HttpClient 模拟登陆，保持会话并进行后续操作

package cc.unmi.httpclient;

import org.apache.commons.httpclient.Cookie;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.httpclient.cookie.CookiePolicy;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.junit.Test;

public class HttpClientLogin {

public static void main(String[] args){
//登陆 Url
String loginUrl = "http://localhost/unmi/login.html";

//需登陆后访问的 Url
String dataUrl = "http://localhost/unmi/user_info.html?userid=123456";

HttpClient httpClient = new HttpClient();

//模拟登陆，按实际服务器端要求选用 Post 或 Get 请求方式
PostMethod postMethod = new PostMethod(loginUrl);

//设置登陆时要求的信息，一般就用户名和密码，验证码自己处理了
NameValuePair[] data = {
new NameValuePair("username", "Unmi"),
new NameValuePair("password", "123456"),
new NameValuePair("code", "anyany")
};
postMethod.setRequestBody(data);

try {
//设置 HttpClient 接收 Cookie,用与浏览器一样的策略
httpClient.getParams().setCookiePolicy(CookiePolicy.BROWSER_COMPATIBILITY);
httpClient.executeMethod(postMethod);

//获得登陆后的 Cookie
Cookie[] cookies=httpClient.getState().getCookies();
String tmpcookies= "";
for(Cookie c:cookies){
tmpcookies += c.toString()+";";
}

//进行登陆后的操作
GetMethod getMethod = new GetMethod(dataUrl);

//每次访问需授权的网址时需带上前面的 cookie 作为通行证
getMethod.setRequestHeader("cookie",tmpcookies);

//你还可以通过 PostMethod/GetMethod 设置更多的请求后数据
//例如，referer 从哪里来的，UA 像搜索引擎都会表名自己是谁，无良搜索引擎除外
postMethod.setRequestHeader("Referer", "http://unmi.cc");
postMethod.setRequestHeader("User-Agent","Unmi Spot");

httpClient.executeMethod(getMethod);

//打印出返回数据，检验一下是否成功
String text = getMethod.getResponseBodyAsString();
System.out.println(text);

} catch (Exception e) {
e.printStackTrace();
}
}
}

HttpClient client = new HttpClient();

// 1
client.getState().setCredentials(
new AuthScope("unmi.cc", 80, AuthScope.ANY_REALM),
new UsernamePasswordCredentials("username", "password")
);

// 2
client.getParams().setAuthenticationPreemptive(true);

// 3
GetMethod getMothod = new GetMethod("http://unmi.cc/twitter");

// 4
getMothod.setDoAuthentication( true );

// 5
int status = client.executeMethod( getMothod );