import java.io.*;/***//**

*

* 功能描述：创建TXT文件并进行读、写、修改操作

*

* @author KenZhang

* @version 1.0

* Creation date: 2007-12-18 - 下午06:48:45*/

public classReadWriteFile {public staticBufferedReader bufread;//指定文件路径和名称

private static String path = "D:/suncity.txt";private static File filename = newFile(path);private static String readStr ="";/***//**

* 创建文本文件.

* @throws IOException

**/

public static voidcreatTxtFile() throws IOException{if (!filename.exists()) {

filename.createNewFile();

System.err.println(filename+ "已创建！");

}

}/***//**

* 读取文本文件.

**/

public staticString readTxtFile(){

String read;

FileReader fileread;try{

fileread= newFileReader(filename);

bufread= newBufferedReader(fileread);try{while ((read = bufread.readLine()) != null) {

readStr= readStr + read+ "\r\n";

}

}catch(IOException e) {//TODO Auto-generated catch block

e.printStackTrace();

}

}catch(FileNotFoundException e) {//TODO Auto-generated catch block

e.printStackTrace();

}

System.out.println("文件内容是:"+ "\r\n" +readStr);returnreadStr;

}/***//**

* 写文件.

**/

public static voidwriteTxtFile(String newStr) throws IOException{//先读取原有文件内容，然后进行写入操作

String filein = newStr + "\r\n" + readStr + "\r\n";

RandomAccessFile mm= null;try{

mm= new RandomAccessFile(filename, "rw");

mm.writeBytes(filein);

}catch(IOException e1) {//TODO 自动生成 catch 块

e1.printStackTrace();

}finally{if (mm != null) {try{

mm.close();

}catch(IOException e2) {//TODO 自动生成 catch 块

e2.printStackTrace();

}

}

}

}/***//**

* 将文件中指定内容的第一行替换为其它内容.

*

* @param oldStr

* 查找内容

* @param replaceStr

* 替换内容*/

public static voidreplaceTxtByStr(String oldStr,String replaceStr) {

String temp= "";try{

File file= newFile(path);

FileInputStream fis= newFileInputStream(file);

InputStreamReader isr= newInputStreamReader(fis);

BufferedReader br= newBufferedReader(isr);

StringBuffer buf= newStringBuffer();//保存该行前面的内容

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

&& !temp.equals(oldStr); j++) {

buf=buf.append(temp);

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

}//将内容插入

buf =buf.append(replaceStr);//保存该行后面的内容

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

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

buf=buf.append(temp);

}

br.close();

FileOutputStream fos= newFileOutputStream(file);

PrintWriter pw= newPrintWriter(fos);

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

pw.flush();

pw.close();

}catch(IOException e) {

e.printStackTrace();

}

}/***//**

* main方法测试

* @param s

* @throws IOException*/

public static voidmain(String[] s) throws IOException {

ReadWriteFile.creatTxtFile();

ReadWriteFile.readTxtFile();

ReadWriteFile.writeTxtFile("20080808:12:13");//ReadWriteFile.replaceTxtByStr("ken", "zhang");

}

}