get方式和post方式的区别：
1.请求的URL地址不同：
post："http://xx:8081//servlet/LoginServlet" get：http://xxx:8081//servlet/LoginServlet?username=root&pwd=1232.请求头不同：
****post方式多了几个请求头：Content-Length , Cache-Control , OriginopenConnection.setRequestProperty("Content-Length", body.length()+"");
openConnection.setRequestProperty("Cache-Control", "max-age=0"); openConnection.setRequestProperty("Origin", "http://xx:8081");****post方式还多了请求的内容：username=root&pwd=123
//设置UrlConnection可以写请求的内容
openConnection.setDoOutput(true); //获取一个outputstream，并将内容写入该流 openConnection.getOutputStream().write(body.getBytes());3.请求时携带的内容大小不同
get:1k post:理论无限制
登录的布局文件
登录的Activity代码
public class GetPostActivity extends AppCompatActivity { private EditText et_username; private EditText et_password; private CheckBox cb_rem; private Button bt_login; private Context mcontext; private String username; private String password; private boolean isRem; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_get_post); et_username = (EditText) findViewById(R.id.input_username); et_password = (EditText) findViewById(R.id.input_password); cb_rem = (CheckBox) findViewById(R.id.cb_rem); bt_login = (Button) findViewById(R.id.bt_login); bt_login.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { login(); } }); } //创建一个handler Handler handler = new Handler() { @Override public void handleMessage(Message msg) { boolean isloginsuccess = (boolean) msg.obj; if (isloginsuccess) { //判断是否记住密码,要保存到本地，封装成方法 if (isRem) { //保存用户名和密码 boolean result = UserInfoUtil.saveUserInfo(mcontext, username, password); if (result) { Toast.makeText(getApplicationContext(), "用户名和密码保存成功", Toast.LENGTH_SHORT).show(); } else { Toast.makeText(getApplicationContext(), "用户名和密码保存失败", Toast.LENGTH_SHORT).show(); } } else { Toast.makeText(getApplicationContext(), "登录成功", Toast.LENGTH_SHORT).show(); } } else { Toast.makeText(getApplicationContext(), "登录失败", Toast.LENGTH_SHORT).show(); } } }; public void login() { username = et_username.getText().toString().trim(); password = et_password.getText().toString().trim(); isRem = cb_rem.isChecked(); //判断是否密码或者用户名为空 if (TextUtils.isEmpty(username) || TextUtils.isEmpty(password)) { Toast.makeText(this, "用户名和密码不能为空", Toast.LENGTH_SHORT).show(); return; } //post方法登录是否成功 LoginHttpUtil.requestNetForGetLogin(handler, username, password); }}
新建一个Net包，处理网络请求的操作，新建一个loginhttputil.java
public class LoginHttpUtil { //get方式登录 public static void requestNetForGetLogin(final Handler handler,final String username,final String password) { //在子线程中操作网络请求 new Thread(new Runnable() { @Override public void run() { //urlConnection请求服务器，验证 try { //1：url对象 URL url = new URL("http://192.168.1.100:8081//servlet/LoginServlet?username=" + URLEncoder.encode(username)+ "&pwd=" + URLEncoder.encode(password) + ""); //2;url.openconnection HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //3 conn.setRequestMethod("GET"); conn.setConnectTimeout(10 * 1000); //4 int code = conn.getResponseCode(); if (code == 200) { InputStream inputStream = conn.getInputStream(); String result = StreamUtil.stremToString(inputStream); System.out.println("=====================服务器返回的信息：：" + result); boolean isLoginsuccess=false; if (result.contains("success")) { isLoginsuccess=true; } Message msg = Message.obtain(); msg.obj=isLoginsuccess; handler.sendMessage(msg); } } catch (Exception e) { e.printStackTrace(); } } }).start(); } //post方式登录 public static void requestNetForPOSTLogin(final Handler handler,final String username,final String password) { new Thread(new Runnable() { @Override public void run() { //urlConnection请求服务器，验证 try { //1：url对象 URL url = new URL("http://192.168.1.100:8081//servlet/LoginServlet"); //2;url.openconnection HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //3设置请求参数 conn.setRequestMethod("POST"); conn.setConnectTimeout(10 * 1000); //请求头的信息 String body = "username=" + URLEncoder.encode(username) + "&pwd=" + URLEncoder.encode(password); conn.setRequestProperty("Content-Length", String.valueOf(body.length())); conn.setRequestProperty("Cache-Control", "max-age=0"); conn.setRequestProperty("Origin", "http://192.168.1.100:8081"); //设置conn可以写请求的内容 conn.setDoOutput(true); conn.getOutputStream().write(body.getBytes()); //4响应码 int code = conn.getResponseCode(); if (code == 200) { InputStream inputStream = conn.getInputStream(); String result = StreamUtil.stremToString(inputStream); System.out.println("=====================服务器返回的信息：：" + result); boolean isLoginsuccess=false; if (result.contains("success")) { isLoginsuccess=true; } Message msg = Message.obtain(); msg.obj=isLoginsuccess; handler.sendMessage(msg); } } catch (Exception e) { e.printStackTrace(); } } }).start(); } }
二：get方式提交数据时候出现乱码的情况l;解决办法如下：
一般在开发客户端和服务端的编码要保持一致。
android端的默认编码是utf-8;
做url请求时需要对参数进行URLEncode编码.
URL url = new URL("http://xx:8081/servlet/LoginServlet?username="+URLEncoder.encode(username)+"&pwd="+URLEncoder.encode(password))
# 2. post方式提交数据乱码解决
String body = "username=" + URLEncoder.encode(username) + "&pwd=" + URLEncoder.encode(password);