Multithreading
What is the difference between the Wait () method with the parameter and without the parameter Multithreading
What is the difference between the methods Thread.sleep () and Thread.yld () Multithreading
How the Thread.join () method works Multithreading
What is Livelock Multithreading
How to check whether the threads holds a monitor of a certain resource Multithreading
What object is synchronization when the Static Synchronized method is called Multithreading
Why is the keyword Synchronized Multithreading
What are the differences between Volatile and atomic variables Multithreading
What are the differences between Java.util.conatomic*.compareandswap () and java.util.concurrent.atomic*.weakcompareandswap () Multithreading
Is it possible to make the main stream of the program demon Multithreading
What does it mean to "sleep" a stream Multithreading
What is FutureTask Multithreading
What are the differences between CyclicBarrier and Countdownlatch Multithreading
Is there a way to solve the problem of Race Condition Multithreading
How to stop a thread Multithreading
Why is it not recommended to use the Thread.stop () method Multithreading
What happens when an exception is thrown out in the stream Multithreading
What is the difference between Interrupted () and Isinterrupted () Multithreading
What is a "thread pool" Multithreading
What size should there be a thread pool Multithreading
What will happen if the turn of the thread pool is already filled, but a new task is served Multithreading
What is the difference between the Submit () and execute () methods in the thread pool Multithreading
What are the differences between the CTEK (stack) and a heap (heap) in terms of multi -use Multithreading
How to share data between two threads Multithreading
How to get a dump stream Multithreading
What is Threadlocal-cross Multithreading
What are the differences between Synchronized and Reentrantlock Multithreading
What is a "blocking method" Multithreading
What is "Framwork for Fork/Join" Multithreading
What is Double Checked Locking Singleton Multithreading
How to create a streamline Singleton Multithreading
How are the immutable objects useful Multithreading
What is Busy Spin Multithreading
List the principles that you follow in multi -seating programming Multithreading
What are the types of logs Logging
What parts are the log4j journaling system Logging
What is Logger in LOG4J Logging
What is Appender in LOG4J Logging
What is Layout in LOG4J Logging
List the levels of journaling in LOG4J, What are the procedure for their priority Logging
What are the methods of configuration log4j Logging
What is SQL-infection Databases
What are the NOSQL database Databases
What is charming Databases
What are the basic properties of the transaction Databases
When full scanning of data set is more profitable for index access Databases
Does it make sense to index data that have a small number of possible values Databases
What is the difference between cluster and non -class indexes Databases
What types of indices exist Databases
What are the types of connections in the database, give examples Databases
What is alternative (alternate) key Databases
What is a potential (Candidate) key Databases
What is a composite (composite) key Databases
What is a simple key Databases
What is a "database management system" Databases
Who calls the controller methods No
What is Lombok? General
Why are the functional interfaces of Unaryoprator, Doubleunaryoprator, IntunaryOperator, Longunaryoprator Java 8
Tell me about your background General
What is D in Solid? General
Tell me about your most interesting project General
What is the easiest way to implement caching General
What is the difference between static and dynamic binding in Java OOP
What is Lombok General
What is TDD General
What is the relationship between JS and Java General
What is your total experience in Java General
Tell me why are you in java General
Where he was engaged in programming General
Where did you study General
How you evaluate yourself General
Which prompted to dwell on another programming language General
How much do you do java General
In what university did you study General
Did Java do somewhere else General
Caching only works with databases or not General
What is the caching for General
What languages do you know that use byte code General
What interesting tasks had to be solved General
What goals do you set for yourself General
What are the approaches to organizing the development process General
How do you use SOLID principle of openness-covering when designing General
Tell me about how you understand the principles of Solid based on your experience General
What position I would like to claim General
How you estimate your level General
What tasks did the patterns solved Patterns
Where you can use singleton Patterns
What patterns used besides Singleton Patterns
What is the advantage of the Builder pattern over the constructor Patterns
Whether you use the Comand pattern in work Patterns
Why do you need a pattern Command Patterns
Which structure acts as quickly as possible to the Comand pattern than it can be replaced Patterns
Tell me something about microservice interaction Patterns
What are the pluses of microservices before the monolith Patterns
As if organized the interaction of several services Patterns
What synchronization channels used to organize the interaction of several services Patterns
What design patterns do you use Patterns
Tell me about your design experience Patterns
What are design patterns Patterns
What is the lack of patterns Patterns
What is the difference between the Builder and Facade design template Patterns
What teams do you use in Git Git
