通过昨天对HttpClient的学习,今天封装了HttpClient类
代码如下:
package com.tp.soft.util; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.List; import java.util.Map; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.NameValuePair; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.HttpClient; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.apache.http.protocol.HTTP; public class HttpUtil { public static String postRequest(String serverPath, Map<String, String> params, String encoding){ List<NameValuePair> paramPair = new ArrayList<NameValuePair>(); if(params != null && !params.isEmpty()){ for(Map.Entry<String, String> entry : params.entrySet()){ paramPair.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } } try { HttpClient client = new DefaultHttpClient(); HttpPost post = new HttpPost(serverPath); post.setEntity(new UrlEncodedFormEntity(paramPair, HTTP.UTF_8)); HttpResponse response = client.execute(post); if(response.getStatusLine().getStatusCode() == HttpStatus.SC_OK){ BufferedReader br = new BufferedReader(new InputStreamReader(response.getEntity().getContent())); //数据 String reqData = null; String responseData = ""; while((reqData = br.readLine()) != null){ responseData += reqData; } br.close(); return responseData; } } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } return "postRequest error"; } }
然后通过调用HttpUtil类来达成与服务器交互
package com.tp.soft.app; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import android.app.Activity; import android.os.Bundle; import android.view.LayoutInflater; import android.view.Menu; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ListView; import android.widget.TextView; import com.google.gson.Gson; import com.google.gson.reflect.TypeToken; import com.tp.soft.entity.User; import com.tp.soft.util.HttpUtil; public class MainActivity extends Activity { private ListView mListView; private TextView mContentTxt; private TextView mTimeTxt; private String serverPath = "http://122.226.178.54:8080/uploadApp/LoginServlet"; private static final String ENCODING = "utf-8"; private List<User> userList; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); loadList(); mListView = (ListView) findViewById(R.id.list_id); mListView.setAdapter(new BaseAdapter() { @Override public View getView(int position, View convertView, ViewGroup parent) { if(null == convertView){ convertView = LayoutInflater.from(getApplicationContext()).inflate(R.layout.item, null); } TextView textView = (TextView) convertView.findViewById(R.id.contentTxt); textView.setText(userList.get(position).getUsername()); return convertView; } @Override public long getItemId(int position) { return position; } @Override public Object getItem(int position) { return position; } @Override public int getCount() { return userList.size(); } }); } private List<User> loadList() { Map<String, String> params = new HashMap<String, String>(); String data = HttpUtil.postRequest(serverPath, params, ENCODING); userList = new Gson().fromJson(data, new TypeToken<List<User>>() {}.getType()); return userList; } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main, menu); return true; } }
服务器端则采用了servlet
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setCharacterEncoding("utf-8"); String uname = request.getParameter("uname"); String pwd = request.getParameter("pwd"); PrintWriter pw = response.getWriter(); Gson gson = new GsonBuilder().create(); List<User> userList = new ArrayList<User>(); User user = new User(); user.setUsername("zs"); user.setPassword("1"); userList.add(user); User user1 = new User(); user1.setUsername("lisi"); user1.setPassword("2"); userList.add(user1); String json = gson.toJson(userList); pw.print(json); }