各种超时归纳整理

如果不设置超时，连接会一直占用本地线程，端口，连接客户端一多，阻塞在那里，会导致本地端口用尽及CPU压力

 

netty

            /**
             * *******************************************************************
             * 如果不设置超时，连接会一直占用本地线程，端口，连接客户端一多，阻塞在那里，会导致本地端口用尽及CPU压力
             */
            bootstrap.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 5000);

netty client 连接超时设置，如果是127.0.0.1，则会直接抛连接异常，由于192。*网络不通，故到时抛超时异常

关于netty connect异常，3个点要注意：1）connect可能直接抛出异常 2）要设置连接超时，否则网络不通一直卡着 3）connect不抛出异常，在回调中显示连接失败，netty（十五）负载均衡实践中代码处理了这1 3情况，并重连，不过好像忘了设置2

 

socket

Socket socket = new Socket(); 
socket.connect(new InetSocketAddress(ipAddress, port), 1000);//设置连接请求超时时间1s socket.setSoTimeout(5000);//设置读操作超时时间5s

 

/**
     *  Enable/disable {@link SocketOptions#SO_TIMEOUT SO_TIMEOUT}
     *  with the specified timeout, in milliseconds. With this option set
     *  to a non-zero timeout, a read() call on the InputStream associated with
     *  this Socket will block for only this amount of time.  If the timeout
     *  expires, a <B>java.net.SocketTimeoutException</B> is raised, though the
     *  Socket is still valid. The option <B>must</B> be enabled
     *  prior to entering the blocking operation to have effect. The
     *  timeout must be {@code > 0}.
     *  A timeout of zero is interpreted as an infinite timeout.
     *
     * @param timeout the specified timeout, in milliseconds.
     * @exception SocketException if there is an error
     * in the underlying protocol, such as a TCP error.
     * @since   JDK 1.1
     * @see #getSoTimeout()
     */
    public synchronized void setSoTimeout(int timeout) throws SocketException {
        if (isClosed())
            throw new SocketException("Socket is closed");
        if (timeout < 0)
          throw new IllegalArgumentException("timeout can't be negative");

        getImpl().setOption(SocketOptions.SO_TIMEOUT, new Integer(timeout));
    }

 

a read() call on the InputStream associated with
     *  this Socket will block for only this amount of time.  If the timeout
     *  expires, a <B>java.net.SocketTimeoutException</B> is raised, 

 

jdbc

DriverManager.setLoginTimeout(5);

work log  ，文中的连接url用了xxx，是真的xxx哦，然后到时间爆了超时而不是直接连接异常抛出，jdbc是jconn3-6.0.jar，sybase

/**
     * Sets the maximum time in seconds that a driver will wait
     * while attempting to connect to a database once the driver has
     * been identified.
     *
     * @param seconds the login time limit in seconds; zero means there is no limit
     * @see #getLoginTimeout
     */
    public static void setLoginTimeout(int seconds) {
        loginTimeout = seconds;
    }

 

 

httpclient

CloseableHttpClient httpClient = HttpClients.createDefault();
HttpGet httpGet=new HttpGet("http://www.baidu.com");//HTTP Get请求
RequestConfig requestConfig = RequestConfig.custom().setSocketTimeout(5000).setConnectTimeout(3000).build();//设置请求和传输超时时间
httpGet.setConfig(requestConfig);

 ConnectionPoolTimeoutException 获取连接池连接超时  

ConnectionTimeout：这定义了通过网络与服务器建立连接的超时时间。Httpclient包中通过一个异步线程去创建与服务器的socket连接，这就是该socket连接的超时时间，此处设置为3秒。  将url改为一个不存在的url，则会抛出org.apache.commons.httpclient.ConnectTimeoutException  

SocketTimeout：这定义了Socket读数据的超时时间，即从服务器获取响应数据需要等待的时间，此处设置为5秒。

https://www.javadoc.io/doc/org.apache.httpcomponents/httpclient/4.5.5/org/apache/http/client/config/RequestConfig.html

 Defines the socket timeout (SO_TIMEOUT) in milliseconds, which is the timeout for waiting for data or, put differently, a maximum period inactivity between two consecutive data packets). 不包括把数据从内核拷贝时间

java URL

            HttpURLConnection con = (HttpURLConnection) object.openConnection();
            con.setConnectTimeout();
            con.setReadTimeout();

 

 

jedis

Jedis jedis = new Jedis(ip, port, 10000);

 

 

 

 

 

 

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https://zhuanlan.zhihu.com/p/535405145