AndroidHttpClient使用Cookie

今天想把一个用使用了HttpClient的自动签到小程序移植到Android上，还好Android的SDK自带了HttpClient的包。翻Android的文档时发现官方还提供了一个实现了HttpClient接口的AndroidHttpClient，上网搜了下没发现关于AndroidHttpClient的文章。当然也可以继续使用DefaultHttpClient，但用为Android定制的AndroidHttpClient自然更好。

下面是2个测试用的HttpServlet：

public class LogIn extends HttpServlet {

    /**
     * Processes requests for both HTTP
     * <code>GET</code> and
     * <code>POST</code> methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        request.setCharacterEncoding("utf-8");
        PrintWriter out = response.getWriter();
        HttpSession session=request.getSession();
        String info=request.getParameter("info");
     
        session.setAttribute("info", info);
        try {
            /* TODO output your page here. You may use following sample code. */
           out.println("OK");
        } finally {            
            out.close();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP
     * <code>GET</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Handles the HTTP
     * <code>POST</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Returns a short description of the servlet.
     *
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}

public class Info extends HttpServlet {

    /**
     * Processes requests for both HTTP
     * <code>GET</code> and
     * <code>POST</code> methods.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        HttpSession session=request.getSession();
        String info=(String)session.getAttribute("info");
        try {
            /* TODO output your page here. You may use following sample code. */
            if(info==null)
                out.print("null");
            else
                out.print(info);
        } finally {            
            out.close();
        }
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /**
     * Handles the HTTP
     * <code>GET</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Handles the HTTP
     * <code>POST</code> method.
     *
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /**
     * Returns a short description of the servlet.
     *
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}

主要代码在processRequest里，其他可以不用看。

访问LogIn时传一个name为info的值，这时浏览器会得到一个用于定位服务端session的cookie。然后访问Info，如果有cookie的话服务端能找到刚才你传的值并返回给你，没带cookie的话就不能找到。

Android端代码：

public class MainActivity extends Activity {

    private AndroidHttpClient mHttpclient=AndroidHttpClient.newInstance("");
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.button1).setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                new Thread(rTest).start();
            }
        });
     
    }


    private String toString(InputStream is) throws IOException{
   
        String ret="";
        InputStreamReader isr=new InputStreamReader(is);
        BufferedReader br=new BufferedReader(isr);
        String tmp=br.readLine();
        while(tmp!=null){
        ret+=tmp;
        tmp=br.readLine();
        }
        br.close();
        return ret;
    }
    
    
    
    private Runnable rTest=new Runnable() {
        
        @Override
        public void run() {
            // TODO Auto-generated method stub
    

            
            try {
                BasicHttpContext context=new BasicHttpContext();
                context.setAttribute(ClientContext.COOKIE_STORE,new BasicCookieStore());
                HttpPost httppost = new HttpPost("http://10.226.233.48:8080/WebApplication1/LogIn");
                List <NameValuePair> nvps = new ArrayList <NameValuePair>();
                nvps.add(new BasicNameValuePair("info", "你好 世界！！"));
                httppost.setEntity(new UrlEncodedFormEntity(nvps,"utf-8"));
                HttpResponse response=mHttpclient.execute(httppost,context);
                HttpEntity entity = response.getEntity();
                Log.i("kagami", MainActivity.this.toString(entity.getContent()));
                entity.consumeContent();
                HttpGet httpget2 = new HttpGet("http://10.226.233.48:8080/WebApplication1/Info");
                HttpResponse response2=mHttpclient.execute(httpget2,context);
                HttpEntity entity2 = response2.getEntity();
                Log.i("kagami", MainActivity.this.toString(entity2.getContent()));
                entity2.consumeContent();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    };
｝

AndroidHttpClient和DefaultHttpClient的区别：

AndroidHttpClient不能在主线程中execute，会抛出异常。AndroidHttpClient通过静态方法newInstance获得实例，参数是代理，不用代理的话填“”。DefaultHttpClient默认是启用Cookie的，AndroidHttpClient默认不启用Cookie，要使用的话每次execute时要加一个HttpContext参数，并且添加CookieStore。用完后别忘了close不然不能创建新实例。