HttpClient 基础实例

 

 

1. 基本

import java.io.IOException;    

import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpMethod;
import org.apache.commons.httpclient.methods.GetMethod;

public class HttpTest {   
  
    public static void main(String[] args) throws IOException   
    {   
        HttpClient client = new HttpClient();      
  
        //设置代理服务器地址和端口       
  
        //client.getHostConfiguration().setProxy("proxy_host_addr",proxy_port);   
  
        //使用GET方法，如果服务器需要通过HTTPS连接，那只需要将下面URL中的http换成https   
  
        HttpMethod method = new GetMethod("http://java.sun.com");  
        //HttpMethod method = new PostMethod("http://java.sun.com");
        
        client.executeMethod(method);   
  
        //打印服务器返回的状态     
        System.out.println(method.getStatusLine());    
        //打印返回的信息    
        System.out.println(method.getResponseBodyAsString());   
        //释放连接    
        method.releaseConnection();   
  
    }   
} 

2 .重定向

 

3. 登陆

import org.apache.commons.httpclient.*;   
  
import org.apache.commons.httpclient.cookie.*;   
  
import org.apache.commons.httpclient.methods.*;   
    

  
public class FormLoginDemo {   
  
    static final String LOGON_SITE = "localhost";   
  
    static final int    LOGON_PORT = 8080;   
  
      
  
    public static void main(String[] args) throws Exception{   
  
        HttpClient client = new HttpClient();   
  
        client.getHostConfiguration().setHost(LOGON_SITE, LOGON_PORT);   
  
         
  
       //模拟登录页面login.jsp->main.jsp   
  
        PostMethod post = new PostMethod("/main.jsp");   
  
        NameValuePair name = new NameValuePair("name", "ld");       
  
        NameValuePair pass = new NameValuePair("password", "ld");       
  
        post.setRequestBody(new NameValuePair[]{name,pass});   
  
       int status = client.executeMethod(post);   
  
        System.out.println(post.getResponseBodyAsString());   
  
        post.releaseConnection();   
  
         
  
       //查看cookie信息   
  
        CookieSpec cookiespec = CookiePolicy.getDefaultSpec();   
  
        Cookie[] cookies = cookiespec.match(LOGON_SITE, LOGON_PORT, "/", false, client.getState().getCookies());   
  
       if (cookies.length == 0) {   
  
           System.out.println("None");      
  
       } else {   
  
           for (int i = 0; i < cookies.length; i++) {   
  
               System.out.println(cookies[i].toString());      
  
           }   
  
       }   
  
       //访问所需的页面main2.jsp   
  
        GetMethod get = new GetMethod("/main2.jsp");   
  
        client.executeMethod(get);   
  
        System.out.println(get.getResponseBodyAsString());   
  
        get.releaseConnection();   
  
    }   
  
}

int statuscode = post.getStatusCode();   
  
if ((statuscode == HttpStatus.SC_MOVED_TEMPORARILY) ||   
  
    (statuscode == HttpStatus.SC_MOVED_PERMANENTLY) ||   
  
    (statuscode == HttpStatus.SC_SEE_OTHER) ||   
  
    statuscode == HttpStatus.SC_TEMPORARY_REDIRECT))    
  
  
    //读取新的URL地址   
  
    Header header = post.getResponseHeader("location");   
  
    if (header != null)   
    {   
  
        String newuri = header.getValue();   
  
        if ((newuri == null) || (newuri.equals("")))   
  
                   newuri = "/";   
  
  
        GetMethod redirect = new GetMethod(newuri);   
  
        client.executeMethod(redirect);   
  
        System.out.println("Redirect:"+   
                 redirect.getStatusLine().toString());   
  
        redirect.releaseConnection();   
  
    } else  
  
         System.out.println("Invalid redirect");   
  
   }