POI 操作Excel，创建上拉框

POI 操作Excel，创建下拉框

import java.io.FileOutputStream;import java.util.Date;import org.apache.poi.hssf.usermodel.DVConstraint;import org.apache.poi.hssf.usermodel.HSSFCell;import org.apache.poi.hssf.usermodel.HSSFDataValidation;import org.apache.poi.hssf.usermodel.HSSFRow;import org.apache.poi.hssf.usermodel.HSSFSheet;import org.apache.poi.hssf.usermodel.HSSFWorkbook;import org.apache.poi.hssf.util.CellRangeAddressList;public class POI{ public static void main(String [] args) {  String [] list={"东软","华信","SAP","海辉"};  new POI().createListBox(list);  return; } public void createListBox (String [] list) {  //文件初始化  HSSFWorkbook wb = new HSSFWorkbook();     HSSFSheet sheet = wb.createSheet("new sheet");         //在第一行第一个单元格，插入下拉框     HSSFRow row = sheet.createRow(0);     HSSFCell cell = row.createCell(0);         //普通写入操作     cell.setCellValue("请选择");//这是实验     //生成下拉列表         //只对（0，0）单元格有效     CellRangeAddressList regions = new CellRangeAddressList(0,0,0,0);         //生成下拉框内容     DVConstraint constraint = DVConstraint.createExplicitListConstraint(list);         //绑定下拉框和作用区域     HSSFDataValidation data_validation = new HSSFDataValidation(regions,constraint);          //对sheet页生效     sheet.addValidationData(data_validation);     //写入文件     FileOutputStream fileOut;  try {   fileOut = new FileOutputStream("workbook.xls");   wb.write(fileOut);   fileOut.close();  } catch (Exception e) {   // TODO Auto-generated catch block   e.printStackTrace();  }    //结束  System.out.println("Over"); }}