本文實例主要講述了Java生成CSV文件的方法，具體實現步驟如下：
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 {
/**
* 生成為CVS文件
* @param exportData
* 源數據List
* @param map
* csv文件的列表頭map
* @param outPutPath
* 文件路徑
* @param fileName
* 文件名稱
* @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();
}
//定義文件名格式並創建
csvFile = File.createTempFile(fileName, ".csv", new File(outPutPath));
System.out.println("csvFile：" + csvFile);
// UTF-8使正確讀取分隔符","
csvFileOutputStream = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(
csvFile), "UTF-8"), 1024);
System.out.println("csvFileOutputStream：" + csvFileOutputStream);
// 寫入文件頭部
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();
// 寫入文件內容
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;
}
/**
* 下載文件
* @param response
* @param csvFilePath
* 文件路徑
* @param fileName
* 文件名稱
* @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);
}
}
}
}
/**
* 刪除該目錄filePath下的所有文件
* @param filePath
* 文件目錄路徑
*/
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();
}
}
}
}
/**
* 刪除單個文件
* @param filePath
* 文件目錄路徑
* @param fileName
* 文件名稱
*/
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;
}
}
}
}
}
/**
* 測試數據
* @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 = "文件導出";
File file = CSVUtils.createCSVFile(exportData, map, path, fileName);
String fileName2 = file.getName();
System.out.println("文件名稱：" + fileName2);
}
}
2、調用createCSVFile方法生成CSV文件
String name = "銀行退款數據";
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", "訂單號");
map.put("2", "支付日期");
map.put("3", "退貨現金金額（整數金額 單位：分）");
map.put("4", "退貨原因");
File file = CSVUtils.createCSVFile(exportData, map, filePath, name);//生成CSV文件
fileName = file.getName();
CSVUtils.exportFile(response, filePath + fileName, fileName);//下載生成的CSV文件
