RandomAccessFile 实现了DataOutput接口和DataInput接口。父类是Object，不继承任何的InputStream和OutStram。
public class RandomAccessFile implements DataOutput, DataInput, Closeable{
...
}
代码例子
定义一个Person类
class Person{
int id;
String name;
double height;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getHeight() {
return height;
}
public void setHeight(double height) {
this.height = height;
}
public Person() {
}
public Person(int id, String name, double height) {
this.id = id;
this.name = name;
this.height = height;
}
public void write(RandomAccessFile raf) throws Exception{
raf.writeInt(this.id);
raf.writeUTF(this.name);
raf.writeDouble(this.height);
}
public void read(RandomAccessFile raf)throws Exception{
this.id = raf.readInt();
this.name = raf.readUTF();
this.height = raf.readDouble();
}
}
RandomAccessFile 使用
public class RandomAccessFile1 {
public static void main(String[] args) throws Exception {
Person p = new Person(1,"Tom", 1.8);
RandomAccessFile raf = new RandomAccessFile("D:/temp/randomAccessFile.txt", "rw");
p.write(raf);
Person p2 = new Person();
//让读的位置重回到文件开头
raf.seek(0);
p2.read(raf);
System.out.println(p2.getId() +" " + p2.getName() +" " +p2.getHeight());
}
}
“rw”，既能读又能写
“r”，文件可读不可写