目录递归拷贝(java)

public class Test4 {
	private static long totalSize = 0;
	public static void main(String...args) throws IOException{
		File f1 = new File("E:\\TDDOWNLOAD");
		File f2 = new File("E:\\TDDOWNLOAD2");
		long start = System.currentTimeMillis();
		copy(f1, f2);
		long end = System.currentTimeMillis();
		System.out.println("拷贝总大小："+totalSize*1.0/1024/1024+"(MB), time: "+(end-start));
	}
	
	public static void copy(File f1, File f2) throws IOException{
		//如果目标不是目录，直接退出
		if(!f2.isDirectory()){
			return ;
		}
		//源文件是目录，循环所有子文件
		if(f1.isDirectory()){
			File[] subFiles = f1.listFiles();
			for(int i=0;i<subFiles.length;i++){
				String newFileName = f2.getPath()+"/"+subFiles[i].getName();
				File newFile = new File(newFileName);
				//子文件是目录则递归拷贝
				if(subFiles[i].isDirectory()){
					if(!newFile.exists()){
						newFile.mkdir();
					}else{
					}
					copy(subFiles[i], newFile);
				}else{//子文件是文件，则直接拷贝
					copy(subFiles[i],f2);
				}
			}
		}else{//源文件是文件直接拷贝
			String newFileName = f2.getPath()+"/"+f1.getName();
			File newFile = new File(newFileName);
			//是否覆盖拷贝
			/*if(newFile.exists()){
				return ;
			}*/
			newFile.createNewFile();
			FileInputStream fis = new FileInputStream(f1);
			BufferedInputStream bis = new BufferedInputStream(fis, 8192);
			FileOutputStream fos = new FileOutputStream(newFileName);
			BufferedOutputStream bos = new BufferedOutputStream(fos,8192);
			byte[] b = new byte[8192];
			int count = -1;
			while((count=bis.read(b))!=-1){
				totalSize+=count;
				bos.write(b,0,count);
			}
			bis.close();
			bos.close();
			fis.close();
			fos.close();
		}
	}
}