java 导出csv 格式,java导出csv格式文件的方法

本文实例为大家分享了java导出csv格式文件的具体代码，供大家参考，具体内容如下

导出csv格式文件的本质是导出以逗号为分隔的文本数据

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 com.alibaba.druid.util.StringUtils;

/**

* 文件操作

*/

public class CSVUtils {

/**

* 功能说明：获取UTF-8编码文本文件开头的BOM签名。

* BOM(Byte Order Mark)，是UTF编码方案里用于标识编码的标准标记。例：接收者收到以EF BB BF开头的字节流，就知道是UTF-8编码。

* @return UTF-8编码文本文件开头的BOM签名

*/

public static String getBOM() {

byte b[] = {(byte)0xEF, (byte)0xBB, (byte)0xBF};

return new String(b);

}

/**

* 生成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.mkdirs();

}

//定义文件名格式并创建

csvFile =new File(outPutPath+fileName+".csv");

file.createNewFile();

// UTF-8使正确读取分隔符","

//如果生产文件乱码，windows下用gbk，linux用UTF-8

csvFileOutputStream = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(

csvFile), "UTF-8"), 1024);

//写入前段字节流，防止乱码

csvFileOutputStream.write(getBOM());

// 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();

String str=row!=null?((String)((Map)row).get( propertyEntry.getKey())):"";

if(StringUtils.isEmpty(str)){

str="";

}else{

str=str.replaceAll("\"","\"\"");

if(str.indexOf(",")>=0){

str="\""+str+"\"";

}

}

csvFileOutputStream.write(str);

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;

}

/**

* 生成并下载csv文件

* @param response

* @param exportData

* @param map

* @param outPutPath

* @param fileName

* @throws IOException

*/

@SuppressWarnings("rawtypes")

public static void exportDataFile(HttpServletResponse response,List exportData, LinkedHashMap map, String outPutPath,String fileName) throws IOException{

File csvFile = null;

BufferedWriter csvFileOutputStream = null;

try {

File file = new File(outPutPath);

if (!file.exists()) {

file.mkdirs();

}

//定义文件名格式并创建

csvFile =new File(outPutPath+fileName+".csv");

if(csvFile.exists()){

csvFile.delete();

}

csvFile.createNewFile();

// UTF-8使正确读取分隔符","

//如果生产文件乱码，windows下用gbk，linux用UTF-8

csvFileOutputStream = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(csvFile), "UTF-8"), 1024);

//写入前段字节流，防止乱码

csvFileOutputStream.write(getBOM());

// 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();

String str=row!=null?((String)((Map)row).get( propertyEntry.getKey())):"";

if(StringUtils.isEmpty(str)){

str="";

}else{

str=str.replaceAll("\"","\"\"");

if(str.indexOf(",")>=0){

str="\""+str+"\"";

}

}

csvFileOutputStream.write(str);

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();

}

}

InputStream in = null;

try {

in = new FileInputStream(outPutPath+fileName+".csv");

int len = 0;

byte[] buffer = new byte[1024];

OutputStream out = response.getOutputStream();

response.reset();

response.setContentType("application/csv;charset=UTF-8");

response.setHeader("Content-Disposition","attachment; filename=" + URLEncoder.encode(fileName+".csv", "UTF-8"));

response.setCharacterEncoding("UTF-8");

while ((len = in.read(buffer)) > 0) {

out.write(new byte[] { (byte) 0xEF, (byte) 0xBB, (byte) 0xBF });

out.write(buffer, 0, len);

}

out.close();

} catch (FileNotFoundException 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 row1 = new LinkedHashMap();

row1.put("1", "11");

row1.put("2", "12");

row1.put("3", "13");

row1.put("4", "14");

exportData.add(row1);

row1 = new LinkedHashMap();

row1.put("1", "21");

row1.put("2", "22");

row1.put("3", "23");

row1.put("4", "24");

exportData.add(row1);

LinkedHashMap map = new LinkedHashMap();

//设置列名

map.put("1", "第一列名称");

map.put("2", "第二列名称");

map.put("3", "第三列名称");

map.put("4", "第四列名称");

//这个文件上传到路径，可以配置在数据库从数据库读取，这样方便一些！

String path = "E:/";

//文件名=生产的文件名称+时间戳

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);

}

}

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