在Workbook里创建Sheet

要在Workbook里创建一个Sheet，可以使用「HSSFWorkbook」类的「createSheet」方法。

createSheet
public HSSFSheet createSheet()

create an HSSFSheet for this HSSFWorkbook, adds it to the sheets and 
returns the high level representation. Use this to create new sheets. 
 
Returns:
  HSSFSheet representing the new sheet.

还有一个名称相同的「createSheet」方法，但可以指定Sheet名。

createSheet
public HSSFSheet createSheet(java.lang.String sheetname)

create an HSSFSheet for this HSSFWorkbook, adds it to the sheets and 
returns the high level representation. Use this to create new sheets. 
 
Parameters:
  sheetname - sheetname to set for the sheet. 
Returns:
  HSSFSheet representing the new sheet.

创建的Sheet作为「HSSFSheet」类对象返回。

示例程序

import java.io.*;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
 
public class POISample{
  public static void main(String[] args){
    HSSFWorkbook workbook = new HSSFWorkbook();
 
    workbook.createSheet();
    workbook.createSheet();
    workbook.createSheet("test");
 
    FileOutputStream out = null;
    try{
      out = new FileOutputStream("sample.xls");
      workbook.write(out);
    }catch(IOException e){
      System.out.println(e.toString());
    }finally{
      try {
        out.close();
      }catch(IOException e){
        System.out.println(e.toString());
      }
    }
  }
}

上面的示例程序执行后，会生成下面的「sample1.xls」文件。

如果没有设定Sheet名，会从0开始默认设定为Sheet0,Sheet1等，设定为test的话，则可以创建test这样的Sheet。