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>();
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();

//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);
}
}

来源：https://www.cnblogs.com/hanfengyeqiao/p/9471694.html