Why are you needed versions control systems? Git
What are the general branching strategies do you know Git
How to drain two different branches Git
What is the difference between the approaches of Trunk BASD and Feature Branch Git
What tests do you write and how Testing
What is the difference between unit tests and integration Testing
What is unit testing Testing
What are restrictions in SQL SQL
What are stored procedures and what method of calling through JDBC SQL
What is Join SQL
What Merge does SQL
Why is SQL HAVING SQL
Tell me about the full syntax of Select in a relational database SQL
What are triggers in a relational database SQL
What is a cursor in a relational database SQL
What are the SQL operators SQL
What does NULL mean in SQL SQL
What is a “temporary table”, for which it is used SQL
What is a “performance”, View, and why it is used SQL
Life cycle Maven Tools
Tell me about the structure of the POM file in the Maven packages manager. Tools
What is the Dependence Management section for Tools
What is the difference between Kubernetes Docker Tools
How Docker differs from a virtual machine Tools
What is Message Broker Tools
What is Swagger for Tools
What do you use Mavel or Gradeel when assembling the project Frameworks
Tell me about transitivity Frameworks
What is XML XML
What is XSD scheme XML
What is DTD XML
How the Well-Formed XML differs from Valid XML XML
What is the "namespace" in XML XML
What types exist in XSD XML
What are the XML reading methods, describe the strengths and weaknesses of each method XML
When to use DOM, and when SAX, Stax analyzers XML
What are the ways of recording XML XML
What is JAXP XML
What is XSLT XML
What is UML what is a “diagram”, “notation” and “metamodel” in UML UML
What are the types of diagrams UML
What types of relationships exist in the structural diagram of classes UML
What will happen if in ApplicationContext you try to get the same bin Spring
Where and when used Prototype Spring
Which default Scope is used in Spring Spring
Where could Prototype be used Spring
What is the difference in repository annotations, Component, Controller, Service Spring
What is the difference between RestController and Controller Spring
Where the Bean annotation is used Spring
What are the methods of configuration Spring applications Spring
Tell the structure of Framework Collection Spring
What the largest project did you do using Spring Spring
How to create singleton-tin when starting a Spring application Spring
What types of proxies do you know Spring
The difference in annotations Service, Repository, Controller Spring
How to quickly make a rest service Spring
What is the difference between RestController from Controller Spring
What is the BEAN annotation for Spring
Why do you need a Spring Framework Spring
How to write a web application on Java Spring
How SOAP differs from REST Spring
How to write a Delete method Spring
What is JWT for Spring
What is the difference between authentication and authorization Spring
What is the life cycle of an object that creates Spring Spring
What is the difference between Spring Component, Repository and Service Abstracts Spring
What is the difference between the component and bina Spring
What is the difference between Filters, Interceptors, and Listeners in Spring Spring
What does the SCAN component do Spring
How many contexts can be in Spring Spring
Is it possible to create two singleton in Spring. Spring
How the context works in Spring Spring
How can you create Servlett in Spring'e Spring
How to create a controller in Spring Spring
Now in Spring it is not necessary to indicate the AbowireD annotation, why is it so Spring
What configuration will be more priority: XML, Java or Annotation Spring
Which of the configuration, XML, Java Annotation, you prefer more Spring
What configuration would be removed Spring
Where it is more convenient to use Java configuration, and where is XML configuration Spring
What is Spring Framework Spring
Tell me what is Inversion of Control Spring
What types of implementation of addiction do you know Spring
What areas of visibility in Spring you know Spring
What is Spring IOC container in Spring. Spring
What IOC implementations know Spring
How do you use Dependency Injection Spring
Request We can use in all Spring applications Spring
What Scope can be used for any application Spring
What is the difference between Request Mapping and Put Mapping Spring
Why REST is needed Spring
As a client can understand what came to the browser from the server Spring
How Dispatcher Servlet "understands" which method to call Spring
What is http type Spring
How dependency Injection can be applied to Spring Bean Spring
What is a context Spring
What is Scope Spring
What we need to make Spring MVC earn Spring
Can it turn out so that there is no controller in the context Spring
What can be returned data types in Spring MVC Spring
What is the difference between IOC and Dependency Injection Spring
What does Dependency Injection give us Spring
Have you heard anything about Spring MVC Spring
What are the advantages of the sergete technology over CGI Common Gateway Interface Servlets
What is the structure of the web project Servlets
What is the "Container of the Servlets" Servlets
Why do you need application servers if there are server containers Servlets
As a serviceman container controls the life cycle of the Serlet, when and what methods are called Servlets
What is a "deployment descriptor" Servlets
What actions need to be done when creating Servlets Servlets
In which case is it required to override the service() method Servlets
Does it make sense to determine the constructor for the servlet Servlets

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