網站通過Excel導出數據已經成爲各種網站的一個基本功能，下面就詳細介紹下如何使用poi.jar方式來導出excel文件。具體步驟如下：
1、創建一個網站，下面我創建一個叫test的網站，然後將poi的jar包放入lib文件夾。我這裏是下載鏈接poi-2.5.1.jar.
結構目錄如下：
2、然後我們可以創建一個用來訪問的jsp界面（主要是提交到servlet，可有可無）
代碼如下：
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
</head>
<body>
<form action="excel">
<input value="提交" type="submit">
</form>
</body>
</html>
/**
* 系統數據導出Excel 生成器
* @version 1.0
*/
package com.whp.test;
import java.io.OutputStream;
import java.util.ArrayList;
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.HSSFColor;
public class ExcelFileGenerator {
private final int SPLIT_COUNT = 1500; //Excel每個工作簿的行數
private ArrayList fieldName = null; //excel標題數據集
private ArrayList fieldData = null; //excel數據內容
private HSSFWorkbook workBook = null;
/**
* 構造器
* @param fieldName 結果集的字段名
* @param data
*/
public ExcelFileGenerator(ArrayList fieldName, ArrayList fieldData) {
this.fieldName = fieldName;
this.fieldData = fieldData;
}
/**
* 創建HSSFWorkbook對象
* @return HSSFWorkbook
*/
public HSSFWorkbook createWorkbook() {
workBook = new HSSFWorkbook();
int rows = fieldData.size();
int sheetNum = 0;
if (rows % SPLIT_COUNT == 0) {
sheetNum = rows / SPLIT_COUNT;
} else {
sheetNum = rows / SPLIT_COUNT + 1;
}
for (int i = 1; i <= sheetNum; i++) {
HSSFSheet sheet = workBook.createSheet("Page " + i);
HSSFRow headRow = sheet.createRow((short) 0);
for (int j = 0; j < fieldName.size(); j++) {
HSSFCell cell = headRow.createCell((short) j);
//添加樣式
cell.setCellType(HSSFCell.CELL_TYPE_STRING);
cell.setEncoding(HSSFCell.ENCODING_UTF_16);
//添加樣式
//設置所有單元格的寬度
sheet.setColumnWidth((short)j, (short)6000);
//創建樣式(使用工作本的對象創建)
HSSFCellStyle cellStyle = workBook.createCellStyle();
//創建字體的對象
HSSFFont font = workBook.createFont();
//將字體加粗
font.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
//設置字體的顏色
short color = HSSFColor.RED.index;
font.setColor(color);
//將新設置的字體屬性放置到樣式中
cellStyle.setFont(font);
if(fieldName.get(j) != null){
cell.setCellStyle(cellStyle);
cell.setCellValue((String) fieldName.get(j));
}else{
cell.setCellStyle(cellStyle);
cell.setCellValue("-");
}
}
for (int k = 0; k < (rows < SPLIT_COUNT ? rows : SPLIT_COUNT); k++) {
HSSFRow row = sheet.createRow((short) (k + 1));
//將數據內容放入excel單元格
ArrayList rowList = (ArrayList) fieldData.get((i - 1)
* SPLIT_COUNT + k);
for (int n = 0; n < rowList.size(); n++) {
HSSFCell cell = row.createCell((short) n);
cell.setEncoding(HSSFCell.ENCODING_UTF_16);
if(rowList.get(n) != null){
cell.setCellValue((String) rowList.get(n).toString());
}else{
cell.setCellValue("");
}
}
}
}
return workBook;
}
public void expordExcel(OutputStream os) throws Exception {
workBook = createWorkbook();
workBook.write(os);
os.close();
}
}
4、創建一個名稱爲excel的servlet. ------通過getFieldName()和getFieldData()來模擬表格數據
package com.whp.test;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class excel extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try {
//初始化fieldName，fieldDate
ArrayList fieldName=getFieldName(); //excel標題數據集
ArrayList fieldData=getFieldData(); //excel數據內容
String myexcel="myexcel";
//回去輸出流
OutputStream out=response.getOutputStream();
//重置輸出流
response.reset();
//設置導出Excel報表的導出形式
response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-Disposition","attachment;filename="+myexcel+".xls");
ExcelFileGenerator efg=new ExcelFileGenerator(fieldName, fieldData);
efg.expordExcel(out);
//設置輸出形式
System.setOut(new PrintStream(out));
//刷新輸出流
out.flush();
//關閉輸出流
if(out!=null){
out.close();
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doGet(request, response);
}
//模擬提供excel中的標題數據集
public ArrayList getFieldName(){
String str[]={"姓名","學號","性別"};
ArrayList list=new ArrayList();
for(int i=0;i<str.length;i++){
list.add(str[i]);
}
return list;
}
//模擬提供excel中的標題數據內容
public ArrayList getFieldData(){
ArrayList list1=new ArrayList();
String str[][]={{"wang","01","男"},{"hai","02","男"},{"ping","03","女"}};
for(int i=0;i<str.length;i++)
{
ArrayList list=new ArrayList();
for(int j=0;j<str[0].length;j++)
{
list.add(str[i][j]);
}
list1.add(list);
}
return list1;
}
}
5、測試：
通過localhost:8080/test/excel.jsp訪問，然後點擊按鈕即可得到下載文件。
測試數據結果如下：
