java 文件操作追加内容

文件操作追加内容

 

 

追加内容：

package com.cyyaw.s;

import java.io.FileWriter;

import java.io.IOException;

import java.io.RandomAccessFile;

public class AppendToFile {

     /**

      * A方法追加文件：使用RandomAccessFile

      */

     public static void appendMethodA(String fileName, String content) {

           try {

                // 打开一个随机访问文件流，按读写方式

                RandomAccessFile randomFile = new RandomAccessFile(fileName, "rw");

                // 文件长度，字节数

                long fileLength = randomFile.length();

                // 将写文件指针移到文件尾。

                randomFile.seek(fileLength);

                randomFile.writeBytes(content);

                randomFile.close();

           } catch (IOException e) {

                e.printStackTrace();

           }

     }

     /**

      * B方法追加文件：使用FileWriter

      */

     public static void appendMethodB(String fileName, String content) {

           try {

                // 打开一个写文件器，构造函数中的第二个参数true表示以追加形式写文件

                FileWriter writer = new FileWriter(fileName, true);

                writer.write(content);

                writer.close();

           } catch (IOException e) {

                e.printStackTrace();

           }

     }

     public static void main(String[] args) {

           String fileName = "d:\\a.txt";

           String content = "new append! \n\r";

           

           

           

           // 按方法A追加文件

           //AppendToFile.appendMethodA(fileName, content);

           //AppendToFile.appendMethodA(fileName, "append end.");

     }

}