文件流的练习

package com.itheima.stream;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import java.io.*;

@SpringBootTest
@RunWith(SpringJUnit4ClassRunner.class)
public class FileTest {
    /**
     *    使用字节缓冲流流出
     * @throws IOException
     */
    @Test
    public void test06() throws IOException {
        FileOutputStream stream = new FileOutputStream("C:/Users/Administrator/Desktop/远程办公/aaa.txt");
        //  建立 BufferedOutputStream
        BufferedOutputStream outputStream = new BufferedOutputStream(stream);
        String  out="BufferedOutputStream outputStream";
        outputStream.write(out.getBytes());
        outputStream.flush();
        outputStream.close();
    }

    /**
     *    使用字节缓冲流读取
     * @throws IOException
     */
    @Test
    public void test05() throws IOException {
        FileInputStream stream = new FileInputStream("C:/Users/Administrator/Desktop/远程办公/aaa.txt");
        //  建立 BufferedInputStream
        BufferedInputStream inputStream = new BufferedInputStream(stream);
        //  2.读取
        int  data=0;
        while ((data=inputStream.read())!=-1){
            System.out.println((char) data);
        }
    }

    /**
     * 演示FileOutputStream  FileInputStream 实现文件的复制
     * @throws IOException
     */
    @Test
    public void test04() throws IOException {
        FileInputStream stream = new FileInputStream("C:/Users/Administrator/Desktop/远程办公/aaa.txt");
        FileOutputStream outStream = new FileOutputStream("C:/Users/Administrator/Desktop/远程办公/aaabbb.txt",false);
        byte[] bytes=new byte[3];
        int data=0;
        while((data=stream.read(bytes))!=-1){
            outStream.write(bytes,0,data);
        }
        stream.close();
        outStream.close();
    }


    /**
     * 演示FileOutputStream  文件字节输出流
     * @throws IOException
     */
    @Test
    public void test03() throws IOException {
        FileOutputStream stream = new FileOutputStream("C:/Users/Administrator/Desktop/远程办公/aaabbb.txt",true);
        String  out ="欢乐中国年";
        stream.write(out.getBytes());
        stream.close();
    }

    /**
     * 演示FileOutputStream  文件字节输出流
     * @throws IOException
     */
    @Test
    public void test02() throws IOException {
        FileOutputStream stream = new FileOutputStream("C:/Users/Administrator/Desktop/远程办公/aaabbb.txt");
        stream.write(97);
        stream.close();
    }

    @Test
    public void test01() throws IOException {
        //文件字节输入流
        FileInputStream stream = new FileInputStream("C:/Users/Administrator/Desktop/远程办公/aaa.txt");
        byte[] bytes= new byte[2];
            int data=0;
        while((data=stream.read(bytes))!=-1){
//            stream.read()  读取出来的是它的编码,能够转化为字符  char
            System.out.println(new String(bytes,0,data));
        }
        stream.close();
    }

    /**
     * 流的分类
     * 按方向  [重点]
     *  输入流:  将<存储设备>中的内容读取到内存中
     *  硬盘  ---->>>>>  内存  input
     *
     *  内存  --->>>存储设备   output
     *
     */

    @Test
    public void test() throws IOException {
        //文件字节输入流
        FileInputStream stream = new FileInputStream("C:/Users/Administrator/Desktop/远程办公/aaa.txt");
        while(stream.read()!=-1){
//            stream.read()  读取出来的是它的编码,能够转化为字符  char
            System.out.println((char) stream.read());
        }
        stream.close();
}

}