项目结构：

运行效果：

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下面是代码部分：

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/Text/src/com/b510/txt/MyFile.java

复制代码代码如下:

package com.b510.txt;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.FileReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.PrintWriter;

/**

* @author Hongten

*

* @time 2011-12-12 2011

*/

public class MyFile {

@SuppressWarnings("static-access")

public static void main(String[] args) {

MyFile myFile = new MyFile();

try {

for (int i = 0; i <  5; i++) {

myFile.creatTxtFile("test");

myFile.writeTxtFile("显示的是追加的信息" + i);

String str = myFile.readDate();

System.out.println("*********/n" + str);

}

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

private static String path = "txt/";

private static String filenameTemp;

/**

* 创建文件

*

* @throws IOException

*/

public static boolean creatTxtFile(String name) throws IOException {

boolean flag = false;

filenameTemp = path + name + ".txt";

File filename = new File(filenameTemp);

if (!filename.exists()) {

filename.createNewFile();

flag = true;

}

return flag;

}

/**

* 写文件

*

* @param newStr

* 新内容

* @throws IOException

*/

public static boolean writeTxtFile(String newStr) throws IOException {

// 先读取原有文件内容，然后进行写入操作

boolean flag = false;

String filein = newStr + "/r/n";

String temp = "";

FileInputStream fis = null;

InputStreamReader isr = null;

BufferedReader br = null;

FileOutputStream fos = null;

PrintWriter pw = null;

try {

// 文件路径

File file = new File(filenameTemp);

// 将文件读入输入流

fis = new FileInputStream(file);

isr = new InputStreamReader(fis);

br = new BufferedReader(isr);

StringBuffer buf = new StringBuffer();

// 保存该文件原有的内容

for (int j = 1; (temp = br.readLine()) != null; j++) {

buf = buf.append(temp);

// System.getProperty("line.separator")

// 行与行之间的分隔符 相当于“/n”

buf = buf.append(System.getProperty("line.separator"));

}

buf.append(filein);

fos = new FileOutputStream(file);

pw = new PrintWriter(fos);

pw.write(buf.toString().toCharArray());

pw.flush();

flag = true;

} catch (IOException e1) {

// TODO 自动生成 catch 块

throw e1;

} finally {

if (pw != null) {

pw.close();

}

if (fos != null) {

fos.close();

}

if (br != null) {

br.close();

}

if (isr != null) {

isr.close();

}

if (fis != null) {

fis.close();

}

}

return flag;

}

/**

* 读取数据

*/

public void readData1() {

try {

FileReader read = new FileReader(filenameTemp);

BufferedReader br = new BufferedReader(read);

String row;

while ((row = br.readLine()) != null) {

System.out.println(row);

}

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

public String readDate() {

// 定义一个待返回的空字符串

String strs = "";

try {

FileReader read = new FileReader(new File(filenameTemp));

StringBuffer sb = new StringBuffer();

char ch[] = new char[1024];

int d = read.read(ch);

while (d != -1) {

String str = new String(ch, 0, d);

sb.append(str);

d = read.read(ch);

}

System.out.print(sb.toString());

String a = sb.toString().replaceAll("@@@@@", ",");

strs = a.substring(0, a.length() - 1);

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

return strs;

}

}