需要一份500行的java程序，期末大作业，最好带详细注释。
- 1,张三,男2,李四,男3,小红,女
Java生成CSV文件简单操作实例
CSV是逗号分隔文件(Comma Separated Values)的首字母英文缩写，是一种用来存储数据的纯文本格式，通常用于电子表格或数据库软件。在 CSV文件中，数据“栏”以逗号分隔，可允许程序通过读取文件为数据重新创建正确的栏结构，并在每次遇到逗号时开始新的一栏。如：
123Java生成CSV文件（创建与导出封装类）
package com.yph.omp.common.util;
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.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.beanutils.BeanUtils;
import org.junit.Test;
/**
* Java生成CSV文件
*/
public class CSVUtil {
/**
* 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));
// UTF-8使正确读取分隔符","
csvFileOutputStream = new BufferedWriter(new OutputStreamWriter(
new FileOutputStream(csvFile), "GBK"), 1024);
// 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();
/*-------------------------------*/
//以下部分根据不同业务做出相应的更改
StringBuilder sbContext = new StringBuilder("");
if (null != BeanUtils.getProperty(row,(String) propertyEntry.getKey())) {
if("证件号码".equals(propertyEntry.getValue())){
//避免：身份证号码 ，读取时变换为科学记数 - 解决办法：加 \t(用Excel打开时，证件号码超过15位后会自动默认科学记数)
sbContext.append(BeanUtils.getProperty(row,(String) propertyEntry.getKey()) + "\t");
}else{
sbContext.append(BeanUtils.getProperty(row,(String) propertyEntry.getKey()));
}
}
csvFileOutputStream.write(sbContext.toString());
/*-------------------------------*/
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(HttpServletRequest request,
HttpServletResponse response, String csvFilePath, String fileName)
throws IOException {
response.setCharacterEncoding("UTF-8");
response.setContentType("application/csv;charset=GBK");
response.setHeader("Content-Disposition", "attachment; filename="
+ new String(fileName.getBytes("GB2312"), "ISO8859-1"));
InputStream in = null;
try {
in = new FileInputStream(csvFilePath);
int len = 0;
byte[] buffer = new byte[1024];
OutputStream out = response.getOutputStream();
while ((len = in.read(buffer)) > 0) {
out.write(buffer, 0, len);
}
} catch (FileNotFoundException e1) {
System.out.println(e1);
} finally {
if (in != null) {
try {
in.close();
} catch (Exception e1) {
throw new RuntimeException(e1);
}
}
}
}
/**
* 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;
}
}
}
}
}
@SuppressWarnings({ "unchecked", "rawtypes" })
@Test
public void createFileTest() {
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 = "d:/export";
String fileName = "文件导出";
File file = CSVUtil.createCSVFile(exportData, map, path, fileName);
String fileNameNew = file.getName();
String pathNew = file.getPath();
System.out.println("文件名称：" + fileNameNew );
System.out.println("文件路径：" + pathNew );
}
}
//注：BeanUtils.getProperty(row,(String) propertyEntry.getKey()) + "\t" ，只为解决数字格式超过15位后，在Excel中打开展示科学记数问题。
