EQUAL

READING EXCEL(CSV) FILES IN A SQL- STYLE AND RETURN AN OBJECT LIST AS RESULT.

What is EQUAL ?

EQUAL is a small lib that can operate excel files in a sql-style. It includes the basic operations like read, write, update and delete.

---

How to use ?

PREPARE

• We need a bean class which is a model of excel or csv file. For example, if we want to operate an excel file that includes some books, we need a Book class with some annotations, the index should start from 0 and should match the order in excel/csv files.

  public class Book {
  
      @Column(name = "id", index = 0)
      public int id;
  
      @Column(name = "name", index = 1)
      public String name;
  
      @Column(name = "author", index = 2)
      public String author;
  
      @Column(name = "publishTime", index = 3)
      public LocalDate publishTime;
  
      public Book() {}
  
      public Book(int id, String name, String author, LocalDate publishTime) {
          this.id = id;
          this.name = name;
          this.author = author;
          this.publishTime = publishTime;
      }
  }

• ⚠️ The empty constructor is mandatory❗

• The excel file like:

---

READ

• The code should like:

  List<Book> books = Selector
      .select(Book.class)
      .from(new File("src/test/resources/Book.xlsx"))
      .where()
      .executeQuery();

• 📌 There is another function where() with Parameters: [int rowStartIndex, int numberOfRows], the rowStartIndex is where you start to read in excel file(begin from 1) and should greater or equal to 2.

WRITE

• The code should like:

  Inserter
      .insert(Book.class)
      .into(new File("src/test/resources/Book.csv"))
      .values(books)
      .range()
      .flush();

• 📌️ There is another function range() with Parameters: [int rowStartIndex, int numberOfRows], the rowStartIndex is where you start to write into the file and should greater or equal to 1.
• 📌 And for the file title, it follows this rule:

  Source File	Column Name
  Source File Exist	Not Insert Column Name
  Source File Do Not Exist	Insert Column Name

• The result should like:

  id,name,author,publishTime
  0,Notre-Dame de Paris,Victor Hugo,1831/01/14
  1,Wuthering Heights,Emily Bronte,1847/07/06
  2,The Red and the Black,Marie-Henri Beyle,1830/09/27
  3,Jean-Christophe,Romain Rolland,1912/04/18
  4,David Copperfield,Charles John Huffam Dickens,1849/02/03
  

UPDATE

DELETE