Java IO之RandomAccessFile类

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Java IO中File类只是针对文件本身进行操作，若想要对文件内容进行操作，则可以用是RandomAccessFile类。

此类属于随机读取类，可以随机读取一个文件中指定位置的数据。

import java.io.File;import java.io.RandomAccessFile;public class RandomAccessFileDemo01 {public static void main(String[] args) throws Exception{//写内容到文件String path = "d:" + File.separator + "test.txt";File f1 = new File(path);RandomAccessFile raf = null;raf = new RandomAccessFile(f1, "rw");String name = null;int age = 0;name = "zhangsan";age = 30;raf.writeBytes(name);raf.writeInt(age);name = "lisi    ";age = 31;raf.writeBytes(name);raf.writeInt(age);name = "wangwu  ";age = 32;raf.writeBytes(name);raf.writeInt(age);raf.close();//读取文件File f2 = new File(path);RandomAccessFile raf2 = new RandomAccessFile(f2, "r");String name2 = null;int age2 = 0;byte b[] = new byte[8];raf2.skipBytes(12);for(int i = 0; i < b.length; i++){b[i] = raf2.readByte();}name2 = new String(b);age2 = raf2.readInt();System.out.println("第二个人的信息 --> 姓名：" + name2 + "；年龄:" + age2);raf2.close();}}