Java-8-Features Program

Overview

This repository contains a variety of practical Java 8 programs focused on building a strong foundation in modern Java concepts. Created as a learning project by a fresher, it covers the most important Java 8 features, including functional interfaces, lambda expressions, Predicate, Consumer, Supplier, Stream API, Optional class, and date/time API. The project is well-suited for beginners or anyone looking to revise Java 8, and it's especially useful for interview practice and exploring real coding scenarios questions with hands-on coding exercises.

Project Structure

The project is organized so you can focus on one feature or concept at a time. Each folder targets a specific area of Java 8.

src/
├── org.Java8.Supplier/
│   ├── Generate_6DigitOTP...
│   ├── LoginMainClass.java
│   ├── SuppliObjectOfBook.java
│   └── ...
│
├── otherJava8Feature/
│   ├── FileUploaderMainClass.java
│   ├── MethodReferenceOperatorQuestion1.java ... 10.java
│   └── PaymentMainClass.java
│
├── StreamApi/
│   ├── CountFrequency.java
│   ├── CustomerMainClass.java
│   ├── FindEvenNo.java
│   ├── RemoveDuplicates.java
│   ├── SortingUsingStreams.java
│   └── UseOfFlattenMap.java
│
├── StreamApi.AdvanceQuestionsOnStreams/
│   ├── CustomerBasedOperationAdvanceApproach.java
│   ├── CustomerBasedOpetations.java
│   ├── Task1.java ... Task13.java
│   └── ...
│
├── StreamApi.SenerioBasedQuestion/
│   ├── Ques3CreateCommaSeperated.java
│   ├── Ques1RemoveDuplicates.java
│   ├── Ques2Filter.java
│   ├── Ques4ShortEmployeeByLastName.java
│   ├── Ques5PrvntFromExceptionIfApiReturnNull.java
│   ├── Ques6GroupingOfEmployeeBasedDepartment.java
│   ├── Ques7WordCountOfChatList.java
│   └── Ques8HighestRatedEmployee.java
│
├── timeAndDateApi/
│   ├── DateTimerExample.java
│   ├── OperationsOnDates.java
│   └── SomeOperationsOnCalculatingPeriods.java
│
├── CollectionApiImprovement/
│   ├── RemoveIfMethod.java
│   └── ReplaceAllMethod.java
│
├── optionalClass/
│   ├── PlayWithOptionalClass.java
│   └── VarifyEmailMianClass.java
│
├── org.Java8/
│   ├── BiPredicateCheckAnagram.java
│   ├── BiPredicateCheckRange.java
│   ├── Consumer_PrintLengthOfString.java
│   ├── PredicateCheckOddAndGreater.java
│   └── ...
└── module_info.java 

Description of Main Folders

• StreamApi.SenerioBasedQuestion: Real-world, scenario-based stream problems for interview and practice.
• StreamApi.AdvanceQuestionsOnStreams: Advanced and complex stream operations; suitable for deeper stream learning and interview tasks.
• org.Java8.Supplier: Programs demonstrating Java 8 Supplier interface with real-world uses (e.g., OTP generator, book objects, random data).
• otherJava8Feature: Specialized feature demos including method references and file uploaders.
• StreamApi: Core programs for learning Stream API functions—filtering, mapping, sorting, etc.
• timeAndDateApi: Using the Java 8 Date/Time API for modern date and period calculations.
• optionalClass: Safe null handling and conditional logic with Java 8 Optional.
• org.Java8: Miscellaneous Java 8 features, especially on Predicate, Consumer, and BiPredicate with focused class files.