Http请求保存用户的的登录状态

今天是关于怎么处理，用户登录之后，怎么保持登录状态。

HTTP 用户登录的过程

A 客户登录之，Web服务器会给该客服端产生一个SessionID

B SessionID 会随着服务器的响应结果一并返回来

C 客服端获取服务器返回来的SessionID

D 向服务器发送其他请求，要把SessionID传给服务器，服务器会去匹配该SessionID是否存在，如果存在就是登录，如果不存在，则是未登录

1 如何获取Web服务器返回来的SessionID

 /**
* 获取WeB服务器Sessionid
*/
public static void getSessionID(HttpUtils http) {
DefaultHttpClient defa = (DefaultHttpClient) http.getHttpClient();
CookieStore cookie = (CookieStore) defa.getCookieStore();
List<Cookie> list = cookie.getCookies();
for (int i = 0; i < list.size(); i++) {

String name = list.get(i).getName();//得到Sessionid Key值

if (name.equals("JESSIONID")) {

SessionClass.SessionID = list.get(i).getValue();//得到Sessionid value值
Log.i("Sessionid", SessionClass.SessionID);

break;
}
}
}

2 把获取到的Sessionid 存起来

/**
* SessionID存起来
*
* @param context
* @param sessionid
* @param http
*/
private static void setCookie(Context context) {
if (context != null) {
if (!TextUtils.isEmpty(SessionClass.SessionID)) {
BasicClientCookie cookie = new BasicClientCookie("JESSIONID",
SessionClass.SessionID);
cookie.setVersion(0);
cookie.setDomain("tr.zzapi.gson.cn");
cookie.setPath("/");
BasicCookieStore cook = new BasicCookieStore();
cook.addCookie(cookie);
http.configCookieStore(cook);

}
}
}

3 请求是带上Sessionid

HttpUtils http = SessionClass
.getHttp(SessionID_main.this);

步骤   先获得SessionID      然后 存到 本地     最后 请求带上 本地的SessionID

完整的例子

package com.xcl.android;

import java.util.List;

import org.apache.http.client.CookieStore;
import org.apache.http.cookie.Cookie;
import org.apache.http.cookie.SetCookie;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.cookie.BasicClientCookie;

import android.content.Context;
import android.text.TextUtils;
import android.util.Log;

import com.lidroid.xutils.HttpUtils;

public class SessionClass {
private static HttpUtils http = new HttpUtils();
private static String SessionID;
/**
* 单利模式 只创立一次 这个必须要
*
* @param context
* @return
*/
public static HttpUtils getHttp(Context context) {
if (http == null) {
http = new HttpUtils();
}
setCookie(context);
return http;
}

/**
* 获取WeB服务器Sessionid
*/
public static void getSessionID(HttpUtils http) {
DefaultHttpClient defa = (DefaultHttpClient) http.getHttpClient();
CookieStore cookie = (CookieStore) defa.getCookieStore();
List<Cookie> list = cookie.getCookies();
for (int i = 0; i < list.size(); i++) {

String name = list.get(i).getName();//得到Sessionid Key值

if (name.equals("JESSIONID")) {

SessionClass.SessionID = list.get(i).getValue();//得到Sessionid value值
Log.i("Sessionid", SessionClass.SessionID);

break;
}
}
}

/**
* SessionID存起来
*
* @param context
* @param sessionid
* @param http
*/
private static void setCookie(Context context) {
if (context != null) {
if (!TextUtils.isEmpty(SessionClass.SessionID)) {
BasicClientCookie cookie = new BasicClientCookie("JESSIONID",
SessionClass.SessionID);
cookie.setVersion(0);
cookie.setDomain("tr.zzapi.gson.cn");
cookie.setPath("/");
BasicCookieStore cook = new BasicCookieStore();
cook.addCookie(cookie);
http.configCookieStore(cook);

}
}
}
}

package com.xcl.android;

import java.util.List;

import org.apache.http.client.CookieStore;
import org.apache.http.cookie.Cookie;
import org.apache.http.impl.client.BasicCookieStore;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.cookie.BasicClientCookie;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import com.example.sessionid.R;
import com.lidroid.xutils.HttpUtils;
import com.lidroid.xutils.exception.HttpException;
import com.lidroid.xutils.http.RequestParams;
import com.lidroid.xutils.http.ResponseInfo;
import com.lidroid.xutils.http.callback.RequestCallBack;
import com.lidroid.xutils.http.client.HttpRequest.HttpMethod;

public class SessionID_main extends Activity {
private TextView sessionID;

private Button button;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.sessionid);
sessionID = (TextView) findViewById(R.id.text);
button = (Button) findViewById(R.id.button);
button.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
final HttpUtils http = SessionClass
.getHttp(SessionID_main.this);
RequestParams params = new RequestParams();
params.addBodyParameter("userName", "李四");
params.addBodyParameter("password", "q");
http.send(HttpMethod.POST,
"http://tr.zzapi.gson.cn/api/user/login", params,
new RequestCallBack<String>() {

@Override
public void onFailure(HttpException arg0,
String arg1) {
// TODO Auto-generated method stub

}

@Override
public void onSuccess(ResponseInfo<String> arg0) {
// TODO Auto-generated method stub

SessionClass.getSessionID(http);
}
});
}
});
}

}