问题描述：
使用httpClient时候，出现java.io.IOException: Attempted read from closed stream.
原始代码：
1 public static String postJosn(String url, String jsonString) throws Exception { 2 3 SSLContext sslContext = SSLContexts.custom().useTLS().build(); 4 SSLConnectionSocketFactory f = new SSLConnectionSocketFactory(sslContext, new String[] { "TLSv1.2" }, null, 5 null); 6 CloseableHttpClient client = HttpClients.custom().setSSLSocketFactory(f).build(); 7 // 设置请求超时时间 15秒 8 //client.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 15000); 9 HttpPost myPost = new HttpPost(url); 10 myPost.setHeader(HTTP.CONTENT_TYPE, "application/json;charset=utf-8"); 11 myPost.setHeader("charset", "utf-8"); 12 13 StringEntity s = new StringEntity(jsonString, "utf-8"); 14 s.setContentEncoding("UTF-8"); 15 s.setContentType("application/json;charset=utf-8"); 16 myPost.addHeader("Content-Type", "application/json;charset=utf-8"); 17 myPost.setEntity(s); 18 19 HttpResponse res = client.execute(myPost); 20 HttpEntity entity = res.getEntity(); 21 //myPost.releaseConnection(); 22 log.info(EntityUtils.toString(entity, "utf-8"));; 23 return EntityUtils.toString(entity, "utf-8"); 24 }
原因分析：
EntityUtils.toString(HttpEntity entity, String defaultCharset)方法中操作的是流数据，流数据是一次性数据所以同一个HttpEntity不能使用多次该方法.
源码：
