HttpClient的超时用法小记

    HttpClient在使用中有两个超时时间，是一直接触和使用的，由于上次工作中使用httpClient造成了系统悲剧的情况，特地对它的两个超时时间进行了小小的测试，在这里记录下。

 

     测试版本为HttpClient——3.1

 

     一：连接超时：connectionTimeout

 

     1：指的是连接一个url的连接等待时间。

 

     2：设置方法为：

 

     public class TestHttpClientMain {

Java代码  

 

    /** 
     * @param args 
     */  
    public static void main(String[] args) {  
        HttpClient client = new HttpClient();  
      
        HttpMethod method = new GetMethod(  
                "http://test.com");  
        client.getHttpConnectionManager().getParams()  
                .setConnectionTimeout(3000);  
        client.getHttpConnectionManager().getParams().setSoTimeout(3000);  
        try {  
            int statusCode = client.executeMethod(method);  
            System.out.println(statusCode);  
      
            byte[] responseBody = null;  
      
            responseBody = method.getResponseBody();  
      
            String result = new String(responseBody);  
      
            System.out.println(result);  
      
        } catch (HttpException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (IOException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
    }  

 

 

     3：测试的时候，将url改为一个不存在的url：“http://test.com”

 

     4：超时时间3000ms过后，系统报出异常。

 

     org.apache.commons.httpclient.ConnectTimeoutException: The host did not accept the connection within timeout of 3000 ms

at org.apache.commons.httpclient.protocol.ReflectionSocketFactory.createSocket(ReflectionSocketFactory.java:
155
)
at org.apache.commons.httpclient.protocol.DefaultProtocolSocketFactory.createSocket(DefaultProtocolSocketFactory.java:125
)
at org.apache.commons.httpclient.HttpConnection.open(HttpConnection.java:707
)
at org.apache.commons.httpclient.HttpMethodDirector.executeWithRetry(HttpMethodDirector.java:387
)
at org.apache.commons.httpclient.HttpMethodDirector.executeMethod(HttpMethodDirector.java:171
)
at org.apache.commons.httpclient.HttpClient.executeMethod(HttpClient.java:397
)

 

 

     二：读取数据超时：soTimeout

 

     1：指的是连接上一个url，获取response的返回等待时间

 

     2：设置方法

 

     public class TestHttpClientMain {

Java代码  

    /** 
     * @param args 
     */  
    public static void main(String[] args) {  
        HttpClient client = new HttpClient();  
      
        HttpMethod method = new GetMethod(  
                "http://localhost:8080/firstTest.htm?method=test");  
        client.getHttpConnectionManager().getParams() .setConnectionTimeout(400
0);  
        client.getHttpConnectionManager().getParams().setSoTimeout(2000);  

        try {  
            int statusCode = client.executeMethod(method);  
            System.out.println(statusCode);  
      
            byte[] responseBody = null;  
      
            responseBody = method.getResponseBody();  
      
            String result = new String(responseBody);  
      
            System.out.println(result);  
      
        } catch (HttpException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        } catch (IOException e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }  
    }  

 

 

 

     3：测试的时候的连接url为我本地开启的一个url，http://localhost:8080/firstTest.htm?method=test

 

     在我这个测试url里，当访问到这个链接时，线程sleep一段时间，来模拟返回response超时。

 

     @RequestMapping(params = "method=test") //<——②

Java代码  

      public String testMethod(ModelMap model) {  
    try {  
        Thread.sleep(3000);  
    } catch (InterruptedException e) {  
        // TODO Auto-generated catch block  
        e.printStackTrace();  
    }  
          System.out.println("call testMethod method.");  
          model.addAttribute("name", "test method");  
    return "test";  
      }  

 

 

 

     4：将读取response返回超时时间设的时间比那个sleep时间短之后，运行程序给出异常：

 

      java.net.SocketTimeoutException: Read timed out

    at java.net.SocketInputStream.socketRead0(Native Method)  
    at java.net.SocketInputStream.read(Unknown Source)  
    at java.io.BufferedInputStream.fill(Unknown Source)  
    at java.io.BufferedInputStream.read(Unknown Source)  
    at org.apache.commons.httpclient.HttpParser.readRawLine(HttpParser.java:78)  
    at org.apache.commons.httpclient.HttpParser.readLine(HttpParser.java:106)  
    at org.apache.commons.httpclient.HttpConnection.readLine(HttpConnection.java:1116)  
    at org.apache.commons.httpclient.HttpMethodBase.readStatusLine(HttpMethodBase.java:1973)  
    at org.apache.commons.httpclient.HttpMethodBase.readResponse(HttpMethodBase.java:1735)  

  

 

 

 

     ok，以后再写httpClient这两个超时时间一定要加上，不加就很可能悲剧的了。