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);
}
}
完工。