Java导出Excel的工具类

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion>
<groupId>com.tiglle</groupId>
<artifactId>testExcel</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>

<dependencies>
<!-- poi的包 -->
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi -->
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>3.16</version>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.0</version>
<scope>provided</scope>
</dependency>

</dependencies>

<build>
<finalName>tiglle</finalName>
<plugins>
<!-- 打包时不忽略空文件夹 -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.6</version>
<configuration>
<includeEmptyDirectories>true</includeEmptyDirectories>
</configuration>
</plugin>
</plugins>
</build>

</project>

package com.tiglle.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

import javax.servlet.http.HttpServletRequest;
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.CellStyle;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;

import com.tiglle.model.Person;

public class ExcelUtil {

/**
* 将多个文件压缩成一个文件
* @param srcfile 需要进行压缩的文件名称的数组(每个文件为所在磁盘的全路径:D:\\file\a.xls)
* @param zipfile 压缩后的文件名称
* @throws IOException
*/
public static void ZipFiles(File[] srcfile, File zipfile) throws Exception {
if(!zipfile.exists()){
zipfile.createNewFile();
}
byte[] buf = new byte[1024];
try {
ZipOutputStream out = new ZipOutputStream(new FileOutputStream(
zipfile));
for (int i = 0; i < srcfile.length; i++) {
File tempFile = srcfile[i];
FileInputStream in = new FileInputStream(tempFile);
out.putNextEntry(new ZipEntry(srcfile[i].getName()));
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
out.closeEntry();
in.close();
//删除文件,免得占用服务器内存
tempFile.delete();
}
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}

/**
* 设置下载文件的响应头和下载的文件名称
* @param response
* @param defaultFileName 默认返回浏览器的文件名
* @throws Exception
*/
public static void setResponseHeader(HttpServletResponse response,String defaultFileName) throws Exception {
response.setContentType("application/octet-stream;charset=UTF-8");
response.setHeader("Content-Disposition", "attachment;filename=" + java.net.URLEncoder.encode(defaultFileName, "UTF-8")  + ".zip");
response.addHeader("Pargam", "no-cache");
response.addHeader("Cache-Control", "no-cache");
}

/**
* 根据指定名称+自定义时间格式生成字符串
* @param name 最终下载的名称
* @param partener 指定时间格式:yyyy-MM-dd HH mm ss
* @return
*/
public static String generateName(String name,String partener){
Date date = new Date();
SimpleDateFormat format = new SimpleDateFormat(partener);
return name + format.format(date);
}

/**
* 生成Excel
* @param list 装实体类数据的list
* @param length 多少条生成一个Excel
* @param fileName 下载后的zip的名称和每个Excel的名称
* @param sheetName Excel中的选项卡的名称
* @param topCloumnNames Excel的头名称信息数组
* @param out PrintWrite对象
* @return
* @throws IOException
*/
public static List<String> toExcel(List<Person> list,int length, String fileName,String sheetName,String[] topCloumnNames, OutputStream out) throws IOException {
List<String> fileNames = new ArrayList<String>();// 用于存放生成的文件名称s
// 生成excel（一个对象一行）
for (int j = 0, n = list.size() / length + 1; j < n; j++) {
Workbook book = new HSSFWorkbook();
//创建Excel的第一页并指定名称
Sheet sheet = book.createSheet(sheetName);
//将每个xls+j用于区分
String tempFileName = fileName + "-" + j + ".xls";
//将名字纪录起来
fileNames.add(tempFileName);
FileOutputStream o = null;
try {
o = new FileOutputStream(tempFileName);
// sheet.addMergedRegion(new
// CellRangeAddress(list.size()+1,0,list.size()+5,6));
//创建头，并设置头名称
Row row = sheet.createRow(0);
for(int i=0;i<topCloumnNames.length;i++){
row.createCell(i).setCellValue(topCloumnNames[i]);
}

int m = 1;

