JAVA HttpClient重发、超时不生效

梦里梦外; 2022-05-24 02:27 489阅读 0赞

HttpClient真的是一个神奇的东西，版本之间差异过大，V4.3之前，V4.3以后V4.5以前，V4.5以后都几本是不兼容。所以JAVA在这一块的开发真的是十分头疼。

这位仁兄在深深的被折磨后很好的帮我们总结了[HTTP不同版本超时][HTTP]。

然而，本人在HttpClient 4.3.6版本下，试了无数次。。还是走不通。虽然已经把RequestConfig加到配置里面了，而且断点跟踪也看到配置已配好，也加在httpPost对象里面。但是，它就是不生效，我也很无奈。

所以，改用HttpUrlConnection进行发起POST请求。发现可以，代码如下。

*   其中，data是一个普通的POJO，可以转成json然后再转成String，作为请求实体。
 *   一定要养好设置编码的习惯，不管是请求内容还是返回的数据流。
 *  请求结束后一定要把可以关的都关闭。
 *  一部分代码是为了忽略SSL证书错误才写的。如果没有这个需求，去掉此段代码。

HttpsURLConnection httpUrlCoNN = null;
            OutputStream outputStrem = null;
            OutputStreamWriter outWrite = null;
            InputStream inputStream = null;
            InputStreamReader inputReader = null;
            BufferedReader bufferReader = null;
            
            String tmpLineStr = null;
            StringBuffer resultBuffer = new StringBuffer();
            
            try{
            	trustAllHttpCertifications();
            	HostnameVerifier verify = new HostnameVerifier() {
    				
    				@Override
    				public boolean verify(String arg0, SSLSession arg1) {
    					// TODO Auto-generated method stub
    					return true;
    				}
    			};
    			HttpsURLConnection.setDefaultHostnameVerifier(verify);
            	
            	String dataParam = JSON.toJSONString(data);
            	URL url = new URL(Url);
            	URLConnection urlConn = url.openConnection();
            	httpUrlCoNN = (HttpsURLConnection) urlConn;
            	httpUrlCoNN.setDoInput(true);
            	httpUrlCoNN.setDoOutput(true);
            	
            	//超时
            	int timeoutMilSec = 60000;
            	httpUrlCoNN.setConnectTimeout(timeoutMilSec);
            	httpUrlCoNN.setReadTimeout(timeoutMilSec);
            	
            	httpUrlCoNN.setUseCaches(false);
            	httpUrlCoNN.setRequestMethod("POST");
            	httpUrlCoNN.setRequestProperty("Connection", "Keep-Alive");
            	httpUrlCoNN.setRequestProperty("Accept-Charset", "UTF-8");
            	httpUrlCoNN.setRequestProperty("Content-Type", "application/json;charsert=utf-8");
            	httpUrlCoNN.setRequestProperty("Content-Length", String.valueOf(dataParam.length()));
            	
            	
            	outputStrem = httpUrlCoNN.getOutputStream();
            	outWrite = new OutputStreamWriter(outputStrem);
            	outWrite.write(dataParam.toString());
            	outWrite.flush();
            	if(httpUrlCoNN.getResponseCode() >= 300){
            		//返回错
            		log.info("httpResultCode = {}",httpUrlCoNN.getResponseCode());
            		return null;
            	}
            	//接收响应流
            	inputStream = httpUrlCoNN.getInputStream();
            	inputReader = new InputStreamReader(inputStream,"UTF-8");
            	bufferReader = new BufferedReader(inputReader);
            	
            	while((tmpLineStr = bufferReader.readLine())!= null){
            		resultBuffer.append(tmpLineStr);
            	}
            }catch(Exception e){
            	log.info("return  = {}",e.getMessage());
            }finally{
            	if(null != outWrite){
            		outWrite.close();
            	}
            	if(null != outputStrem){
            		outputStrem.close();
            	}
            	if(null != bufferReader){
            		bufferReader.close();
            	}
            	if(null != inputReader){
            		inputReader.close();
            	}
            	if(null != inputStream){
            		inputStream.close();
            	}
            	if(null != httpUrlCoNN){
            		httpUrlCoNN.disconnect();
            	}
            }

