在做excel导出时如何将excel直接写在输出流中

之前做excel导出时，我都是先将文件写在服务器上，然后再下载下来，后来发现原来可以直接将文件写在输出流里边。

下面是一个小demo:

package com.huaqin.fcstrp.util;

import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;

import javax.servlet.http.HttpServletResponse;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;

public class Write {
	
	private HSSFWorkbook workbook = null;
	/**
	 * 
	 * @param response 下载请求的response
	 */
	public void createExcel(HttpServletResponse response){
		
    	//创建workbook
    	workbook = new HSSFWorkbook();
    	//添加Worksheet（不添加sheet时生成的xls文件打开时会报错)
    	Sheet sheet1 = workbook.createSheet("sheet1");  
    	OutputStream out = null;
    	try {	 
    		out = response.getOutputStream();
    		String fileName = "test.xls";// 文件名
    		response.setContentType("application/x-msdownload");
    		response.setHeader("Content-Disposition", "attachment; filename="
    												+ URLEncoder.encode(fileName, "UTF-8"));
    		Row row = workbook.getSheet("sheet1").createRow(0);    //创建第一行  
	    	for(int i = 0;i < 10;i++){
	    		Cell cell = row.createCell(i);
	    		cell.setCellValue("测试数据"+i);
	    	}	
			workbook.write(out);
		} catch (Exception e) {
			e.printStackTrace();
		} finally {  
		    try {  	
		        out.close();  
		    } catch (IOException e) {  
		        e.printStackTrace();
		    }  
		}  
    }
}

调用：

/**
	 * 下载2
	 * @param request
	 * @param response
	 * @return
	 * @throws FileNotFoundException 
	 */
	@RequestMapping(value = "/download2")
	@ResponseBody
	public void download2(HttpServletRequest request,
			HttpServletResponse response) throws FileNotFoundException {
	     Write write = new Write();
	     write.createExcel(response);

	}