code: public static boolean copy(File src, File target) {
          try {
              if (src.isDirectory())
                  return copyDir(src, target);
              return copyFile(src, target);
          }
          catch (IOException e) {
              throw Lang.wrapThrow(e);
          }
      }
docs: 自动决定是 copy 文件还是目录
  
  @param src
  源
  @param target
  目标
  @return 是否 copy 成功