HttpClient 是 Apache Jakarta Common 下的子项目，可以用来提供高效的、最新的、功能丰富的支持 HTTP 协议的客户端编程工具包，并且它支持 HTTP 协议最新的版本和建议。
使用 HttpClient 需要以下 6 个步骤：
1. 创建 HttpClient 的实例
2. 创建某种连接方法的实例，在这里是 GetMethod。在 GetMethod 的构造函数中传入待连接的地址
3. 调用第一步中创建好的实例的 execute 方法来执行第二步中创建好的 method 实例
4. 读 response
5. 释放连接。无论执行方法是否成功，都必须释放连接
6. 对得到后的内容进行处理
MainActivity.java
1 package com.example.day12_01login;
2
3 import java.io.InputStream;
4 import java.net.URLEncoder;
5 import java.util.ArrayList;
6 import java.util.List;
7 import org.apache.http.HttpEntity;
8 import org.apache.http.HttpResponse;
9 import org.apache.http.NameValuePair;
10 import org.apache.http.client.HttpClient;
11 import org.apache.http.client.entity.UrlEncodedFormEntity;
12 import org.apache.http.client.methods.HttpGet;
13 import org.apache.http.client.methods.HttpPost;
14 import org.apache.http.impl.client.DefaultHttpClient;
15 import org.apache.http.message.BasicNameValuePair;
16 import com.cskaoyan.webutils.WebUtils;
17 import android.app.Activity;
18 import android.os.Bundle;
19 import android.os.Handler;
20 import android.os.Message;
21 import android.view.View;
22 import android.widget.EditText;
23 import android.widget.Toast;
24
25 public class MainActivity extends Activity {
26
27 @Override
28 protected void onCreate(Bundle savedInstanceState) {
29 super.onCreate(savedInstanceState);
30 setContentView(R.layout.activity_main);
31 }
32
33 Handler hanlder = new Handler(){
34 @Override
35 public void handleMessage(Message msg) {
36 // TODO Auto-generated method stub
37 super.handleMessage(msg);
38
39 switch (msg.what) {
40 case 1:
41 Toast.makeText(MainActivity.this, (String)msg.obj, 1).show();
42 break;
43 case 2:
44 Toast.makeText(MainActivity.this, (String)msg.obj, 0).show();
45 break;
46 default:
47 break;
48 }
49 }
50 };
51
52
53 //http client 的get请求
54 public void login(View v){
55 EditText et_username = (EditText) findViewById(R.id.et_uername);
56 EditText et_password = (EditText) findViewById(R.id.et_password);
57
58 final String username= et_username.getText().toString();
59 final String password= et_password.getText().toString();
60 //http://localhost/LoginDemo/servlet/Login
61 //发请求的线程
62 Thread thread = new Thread(){
63 public void run() {
64 String path = "http://192.168.3.30/LoginDemo/servlet/Login?username="+URLEncoder.encode(username)+"&password="+password;
65 HttpClient httpClient =null;
66 try {
67
68 httpClient = new DefaultHttpClient();
69 HttpGet httpget= new HttpGet(path);
70
71 HttpResponse httpResponse =httpClient.execute(httpget);
72
73 //conn.getResponseCode()==200
74 if(httpResponse.getStatusLine().getStatusCode()==200){
75 InputStream is=httpResponse.getEntity().getContent();
76 String text = WebUtils.gettextFromInputStream(is, null);
77 Message msg = hanlder.obtainMessage();
78 msg.what=1;
79 msg.obj=text;
80 hanlder.sendMessage(msg);
81 }
82 else {
83 Message msg = hanlder.obtainMessage();
84 msg.what=2;
85 msg.obj="连接服务器失败";
86 hanlder.sendMessage(msg);
87 }
88 } catch (Exception e) {
89 // TODO Auto-generated catch block
90 e.printStackTrace();
91 }
92 finally{
93 if (httpClient!=null) {
94 httpClient.getConnectionManager().shutdown();
95 }
96 }
97
98 };
99 };
100 thread.start();
101 }
102
103 //http client Post 请求实现
104 public void login2(View v){
105
106 EditText et_username = (EditText) findViewById(R.id.et_uername);
107 EditText et_password = (EditText) findViewById(R.id.et_password);
108
109 final String username= et_username.getText().toString();
110 final String password= et_password.getText().toString();