//格式
CellStyle cellStyle = book.createCellStyle();
//居中
cellStyle.setAlignment(CellStyle.ALIGN_CENTER);

for (int i = 1, min = (list.size() - j * length + 1) > (length + 1) ? (length + 1)  : (list.size() - j * length + 1); i < min; i++) {
m++;
/*
* 根据业务映射字段
*/
Person user = list.get(length * (j) + i - 1);
Double dd = user.getMoney();
if (dd == null) {
dd = 0.0;
}
//创建数据的每一行
row = sheet.createRow(i);
Cell cell0 = row.createCell(0);
cell0.setCellStyle(cellStyle);
cell0.setCellValue(user.getId());
row.createCell(1).setCellValue(user.getName());
row.createCell(2).setCellValue(user.getAddress());
row.createCell(3).setCellValue(user.getTel());
row.createCell(4).setCellValue(dd);

}

//多创建一行
row = sheet.createRow(m);
//合并最后一行(x,y,从第几格合并,合并几格)
sheet.addMergedRegion(new CellRangeAddress(m, m, 0, 4));
} catch (Exception e) {
e.printStackTrace();
}
try {
book.write(o);
} catch (Exception ex) {
ex.printStackTrace();
} finally {
book.close();
o.flush();
o.close();
}
}
return fileNames;
}

/**
* 对外的接口
* @param request
* @param response
* @param list 装实体类数据的list
* @param zipFileName 最终生成下载的文件名和每个Excel的名称
* @param partener 是否根据上面的名称+时间格式生成最终名称,null或""不追加时间格式:yyyyMMddHHmmss
* @param dirName 项目根目录下用来装临时Excel和zip文件的文件夹名称，最终正常情况下，此文件夹始终为空
* @param count 多少条生成一个Excel
* @param sheetName 选项卡名称
* @param topColumnName excel的第一行的名称信息数组,如果数据多余名称，将显示空
* @throws Exception
*/
public static void generateExcel(HttpServletRequest request,HttpServletResponse response,List<Person> list,String zipFileName,String partener,String dirName,int count,String sheetName,String[] topColumnName) throws Exception{
//是否根据当前时间组装文件名
if(null!=partener&&"".equals(partener)){
zipFileName = ExcelUtil.generateName(zipFileName,partener);
}

//设置响应头信息
ExcelUtil.setResponseHeader(response, zipFileName);

//基于项目跟路径下的文件夹
String directoryPath = request.getRealPath("/"+dirName);
File file = new File(directoryPath);
if(!file.exists()){
file.mkdirs();
}
//每个xls文件的全路径(根据tomcat所在路径获取的,无后缀)
String fileName = directoryPath + "/" + zipFileName;

OutputStream out = response.getOutputStream();
//生成n多个Excel,并将多个xls文件名+n用于区分,返回每个生成的xls的文件全路径
List<String> fileNames = ExcelUtil.toExcel(list,count,fileName,sheetName,topColumnName,out);

//将生成的n个xls压缩成一个zip文件,并删除xls文件
File zip = new File(fileName + ".zip");// 压缩文件
File srcfile[] = new File[fileNames.size()];
for (int i = 0, n = fileNames.size(); i < n; i++) {
srcfile[i] = new File(fileNames.get(i));//根据路径生成File对象
}
//压缩成zip
ExcelUtil.ZipFiles(srcfile, zip);

//将zip写给客户端
FileInputStream inStream = new FileInputStream(zip);
byte[] buf = new byte[4096];
int readLength;
while (((readLength = inStream.read(buf)) != -1)) {
out.write(buf, 0, readLength);
}
inStream.close();
//删除zip文件,免得占用服务器内存
zip.delete();

out.flush();
out.close();
}
}

package com.tiglle.serlvet;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.tiglle.model.Person;
import com.tiglle.utils.ExcelUtil;

/**
* Servlet implementation class ExportServlet
*/
public class ExportServlet extends HttpServlet {

/**
*
*/
private static final long serialVersionUID = 1L;

@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) {
System.out.println("开始导出..........................");
List<Person> list = new ArrayList<Person>();
int count = Integer.parseInt(request.getParameter("count"));
for(int i=0;i<count;i++){
Person p = new Person(i,"名称"+i,"地址"+i,"电话"+i,i+0.0);
list.add(p);
}
try {
ExcelUtil.generateExcel(request, response, list, "测试导出", "yyyy-MM", "filesss", 20000, "测试导出", new String[]{"第一行","第二行"});
} catch (Exception e) {
e.printStackTrace();
}
}

@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) {

doGet(request, response);
}

}