java IO流文件拷贝文件（字节流标准写法）

public static void copyFile(String srcPath, String destPath) {

        FileInputStream fis = null;
        FileOutputStream fos = null;
        try {
            fis = new FileInputStream(srcPath);
            fos = new FileOutputStream(destPath);

            byte[] byt = new byte[1024 * 1024];
            int len = 0;
            while ((len = fis.read(byt)) != -1) {

                fos.write(byt, 0, len);
            }
        } catch (IOException e) {
            throw new RuntimeException(e);
        } finally {

            try {
                if (fis != null) {
                    fis.close();
                }
            } catch (IOException e) {
                throw new RuntimeException(e);
            } finally {
                if (fos != null) {
                    try {
                        fos.close();
                    } catch (IOException e) {
                        throw new RuntimeException(e);
                    }
                }

            }
        }

    }