package com.demo.entity;public class Employee {private String name;private int age;private final static int LEN = 8;public Employee() {}public Employee(String name, int age) {if (name.length() > LEN) {name = name.substring(0, 8);} else {while (name.length() < LEN) {name = name + "\u0000";}}this.name = name;this.age = age;}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getAge() {return age;}public void setAge(int age) {this.age = age;}}

/*** 写文件*/
@Test
public void writeFile() throws IOException{Employee e1 = new Employee("zhangsan", 23);Employee e2 = new Employee("lisi", 24);Employee e3 = new Employee("wangwu", 25);RandomAccessFile raf0 = new RandomAccessFile("D:/Files/employee.txt", "rw");raf0.writeBytes(e1.getName());raf0.writeInt(e1.getAge());raf0.writeBytes(e2.getName());raf0.writeInt(e2.getAge());raf0.writeBytes(e3.getName());raf0.writeInt(e3.getAge());raf0.close();
}

/*** 读文件*/
@Test
public void ReadFile() throws IOException{RandomAccessFile raf1 = new RandomAccessFile("D:/Files/employee.txt", "r");int len = 8;raf1.skipBytes(12); // 跳过第一个员工的信息，其姓名8字节，年龄4字节System.out.println("第二个员工的信息：");String str = "";for (int i = 0; i < len; i++){str = str + (char)raf1.readByte();}System.out.println("name：" + str);System.out.println("age：" + raf1.readInt());System.out.println("第一个员工的信息：");raf1.seek(0);str = "";for (int i = 0; i < len; i++){str = str + (char)raf1.readByte();}System.out.println("name：" + str);System.out.println("age：" + raf1.readInt());System.out.println("第三个员工的信息：");raf1.skipBytes(12); // 跳过第二个员工的信息str = "";for (int i = 0; i < len; i++){str = str + (char)raf1.readByte();}System.out.println("name：" + str.trim());System.out.println("age：" + raf1.readInt());raf1.close();
}

第二个员工的信息：
name：lisi
age：24
第一个员工的信息：
name：zhangsan
age：23
第三个员工的信息：
name：wangwu
age：25