java 导出excel示例

package com.nbm.export.excel;

import java.io.ByteArrayOutputStream;

import javax.servlet.ServletOutputStream;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
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.HSSFCellUtil;
import org.apache.poi.hssf.util.Region;
import org.apache.struts2.ServletActionContext;

public class ExcelAction {

    public void exportExcel()
    {
          
            // 创建工作薄
            HSSFWorkbook wb = new HSSFWorkbook();
            
            
            HSSFCellStyle cellBorder = wb.createCellStyle();
            
            //设置边框
            cellBorder.setBorderLeft(HSSFCellStyle.BORDER_THIN);
            cellBorder.setBorderRight(HSSFCellStyle.BORDER_THIN);
            cellBorder.setBorderTop(HSSFCellStyle.BORDER_THIN);
            cellBorder.setBorderBottom(HSSFCellStyle.BORDER_THIN);
            
            //居中
            cellBorder.setAlignment(HSSFCellStyle.ALIGN_CENTER); 
            
            cellBorder.setWrapText(true);//自动换行
            
            HSSFFont font2 = wb.createFont();
            font2.setFontName("仿宋_GB2312");//字体
            font2.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);//粗体显示
            font2.setFontHeightInPoints((short) 12);//字号
            cellBorder.setFont(font2);//选择需要用到的字体格式



            HSSFSheet sheet = wb.createSheet("sheet1");
            
            //合并单元格
            Region region1 = new Region(0, (short) 0, 0, (short) 6);            
            sheet.addMergedRegion(region1);



            HSSFRow title = sheet.createRow(0);
            HSSFCell tcell = title.createCell(0);
            tcell.setCellValue("天津市蓟县穿芳峪乡刘向营村");
            setRegionStyle(sheet,  region1 , cellBorder);//设置合并单元格的样式
            
            sheet.setColumnWidth(0, 2500); //第一个参数代表列id(从0开始),第2个参数代表宽度值  参考 ："2012-08-10"的宽度为2500
            
            HSSFRow row1 = sheet.createRow(1);
            HSSFCell cell0 = row1.createCell(0);
            cell0.setCellValue("2012-11-22");
            
            HSSFRow row2 = sheet.createRow(2);
            HSSFCell row2cell0 = row2.createCell(0);
            row2cell0.setCellValue("测试自动换行，自动换行，自动换行");
            row2cell0.setCellStyle(cellBorder);
            
           
            // 输出数据流
            try
            {
                   
                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    wb.write(baos);
                    ServletActionContext.getResponse().setContentType(
                                    "application/vnd.ms-excel");
                    ServletActionContext.getResponse().setContentLength(baos.size());
                    ServletOutputStream out = ServletActionContext.getResponse()
                                    .getOutputStream();
                    baos.writeTo(out);
                    out.flush();
                   

            } catch (Exception e)
            {
                   
            }
    }
    /**设置合并后单元格样式
     * 
     * @param sheet
     * @param region
     * @param cs
     */
     private void setRegionStyle(HSSFSheet sheet, Region region , HSSFCellStyle cs) {
            int toprowNum = region.getRowFrom();
            for (int i = region.getRowFrom(); i <= region.getRowTo(); i ++) {
                HSSFRow row = HSSFCellUtil.getRow(i, sheet);
                for (int j = region.getColumnFrom(); j <= region.getColumnTo(); j++) {
                    HSSFCell cell = HSSFCellUtil.getCell(row, (short)j);
                    cell.setCellStyle(cs);
                }
            }
     }


    
}