实现方法
public Boolean copyFile(String srcPath, String desPath)
public Boolean copyFiles(String srcPath, String desPath)

public Boolean copyFile(String srcPath, String desPath)
这个方法当做工具,用于复制单个文件

public Boolean copyFile(String srcPath, String desPath) {
        BufferedInputStream bis = null;
        BufferedOutputStream bos = null;
        try {
            //创建文件类对象
            File srcFile = new File(srcPath);
            File desFile = new File(desPath);

            //创建节点流
            FileInputStream fis = new FileInputStream(srcFile);
            FileOutputStream fos = new FileOutputStream(desFile);

            //创建处理流
            bis = new BufferedInputStream(fis);
            bos = new BufferedOutputStream(fos);

            //处理数据
            byte[] buffer = new byte[1024 * 50];
            int len;
            while ((len = bis.read(buffer)) != -1) {
                bos.write(buffer, 0, len);
            }
            return true;
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        } finally {
            //关闭流
            if (bis != null) {

                try {
                    bis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (bos != null) {

                try {
                    bos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

public Boolean copyFiles(String srcPath, String desPath)
这个方法是具体功能逻辑实现

/**
     * 
     * @param srcPath 原文件目录
     * @param desPath 复制文件所在位置
     * @return 返回是否复制成功
     */
public Boolean copyFiles(String srcPath, String desPath) {
        //创建文件类对象
        File srcFile = new File(srcPath);
        //真正的文件目录
        String realPath = desPath + File.separator + srcFile.getName();
        File destFile = new File(realPath);

        //判断是否是文件夹
        if (srcFile.isDirectory()) {
            //如果是文件夹的话,则复制文件夹的所有文件
            //需要在目标位置创建新文件夹
            destFile.mkdirs();
            File[] files = srcFile.listFiles();
            for (File f : files) {
                String filePath = f.toString();
                String tempPath = realPath + File.separator + f.getName();
                if (f.isDirectory()) {
                    //如果文件夹里有文件夹
                    copyFiles(filePath, tempPath);
                } else {
                    copyFile(filePath, tempPath);
                }
            }
            return true;
        } else {
            copyFile(srcPath, realPath);
            return true;
        }
    }

功能演示
改代码是将gradle-5.6.4.zip文件复制到桌面,并且输出所需要的的时间

@Test
    public void test3() {
        String srcPath = "D:\\BaiduNetdiskDownload\\gradle-5.6.4.zip";
        String desPath = "C:\\Users\\Ht\\Desktop";
        long start = System.currentTimeMillis();
        copyFiles(srcPath, desPath);
        long end = System.currentTimeMillis();
        System.out.println(end - start);
    }