Java生成CSV文件实例详解

本文实例主要讲述了Java生成CSV文件的方法，具体实现步骤如下：

1、新建CSVUtils.java文件：

package com.saicfc.pmpf.internal.manage.utils;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.beanutils.BeanUtils;

/**
* 文件操作
*/
public class CSVUtils {

/**
* 生成为CVS文件
* @param exportData
*       源数据List
* @param map
*       csv文件的列表头map
* @param outPutPath
*       文件路径
* @param fileName
*       文件名称
* @return
*/
@SuppressWarnings("rawtypes")
public static File createCSVFile(List exportData, LinkedHashMap map, String outPutPath,
String fileName) {
File csvFile = null;
BufferedWriter csvFileOutputStream = null;
try {
File file = new File(outPutPath);
if (!file.exists()) {
file.mkdir();
}
//定义文件名格式并创建
csvFile = File.createTempFile(fileName, ".csv", new File(outPutPath));
System.out.println("csvFile：" + csvFile);
// UTF-8使正确读取分隔符","
csvFileOutputStream = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
csvFile), "UTF-8"), 1024);
System.out.println("csvFileOutputStream：" + csvFileOutputStream);
// 写入文件头部
for (Iterator propertyIterator = map.entrySet().iterator(); propertyIterator.hasNext();) {
java.util.Map.Entry propertyEntry = (java.util.Map.Entry) propertyIterator.next();
csvFileOutputStream
.write(""" + (String) propertyEntry.getValue() != null ? (String) propertyEntry
.getValue() : "" + """);
if (propertyIterator.hasNext()) {
csvFileOutputStream.write(",");
}
}
csvFileOutputStream.newLine();
// 写入文件内容
for (Iterator iterator = exportData.iterator(); iterator.hasNext();) {
Object row = (Object) iterator.next();
for (Iterator propertyIterator = map.entrySet().iterator(); propertyIterator
.hasNext();) {
java.util.Map.Entry propertyEntry = (java.util.Map.Entry) propertyIterator
.next();
csvFileOutputStream.write((String) BeanUtils.getProperty(row,
(String) propertyEntry.getKey()));
if (propertyIterator.hasNext()) {
csvFileOutputStream.write(",");
}
}
if (iterator.hasNext()) {
csvFileOutputStream.newLine();
}
}
csvFileOutputStream.flush();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
csvFileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return csvFile;
}

/**
* 下载文件
* @param response
* @param csvFilePath
*       文件路径
* @param fileName
*       文件名称
* @throws IOException
*/
public static void exportFile(HttpServletResponse response, String csvFilePath, String fileName)
throws IOException {
response.setContentType("application/csv;charset=UTF-8");
response.setHeader("Content-Disposition",
"attachment; filename=" + URLEncoder.encode(fileName, "UTF-8"));

InputStream in = null;
try {
in = new FileInputStream(csvFilePath);
int len = 0;
byte[] buffer = new byte[1024];
response.setCharacterEncoding("UTF-8");
OutputStream out = response.getOutputStream();
while ((len = in.read(buffer)) > 0) {
out.write(new byte[] { (byte) 0xEF, (byte) 0xBB, (byte) 0xBF });
out.write(buffer, 0, len);
}
} catch (FileNotFoundException e) {
System.out.println(e);
} finally {
if (in != null) {
try {
in.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
}

/**
* 删除该目录filePath下的所有文件
* @param filePath
*      文件目录路径
*/
public static void deleteFiles(String filePath) {
File file = new File(filePath);
if (file.exists()) {
File[] files = file.listFiles();
for (int i = 0; i < files.length; i++) {
if (files[i].isFile()) {
files[i].delete();
}
}
}
}

/**
* 删除单个文件
* @param filePath
*     文件目录路径
* @param fileName
*     文件名称
*/
public static void deleteFile(String filePath, String fileName) {
File file = new File(filePath);
if (file.exists()) {
File[] files = file.listFiles();
for (int i = 0; i < files.length; i++) {
if (files[i].isFile()) {
if (files[i].getName().equals(fileName)) {
files[i].delete();
return;
}
}
}
}
}

/**
* 测试数据
* @param args
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
public static void main(String[] args) {
List exportData = new ArrayList<Map>();
Map row1 = new LinkedHashMap<String, String>();
row1.put("1", "11");
row1.put("2", "12");
row1.put("3", "13");
row1.put("4", "14");
exportData.add(row1);
row1 = new LinkedHashMap<String, String>();
row1.put("1", "21");
row1.put("2", "22");
row1.put("3", "23");
row1.put("4", "24");
exportData.add(row1);
LinkedHashMap map = new LinkedHashMap();
map.put("1", "第一列");
map.put("2", "第二列");
map.put("3", "第三列");
map.put("4", "第四列");

String path = "c:/export/";
String fileName = "文件导出";
File file = CSVUtils.createCSVFile(exportData, map, path, fileName);
String fileName2 = file.getName();
System.out.println("文件名称：" + fileName2);
}
}

2、调用createCSVFile方法生成CSV文件

String name = "银行退款数据";
List exportData = new ArrayList();
LinkedHashMap datamMap = null;
for (Iterator iterator = refundList.iterator(); iterator.hasNext();) {
HashMap map = (HashMap) iterator.next();
datamMap = new LinkedHashMap();
datamMap.put("1", map.get("merOrderId"));
datamMap.put("2",DateUtil.convertDateToString("yyyyMMdd", (Date) map.get("orderTime")));
BigDecimal amount = (BigDecimal) map.get("amount");
String amountString = amount.divide(new BigDecimal(10)).toPlainString();
datamMap.put("3", amountString);
datamMap.put("4", map.get("remark") != null ? map.get("remark") : "");
exportData.add(datamMap);
}
LinkedHashMap map = new LinkedHashMap();
map.put("1", "订单号");
map.put("2", "支付日期");
map.put("3", "退货现金金额（整数金额 单位：分）");
map.put("4", "退货原因");
File file = CSVUtils.createCSVFile(exportData, map, filePath, name);//生成CSV文件
fileName = file.getName();
CSVUtils.exportFile(response, filePath + fileName, fileName);//下载生成的CSV文件