这部分代码是为了忽略SSL证书错误才写的。如果没有这个需求，去掉此段代码。

private void  trustAllHttpCertifications(){
    		TrustManager[] trustAllCerts = new TrustManager[1];
    		TrustManager tm = new miTM();
    		trustAllCerts[0] = tm;
    		SSLContext sc = null;
    		try {
    			sc = SSLContext.getInstance("SSL");
    			sc.init(null, trustAllCerts, null);
    		} catch (NoSuchAlgorithmException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} catch (KeyManagementException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    		
    		HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
    	}
    	
    	class miTM implements TrustManager,X509TrustManager{
    
    		@Override
    		public void checkClientTrusted(X509Certificate[] arg0, String arg1)
    				throws CertificateException {
    			// TODO Auto-generated method stub
    			
    		}
    
    		@Override
    		public void checkServerTrusted(X509Certificate[] arg0, String arg1)
    				throws CertificateException {
    			// TODO Auto-generated method stub
    			
    		}
    
    		@Override
    		public X509Certificate[] getAcceptedIssuers() {
    			// TODO Auto-generated method stub
    			return null;
    		}
    		
    		public boolean isServerTrusted(X509Certificate[] certs){
    			return true;
    		}
    		
    		public boolean isClientTrusted(X509Certificate[] certs){
    			return true;
    		}
    		
    	}

1）如果新建线程，然后在线程里发起http请求，一定要做超时控制。要不然，先不说会一直存在http连接，占用带宽，如果线程先于http请求断开，会导致报出SocketException。而且此时，这个报错是不可以通过IOException捕获（我也知道SocketException是继承了IOException，但是无奈人家就在这种情况下不会捕获）。你只能使用catch (Throwable e)\{\}来做处理。但是，此时，就算捕获到，但是该线程在线程池里也不能重新运行了。

2）这是经验，可以运用到其他地方：**因为HttpClient相对于HttpUrlConnection而言，只是做了一层封装。如果不同的版本都不能使配置生效的时候，可以直接使用封装之前的自己来构造。这样子可以避免版本的差异性。**

3）HTTPClient对于超时是会自动发起3次自动重连。如果你的http请求是在线程里发起的。那就需要注意一下这一部分的消耗了。可以手动在代码里把重发关闭。黄色部分。（老夫虽然用下面那代码控制了自动重发，但是无奈，没有把超时控制住，所以只能弃了这一版。）

HttpPost httpPost = new HttpPost(Url);
    		
     HttpRequestRetryHandler myRetryHandler = new HttpRequestRetryHandler() { @Override public boolean retryRequest(IOException arg0, int arg1, HttpContext arg2) { // TODO Auto-generated method stub return false; } }; int miSec = 60000;//超时时间 RequestConfig requestConf = RequestConfig.custom().setConnectTimeout(miSec).setConnectionRequestTimeout(miSec) .setSocketTimeout(miSec).build();
            
            
            
            
            CloseableHttpClient client = HttpClients.custom().setRetryHandler(myRetryHandler).build();
            StringEntity entity = new StringEntity(JSON.toJSONString(data), "utf-8");// 解决中文乱码问题
            entity.setContentEncoding("UTF-8");
            //FIXME
            entity.setContentType(MediaType.APPLICATION_JSON_VALUE);
            entity.setContentEncoding("UTF-8");
            httpPost.setEntity(entity);
            httpPost.setConfig(requestConf);
            httpPost.addHeader("Accept", MediaType.APPLICATION_JSON.toString());
            HttpResponse resp = null;
            try {
                resp = client.execute(httpPost);
                result = JSON.parseObject(resp.getEntity().getContent(),JSONObject.class);
            } catch (Throwable e) {
                //e.printStackTrace();
            	log.info(e.getMessage());
            	return null;
            }finally {
                 httpPost.releaseConnection();
                if(null != client){
    	        try {
    		      client.close();
    	        } catch (IOException e) {
    		     // TODO Auto-generated catch block
    		     e.printStackTrace();
    	        }
    	}

[HTTP]: https://www.cnblogs.com/hisunhyx/p/5028391.html