Java基础FileInputStream和FileOutpiutStream实现文件拷贝

package com.hspedu.io_;

import org.junit.Test;

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


public class TestCopyFile {

    @Test
    public void copyFile() throws IOException {
        String sourceFilePath = "E:\\JavaIO\\CopyFile\\test.txt";
        FileInputStream fileInputStream = new FileInputStream(sourceFilePath);
        int readData = 0;
        String destFilePath = "e:\\JavaIO\\CopyFile\\copy.txt";
        FileOutputStream fileOutputStream = new FileOutputStream(destFilePath);
        while ((readData = fileInputStream.read()) != -1) {
            System.out.print((char) readData);
            fileOutputStream.write(readData);
        }
        fileInputStream.close();
        fileOutputStream.close();
    }

    @Test
    public void copyPicture() throws IOException {
        String sourcePicturePath = "e:\\JavaIO\\CopyFile\\123.webp";
        FileInputStream fileInputStream = new FileInputStream(sourcePicturePath);

        String destPicturePath = "e:\\JavaIO\\CopyFile\\copy.webp";
        FileOutputStream fileOutputStream = new FileOutputStream(destPicturePath);

        int readData = 0;
        byte[] bytes = new byte[1024];

        while ((readData = fileInputStream.read(bytes)) != -1) {
            System.out.println("readData: " + readData);
            fileOutputStream.write(bytes, 0, readData);
        }

        if (fileInputStream != null) {
            fileInputStream.close();
        }
        if (fileOutputStream != null) {
            fileOutputStream.close();
        }
    }
}

文件拷贝：1.先用字节输入流读取文件；2.再用字节输出流保存文件；3.图片、视频、音频等二进制文件用字节流，文本用字符流。