111
112 //http://localhost/LoginDemo/servlet/Login
113 //发请求的线程
114 Thread thread = new Thread(){
115 public void run() {
116 String path = "http://192.168.3.39/LoginDemo/servlet/Login";
117 //data = username=%E7%8E%8B%E9%81%93&password=123456
118 String data = "username="+URLEncoder.encode(username)+"&password="+password;
119 HttpClient httpClient = null;
120 try {
121 httpClient = new DefaultHttpClient();
122 HttpPost httpPost = new HttpPost(path);
123 //HttpEntity httpEntity = new StringEntity(s);
124 List<NameValuePair> parameters = new ArrayList<NameValuePair>();
125
126 NameValuePair namevp= new BasicNameValuePair("username",username );
127 parameters.add(namevp);
128 NameValuePair namevp2= new BasicNameValuePair("password",password );
129 parameters.add(namevp2);
130 HttpEntity httpEntity = new UrlEncodedFormEntity(parameters,"utf-8");
131 httpPost.setEntity(httpEntity);
132
133 HttpResponse httpResponse =httpClient.execute(httpPost);
134 if(httpResponse.getStatusLine().getStatusCode()==200){
135 InputStream is= httpResponse.getEntity().getContent();
136 String text = WebUtils.gettextFromInputStream(is, null);
137 is.close();
138 Message msg = hanlder.obtainMessage();
139 msg.what=1;
140 msg.obj=text;
141 hanlder.sendMessage(msg);
142 }
143 else {
144 Message msg = hanlder.obtainMessage();
145 msg.what=2;
146 msg.obj="连接服务器失败";
147 hanlder.sendMessage(msg);
148 }
149 } catch (Exception e) {
150 // TODO Auto-generated catch block
151 e.printStackTrace();
152 }
153 finally{
154 if (httpClient!=null) {
155 httpClient.getConnectionManager().shutdown();
156 }
157 }
158 };
159 };
160 thread.start();
161 }
162 }
activity_main.xml
1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 2 xmlns:tools="http://schemas.android.com/tools" 3 android:layout_width="match_parent" 4 android:layout_height="match_parent" 5 tools:context="com.example.day12_01login.MainActivity" 6 android:orientation="vertical" > 7 8 9 <EditText 10 android:id="@+id/et_uername" 11 android:layout_width="fill_parent" 12 android:layout_height="wrap_content" 13 /> 14 <EditText 15 android:id="@+id/et_password" 16 android:layout_width="fill_parent" 17 android:layout_height="wrap_content" 18 /> 19 20 <RelativeLayout 21 android:layout_width="fill_parent" 22 android:layout_height="wrap_content" 23 > 24 <CheckBox 25 android:id="@+id/cb_remeber" 26 android:layout_width="wrap_content" 27 android:layout_height="wrap_content" 28 android:layout_alignParentLeft="true" 29 /> 30 <Button 31 android:id="@+id/bt_login" 32 android:layout_width="wrap_content" 33 android:layout_height="wrap_content" 34 android:layout_alignParentRight="true" 35 android:onClick="login" 36 android:text="get login" 37 /> 38 39 </RelativeLayout> 40 41 <RelativeLayout 42 android:layout_width="fill_parent" 43 android:layout_height="wrap_content" 44 > 45 <CheckBox 46 android:id="@+id/cb_remeber2" 47 android:layout_width="wrap_content" 48 android:layout_height="wrap_content" 49 android:layout_alignParentLeft="true" 50 /> 51 <Button 52 android:id="@+id/bt_login2" 53 android:layout_width="wrap_content" 54 android:layout_height="wrap_content" 55 android:layout_alignParentRight="true" 56 android:onClick="login2" 57 android:text="post login" 58 /> 59 60 </RelativeLayout> 61 62 <Button 63 android:id="@+id/bt_upload" 64 android:layout_width="wrap_content" 65 android:layout_height="wrap_content" 66 android:layout_alignParentRight="true" 67 android:onClick="upload" 68 android:text="uploadfile" 69 /> 70 </LinearLayout>
时间： 2024-08-06 05:29:07