code: public static FastByteArrayOutputStream read(InputStream in) throws IORuntimeException {
  		final FastByteArrayOutputStream out = new FastByteArrayOutputStream();
  		copy(in, out);
  		return out;
  	}
docs: 从流中读取内容，读到输出流中
  
  @param in 输入流
  @return 输出流
  @throws IORuntimeException IO异常