io流笔记

输入输出字节流

父类 OutputStream（写出） IntputStream（读入）
子类 FileOutputStream FileIntputStream
简单测试

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class Main {
    public static void main(String[] args) throws IOException {
        FileOutputStream data=null;
        data=new FileOutputStream("e:/data.txt",true);
        String s="dwadawdDwadwa带娃";
        byte []a=s.getBytes();
        data.write(a);
        data.flush();
        data.close();
        FileInputStream data1=null;
        data1=new FileInputStream("e:/data.txt");
        byte []b=new byte[data1.available()];
        data1.read(b);
        String d=new String(b);
        System.out.println(d);
        data1.close();
    }
}

输入输出字符流

父类 Reader Writer
子类 FileReader FileWriter

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class Main1 {
    public static void main(String[] args) throws IOException {
        FileReader data=null;
        data=new FileReader("e:/data.txt");
        char []c=new char[100];
        data.read(c);
        String s=new String(c);
        System.out.println(s);
        data.close();
        FileWriter data1=null;
        data1=new FileWriter("e:/data.txt",true);
        String s1="dwaFaf凡人";
        data1.write(s1);
        data1.close();
    }
}

输入输出流（对象）

import java.io.*;

public class Main2 {
    public static void main(String[] args) {
        ObjectInputStream ois=null;
        ObjectOutputStream oos=null;
        try {
            oos=new ObjectOutputStream(new FileOutputStream("d:/data.bin"));
            ois=new ObjectInputStream(new FileInputStream("d:/data.bin"));
            Teacher teacher=new Teacher(3000,20);
            oos.writeObject(teacher);
            oos.flush();
            Teacher a=(Teacher)ois.readObject();
            System.out.println(a);
        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }finally {
            try {
                ois.close();
                oos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }
}

//Teacher类
import java.io.Serializable;

public class Teacher implements Serializable {
    private double salary;
    private int age;

    public Teacher(double salary, int age) {
        this.salary = salary;
        this.age = age;
    }

    @Override
    public String toString() {
        return "Teacher{" +
                "salary=" + salary +
                ", age=" + age +
                '}';
    }
}

InputStreamReader OutoutSteamWriter（字节转字符流）PrintWriter BufferedReader

import java.io.*;

public class Buffer {

    public static void main(String[] args) throws IOException {
        PrintWriter br1=new PrintWriter(new OutputStreamWriter(new FileOutputStream("d:/data.txt"),"utf-8"));
        br1.println("123456");
        br1.println("5465656");
        br1.println("6266146");
        br1.println("啊啊啊啊啊");
        br1.flush();
        br1.close();

        BufferedReader br=new BufferedReader(new InputStreamReader(new FileInputStream("d:/data.txt"),"utf-8"));
        String s=null;
        while((s=br.readLine())!=null){
            System.out.println(s);
        }
        br.close();
    }
}