HttpClient4.x 使用cookie保持会话

HttpClient4.x可以自带维持会话功能，只要使用同一个HttpClient且未关闭连接，则可以使用相同会话来访问其他要求登录验证的服务（见TestLogin()方法中的“执行get请求”部分）。

如果需要使用HttpClient池，并且想要做到一次登录的会话供多个HttpClient连接使用，就需要自己保存会话信息。因为客户端的会话信息是保存在cookie中的（JSESSIONID），所以只需要将登录成功返回的cookie复制到各个HttpClient使用即可。

使用Cookie的方法有两种，可以自己使用CookieStore来保存（见TestCookieStore()方法），也可以通过HttpClientContext上下文来维持（见TestContext()方法）。

附带HttpClient4.3示例代码 http://www.myexception.cn/program/1459749.html 。



package com.sunbin.httpSession;



import java.io.IOException;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import java.util.Map.Entry;



import org.apache.http.HeaderIterator;

import org.apache.http.HttpEntity;

import org.apache.http.HttpResponse;

import org.apache.http.NameValuePair;

import org.apache.http.ParseException;

import org.apache.http.client.CookieStore;

import org.apache.http.client.config.CookieSpecs;

import org.apache.http.client.entity.UrlEncodedFormEntity;

import org.apache.http.client.methods.HttpGet;

import org.apache.http.client.methods.HttpPost;

import org.apache.http.client.protocol.HttpClientContext;

import org.apache.http.config.Registry;

import org.apache.http.config.RegistryBuilder;

import org.apache.http.cookie.CookieSpecProvider;

import org.apache.http.impl.client.BasicCookieStore;

import org.apache.http.impl.client.CloseableHttpClient;

import org.apache.http.impl.client.HttpClients;

import org.apache.http.impl.cookie.BasicClientCookie;

import org.apache.http.impl.cookie.BestMatchSpecFactory;

import org.apache.http.impl.cookie.BrowserCompatSpecFactory;

import org.apache.http.message.BasicNameValuePair;

import org.apache.http.util.EntityUtils;

import org.junit.Test;



public class TestHttpClient {



  // 创建CookieStore实例

  static CookieStore cookieStore = null;

  static HttpClientContext context = null;

  String loginUrl = "http://127.0.0.1:8080/CwlProClient/j_spring_security_check";

  String testUrl = "http://127.0.0.1:8080/CwlProClient/account/querySubAccount.action";

  String loginErrorUrl = "http://127.0.0.1:8080/CwlProClient/login/login.jsp";



  @Test

  public void testLogin() throws Exception {

    System.out.println("----testLogin");



    // // 创建HttpClientBuilder

    // HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();

    // // HttpClient

    // CloseableHttpClient client = httpClientBuilder.build();

    // 直接创建client

    CloseableHttpClient client = HttpClients.createDefault();



    HttpPost httpPost = new HttpPost(loginUrl);

    Map parameterMap = new HashMap();

    parameterMap.put("j_username", "sunb012");

    parameterMap.put("j_password", "sunb012");

    UrlEncodedFormEntity postEntity = new UrlEncodedFormEntity(

        getParam(parameterMap), "UTF-8");

    httpPost.setEntity(postEntity);

    System.out.println("request line:" + httpPost.getRequestLine());

    try {

      // 执行post请求

      HttpResponse httpResponse = client.execute(httpPost);

      String location = httpResponse.getFirstHeader("Location")

          .getValue();

      if (location != null && location.startsWith(loginErrorUrl)) {

        System.out.println("----loginError");

      }

      printResponse(httpResponse);



      // 执行get请求

      System.out.println("----the same client");

      HttpGet httpGet = new HttpGet(testUrl);

      System.out.println("request line:" + httpGet.getRequestLine());

      HttpResponse httpResponse1 = client.execute(httpGet);

      printResponse(httpResponse1);





      // cookie store

      setCookieStore(httpResponse);

      // context

      setContext();

    } catch (IOException e) {

      e.printStackTrace();

    } finally {

      try {

        // 关闭流并释放资源

        client.close();

      } catch (IOException e) {

        e.printStackTrace();

      }

    }

  }



  @Test

  public void testContext() throws Exception {

    System.out.println("----testContext");

