输入输出流拷贝文件+资源关闭

package jess.day13;

import org.junit.Test;

import java.io.*;


public class CopyStream {
    
    public void copyFileStream(String inPath, String outPath) {
        InputStream inputStream = null;
        OutputStream outputStream = null;
        // 容器 每次传输1K
        byte[] b = new byte[1024];
        int len = 0;
        try {
            // 构建输入输出对象
            inputStream = new FileInputStream(inPath);
            outputStream = new FileOutputStream(outPath);
            // 读取文件
            while ((len = inputStream.read(b)) != -1) {
                // 写入文件 每次从b写入 个从0 写到len
                outputStream.write(b, 0, len);
                System.out.println(len);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        // 关闭资源
        finally {
            // 判断是否为空
            if (inputStream != null) {
                try {
                    // 关闭输入流
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (outputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    @Test
    public void copyTest() {
        String inPath = "E:\谷歌下载\蓝底二寸.png";
        String outPath = "D:\360软件管家\蓝底二寸.png";
        copyFileStream(inPath, outPath);
    }
}