Excel Module

General Excel Module to implement Excel Download simply and fast.

Usage - Spring Boot with Rest API

Excel Module uses annotation and reflections to render excel file.

You need to use @ExcelColumn to Object to be rendered in excel file.

See below example.

Jitpack

Here, only explain how to manage dependency with gradle.

See other build tool usage from Jitpack Hompage

allprojects {
    repositories {
        maven { url 'https://jitpack.io' }
    }
}

// Use proper version
dependencies {
  implementation('com.github.lannstark:excel-download:0.1.1')
}

Server

// In ExcelDeto
// Rendered Field Order is same as Dto field order
public class ExcelDto {

  // Annotation Case 1. no headerStyle and bodyStyle
  @ExcelColumn(headerName = "User Name")
  private String name;
  
  // Annotation Case 2. use not default style, but use defined style
  @ExcelColumn(headerName = "User Age",
      headerStyle = @ExcelColumnStyle(excelCellStyleClass = DefaultExcelCellStyle.class, enumName = "BLUE_HEADER")
  )
  private int age;
  
  // Annotation Case 3. You can also configure bodyStyle style
  @ExcelColumn(headerName = "Happy BirthDay",
      bodyStyle = @ExcelColumnStyle(excelCellStyleClass = DefaultExcelCellStyle.class, enumName = "BODY")
  )
  private LocalDate birthDay;

}

If you want to config default style in class, you should use @DefaultHeaderStyle or @DefaultBodyStyle. This style will be applied to all fields having not field style in this class.

@DefaultHeaderStyle(
    style = @ExcelColumnStyle(excelCellStyleClass = DefaultExcelCellStyle.class, enumName = "BLUE_HEADER")
)
@DefaultBodyStyle(
	style = @ExcelColumnStyle(excelCellStyleClass = DefaultExcelCellStyle.class, enumName = "BODY")
)
public class ExcelDto {
	
	private String name;
    
    private int age;
    
    private LocalDate birthDay;
	
}

Additionally, There is customizing use case, not pre-defined excel cell style in DefaultExcelCellStyle.

See Customizing section

// In Controller
@RestController
public class Controller {
	
  @GetMapping("/any-url")
  public void methodName(RequestDto requestDto, HttpServletResponse response) throws IOException {
    // If you specify response type when you use axios,
    // you don't need to set HttpServletResponse contenttype. See #1 in Front with axios section
    response.setContentType("application/vnd.ms-excel");
  
    List<ExcelDto> excelDtos = someService.getRenderedData(requestDto);
    ExcelFile excelFile = new OneSheetExcelFile<>(excelDtos, ExcelDto.class);
    excelFile.write(response.getOutputStream());
  }

}

Front with axios

axios({
  method: 'GET',
  url: 'server-url',
  responseType: 'blob' // MUST NEED
})
.then(response => {
    // #1 Here, I designate type with response header, however, you can specify 'application/vnd.ms-excel'
    const url
      = window.URL.createObjectURL(new Blobk([response.data], {type : response.headers['content-type']}));
    const link = document.createElement('a');
    link.href = url;
    link.setAttribute('download', 'ExcelFile.xlsx');
    document.body.appendChild(link);
    link.click();
});

Customizing

You can create custom ExcelCellStyle with Class or Enum

If you use Class, you don't need to designate enumName of @ExcelColumnStyle

public class BlueHeaderStyle implements ExcelCellStyle {

  @Override
  public void apply(CellStyle cellStyle) {
    // Do anything you want to change style
    cellStyle.setBlaBla();
  }

} 

For convenient custom style class, we provide template style class, CustomExcelCellStyle You can set

• cell color
• 4-side borders type
• cell contents align Other features will be updated gradually.

public class BlueHeaderStyle extends CustomExcelCellStyle {

	@Override
	public void configure(ExcelCellStyleConfigurer configurer) {
		configurer.foregroundColor(223, 235, 246)
				.excelBorders(DefaultExcelBorders.newInstance(ExcelBorderStyle.THIN))
				.excelAlign(DefaultExcelAlign.CENTER_CENTER);
	}

}

@DefaultHeaderStyle(
    style = @ExcelColumnStyle(excelCellStyleClass = BlueHeaderStyle.class)
)
public class ExcelDto {

  private String field1;

}

If you use Enum, you have to specify enumName of @ExcelColumnStyle

public enum CustomCellStyle implements ExcelCellStyle {
	
  CUSTOM_HEADER(field1, field2);
  
  // Whatever fields you need to configure cell style
  private final String field1;
  private final int field2;
  
  @Override
  public void apply(CellStyle cellStyle) {
    // Do anything you want to change style with defined enum fields.
    cellStyle.setBlaBla();
  }
  
}

public class ExcelDto {

  @ExcelColumn(headerName = "Field Header Title",
      bodyStyle = @ExcelColumnStyle(excelCellStyleClass = CustomCellStyle.class, enumName = "CUSTOM_HEADER")
  )
  private String field1;

}

Kinds of Excel File

• OneSheetExcelFile
• MultiSheetExcelFile