    // 使用context方式

    CloseableHttpClient client = HttpClients.createDefault();

    HttpGet httpGet = new HttpGet(testUrl);

    System.out.println("request line:" + httpGet.getRequestLine());

    try {

      // 执行get请求

      HttpResponse httpResponse = client.execute(httpGet, context);

      System.out.println("context cookies:"

          + context.getCookieStore().getCookies());

      printResponse(httpResponse);

    } catch (IOException e) {

      e.printStackTrace();

    } finally {

      try {

        // 关闭流并释放资源

        client.close();

      } catch (IOException e) {

        e.printStackTrace();

      }

    }

  }



  @Test

  public void testCookieStore() throws Exception {

    System.out.println("----testCookieStore");

    // 使用cookieStore方式

    CloseableHttpClient client = HttpClients.custom()

        .setDefaultCookieStore(cookieStore).build();

    HttpGet httpGet = new HttpGet(testUrl);

    System.out.println("request line:" + httpGet.getRequestLine());

    try {

      // 执行get请求

      HttpResponse httpResponse = client.execute(httpGet);

      System.out.println("cookie store:" + cookieStore.getCookies());

      printResponse(httpResponse);

    } catch (IOException e) {

      e.printStackTrace();

    } finally {

      try {

        // 关闭流并释放资源

        client.close();

      } catch (IOException e) {

        e.printStackTrace();

      }

    }

  }



  public static void printResponse(HttpResponse httpResponse)

      throws ParseException, IOException {

    // 获取响应消息实体

    HttpEntity entity = httpResponse.getEntity();

    // 响应状态

    System.out.println("status:" + httpResponse.getStatusLine());

    System.out.println("headers:");

    HeaderIterator iterator = httpResponse.headerIterator();

    while (iterator.hasNext()) {

      System.out.println("\t" + iterator.next());

    }

    // 判断响应实体是否为空

    if (entity != null) {

      String responseString = EntityUtils.toString(entity);

      System.out.println("response length:" + responseString.length());

      System.out.println("response content:"

          + responseString.replace("\r\n", ""));

    }

  }



  public static void setContext() {

    System.out.println("----setContext");

    context = HttpClientContext.create();

    Registry<CookieSpecProvider> registry = RegistryBuilder

        .<CookieSpecProvider> create()

        .register(CookieSpecs.BEST_MATCH, new BestMatchSpecFactory())

        .register(CookieSpecs.BROWSER_COMPATIBILITY,

            new BrowserCompatSpecFactory()).build();

    context.setCookieSpecRegistry(registry);

    context.setCookieStore(cookieStore);

  }



  public static void setCookieStore(HttpResponse httpResponse) {

    System.out.println("----setCookieStore");

    cookieStore = new BasicCookieStore();

    // JSESSIONID

    String setCookie = httpResponse.getFirstHeader("Set-Cookie")

        .getValue();

    String JSESSIONID = setCookie.substring("JSESSIONID=".length(),

        setCookie.indexOf(";"));

    System.out.println("JSESSIONID:" + JSESSIONID);

    // 新建一个Cookie

    BasicClientCookie cookie = new BasicClientCookie("JSESSIONID",

        JSESSIONID);

    cookie.setVersion(0);

    cookie.setDomain("127.0.0.1");

    cookie.setPath("/CwlProClient");

    // cookie.setAttribute(ClientCookie.VERSION_ATTR, "0");

    // cookie.setAttribute(ClientCookie.DOMAIN_ATTR, "127.0.0.1");

    // cookie.setAttribute(ClientCookie.PORT_ATTR, "8080");

    // cookie.setAttribute(ClientCookie.PATH_ATTR, "/CwlProWeb");

    cookieStore.addCookie(cookie);

  }



  public static List<NameValuePair> getParam(Map parameterMap) {

    List<NameValuePair> param = new ArrayList<NameValuePair>();

    Iterator it = parameterMap.entrySet().iterator();

    while (it.hasNext()) {

      Entry parmEntry = (Entry) it.next();

      param.add(new BasicNameValuePair((String) parmEntry.getKey(),

          (String) parmEntry.getValue()));

    }

    return param;

  }

}