org.springframework.util.StreamUtils

1、输入

void copy(byte[] in, OutputStream out)  int copy(InputStream in, OutputStream out)  void copy(String in, Charset charset, OutputStream out)  long copyRange(InputStream in, OutputStream out, long start, long end)  

2、输出

byte[] copyToByteArray(InputStream in)  String copyToString(InputStream in, Charset charset)  // 舍弃输入流中的内容  
int drain(InputStream in)