Android 通过httpclient请求web服务器，并解决用户登录session保持

package com.rainet.tiis.network;

import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.CookieStore;
import org.apache.http.client.HttpClient;
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.params.HttpClientParams;
import org.apache.http.cookie.Cookie;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;

import android.util.Log;

/**
* @project: TIIS
* @Title: SimpleClient.java
* @Package com.rainet.tiis.network
* @Description: HTTP请求factory
* @author 杨贵松
* @date 2014-3-18 下午12:39:23
* @version V1.0
*/
public class SimpleClient {
private static HttpParams httpParams;
private static DefaultHttpClient httpClient;
private static String JSESSIONID; //定义一个静态的字段，保存sessionID

/**
* @Title: getHttpClient
* @author 杨贵松
* @date 2014-3-18 下午1:11:18
* @Description: 获取HttpClient
* @return
* @throws Exception
* HttpClient 返回
*/
public static HttpClient getHttpClient() throws Exception {
// 创建 HttpParams 以用来设置 HTTP 参数（这一部分不是必需的）
httpParams = new BasicHttpParams();
// 设置连接超时和 Socket 超时，以及 Socket 缓存大小
HttpConnectionParams.setConnectionTimeout(httpParams, 20 * 1000);
HttpConnectionParams.setSoTimeout(httpParams, 20 * 1000);
HttpConnectionParams.setSocketBufferSize(httpParams, 8192);
// 设置重定向，缺省为 true
HttpClientParams.setRedirecting(httpParams, true);
// 设置 user agent
String userAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.9.2) Gecko/20100115 Firefox/3.6";
HttpProtocolParams.setUserAgent(httpParams, userAgent);
// 创建一个 HttpClient 实例
// 注意 HttpClient httpClient = new HttpClient(); 是Commons HttpClient
// 中的用法，在 Android 1.5 中我们需要使用 Apache 的缺省实现 DefaultHttpClient
httpClient = new DefaultHttpClient(httpParams);
return httpClient;
}

/**
* @Title: doGet
* @author 杨贵松
* @date 2014-3-18 下午12:39:58
* @Description: doGet请求
* @param url
* @param params
* @return
* @throws Exception
* String 返回
*/
@SuppressWarnings("rawtypes")
public static String doGet(String url, Map params) throws Exception {
/* 建立HTTPGet对象 */
String paramStr = "";
if (params != null) {
Iterator iter = params.entrySet().iterator();
while (iter.hasNext()) {
Map.Entry entry = (Map.Entry) iter.next();
Object key = entry.getKey();
Object val = entry.getValue();
paramStr += paramStr = "&" + key + "=" + val;
}
}
if (!paramStr.equals("")) {
paramStr = paramStr.replaceFirst("&", "?");
url += paramStr;
}
HttpGet httpRequest = new HttpGet(url);
String strResult = "doGetError";
/* 发送请求并等待响应 */
HttpResponse httpResponse = httpClient.execute(httpRequest);
/* 若状态码为200 ok */
if (httpResponse.getStatusLine().getStatusCode() == 200) {
/* 读返回数据 */
strResult = EntityUtils.toString(httpResponse.getEntity());
} else {
strResult = "Error Response: " + httpResponse.getStatusLine().toString();
}
Log.v("strResult", strResult);
return strResult;
}

/**
* @Title: doPost
* @author 杨贵松
* @date 2014-3-18 下午12:39:38
* @Description: doPost请求
* @param url
* @param params
* @return
* @throws Exception
* String 返回
*/
public static String doPost(String url, List<NameValuePair> params) throws Exception {
/* 建立HTTPPost对象 */
HttpPost httpRequest = new HttpPost(url);
String strResult = "doPostError";
/* 添加请求参数到请求对象 */
if (params != null && params.size() > 0) {
httpRequest.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
}
if(null != JSESSIONID){
httpRequest.setHeader("Cookie", "JSESSIONID="+JSESSIONID);
}
/* 发送请求并等待响应 */
HttpResponse httpResponse = httpClient.execute(httpRequest);
/* 若状态码为200 ok */
if (httpResponse.getStatusLine().getStatusCode() == 200) {
/* 读返回数据 */
strResult = EntityUtils.toString(httpResponse.getEntity());
/* 获取cookieStore */
CookieStore cookieStore = httpClient.getCookieStore();
List<Cookie> cookies = cookieStore.getCookies();
for(int i=0;i<cookies.size();i++){
if("JSESSIONID".equals(cookies.get(i).getName())){
JSESSIONID = cookies.get(i).getValue();
break;
}
}
}
Log.v("strResult", strResult);
return strResult;
}

}