android访问http协议

由于本次笔记是在本机上执行的，所以安装了appache的tomcat服务器，首先认识一下，servlet类，这个类是在tomcat服务器里面进行协议的，tomcat属于协议里面的应用层吧，所以和路由器里面的那层没什么重要的联系，本次是在本机上执行的，因为要进行访问，所以我的手机终端要用到的网管是路由器里面的默认网关，而我的路由器可以发送wifi网络，网关和电脑连接的网关是一致的，所以网络是没有问题的，接下来的问题就是http协议的具体流程了，java里面的tomcat服务器是可以直接加载servlet类的，浏览器可以正常访问，说明servelt的http协议是通的，因为本次用的是post请求数据的，又是传递json数据的，java读取客户端发送过来的消息都是通过流来接受的，所以传递json数据也是通的，接下来就是字符编码的问题了，客户端发送的中文到tomcat这边来默认的不是utf-8，所以servlet在接受客户端发送过来的请求时候需要设置一下接受的字符编码了，这客户端发送的请求已经接收了，现在就是要给客户端发送数据了，不知道什么问题，反正一开始我客户端接受的数据不论怎么解码，编码都是乱码，最终确认了让tomcat默认发送消息头是默认的编码，然后客户端这边用tomcat默认的字符编码解码，然后再编码，乱码问题解决了；现在来看看截图

1.查看本地网络配置

服务端的代码:

package com.android.test;import java.io.IOException;import java.io.InputStream;import java.io.UnsupportedEncodingException;import java.util.Collection;import java.util.Date;import java.util.Enumeration;import javax.servlet.ServletException;import javax.servlet.annotation.WebInitParam;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.json.JSONException;import org.json.JSONObject;import netscape.javascript.JSObject;/** * Servlet implementation class AndroidServlet */@WebServlet(urlPatterns = "/Login", name = "AndroidServlet", initParams = {@WebInitParam(name = "name", value = "huangxudong"), @WebInitParam(name = "pass", value = "123456") })public class AndroidServlet extends HttpServlet {private static final long serialVersionUID = 1L;/** * @see HttpServlet#HttpServlet() */public AndroidServlet() {super();// TODO Auto-generated constructor stub}/** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse *      response) */protected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {// TODO Auto-generated method stub}/** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse *      response) */protected void doPost(HttpServletRequest request, HttpServletResponse response){// TODO Auto-generated method stubString nString=response.getContentType();StringBuffer stringBuffer = new StringBuffer();String name = null;String pass = null;InputStream inputStream = null;try {request.setCharacterEncoding("UTF-8");} catch (UnsupportedEncodingException e2) {// TODO Auto-generated catch blocke2.printStackTrace();}try {inputStream = request.getInputStream();} catch (IOException e1) {// TODO Auto-generated catch blocke1.printStackTrace();}byte[] bs = new byte[1024];int length;try {while ((length = inputStream.read(bs)) != -1) {stringBuffer.append(new String(bs, 0, length,"UTF-8"));}} catch (IOException e1) {// TODO Auto-generated catch blocke1.printStackTrace();}if (stringBuffer != null) {JSONObject jsonObject = new JSONObject(stringBuffer);try {name = jsonObject.getString("username");pass = jsonObject.getString("password");} catch (JSONException e) {// TODO Auto-generated catch blocke.printStackTrace();}}if (name != null && pass != null) {if (name.equals(getInitParameter("name")) && pass.equals(getInitParameter("pass"))) {JSONObject jsonObject = new JSONObject();try {jsonObject.put("msg", "112");jsonObject.put("date", new Date());response.setContentType("application/json");response.setCharacterEncoding("UTF-8");response.getWriter().write(new String(jsonObject.toString().getBytes(),"UTF-8"));} catch (JSONException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}} else {JSONObject jsonObject = new JSONObject();try {jsonObject.put("msg", "123啊是");jsonObject.put("date", new Date());response.getWriter().write(jsonObject.toString());} catch (JSONException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}

由于是进行测试，所以代码质量没有在意．．

再来看ａｎｄｒｏｉｄ端的代码：

package www.hubei.servlet.myapplication;import android.support.design.widget.TextInputEditText;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.text.TextUtils;import android.util.Log;import android.view.View;import android.widget.AdapterView;import android.widget.Button;import android.widget.EditText;import android.widget.Toast;import org.json.JSONException;import org.json.JSONObject;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStream;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.net.URLDecoder;public class MainActivity extends AppCompatActivity implements View.OnClickListener{    private TextInputEditText mTextInputEditText,mTextInputEditText1;    private Button mButton,mButton1;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mTextInputEditText= (TextInputEditText) findViewById(R.id.et_username);        mTextInputEditText1= (TextInputEditText) findViewById(R.id.et_userpass);        mButton= (Button) findViewById(R.id.btn_get);        mButton1= (Button) findViewById(R.id.btn_post);        mButton.setOnClickListener(this);        mButton1.setOnClickListener(this);    }    private void doPost(String username,String password) throws IOException, JSONException {        if (mTextInputEditText.getText().toString().isEmpty()||mTextInputEditText.getText().toString().equals(null)){            Toast.makeText(this, "用户名不能为空!!!", Toast.LENGTH_SHORT).show();            return;        }        if (mTextInputEditText1.getText().toString().isEmpty()||mTextInputEditText1.getText().toString().equals(null)){            Toast.makeText(this, "用户名密码不能为空!!!", Toast.LENGTH_SHORT).show();            return;        }        URL url=new URL("http://10.0.2.2:8080/TestHttp/Login");        HttpURLConnection httpURLConnection= (HttpURLConnection) url.openConnection();        httpURLConnection.setDoOutput(true);        httpURLConnection.setDoInput(true);        httpURLConnection.setRequestMethod("POST");        httpURLConnection.setConnectTimeout(4000);        httpURLConnection.setRequestProperty("Content-Type", "application/json");        httpURLConnection.setRequestProperty("Connection", "Keep-Alive");        httpURLConnection.setRequestProperty("Charset", "UTF-8");        OutputStream outputStream=httpURLConnection.getOutputStream();        JSONObject jsonObject=new JSONObject();        jsonObject.put("username",username);        jsonObject.put("password",password);        String url1=new String(jsonObject.toString().getBytes(),"UTF-8");        StringBuffer stringBuffer=new StringBuffer();        outputStream.write(url1.getBytes());        outputStream.flush();        if (200==httpURLConnection.getResponseCode()){            InputStream inputStream=httpURLConnection.getInputStream();            InputStreamReader streamReader=new InputStreamReader(inputStream,"iso8859-1");            char []bytes=new char[1024];            int length;            while ((length=streamReader.read(bytes))!=-1){                stringBuffer.append(new String(bytes,0,length));            }        }        Log.e("aaa", new String(stringBuffer.toString().getBytes("iso8859-1"),"UTF-8"));    }    @Override    public void onClick(View view) {        switch (view.getId()){            case R.id.btn_get:                break;            case R.id.btn_post:                new Thread(){                    @Override                    public void run() {                        super.run();                        try {                            doPost(mTextInputEditText.getText().toString(),mTextInputEditText1.getText().toString());                        } catch (IOException e) {                            e.printStackTrace();                        } catch (JSONException e) {                            e.printStackTrace();                        }                    }                }.start();                break;        }    }}

由于最后我要在模拟器上进行测试，所以主机地址改成了ａｎｄｒｏｉｄ模拟器默认的ｉｐ地址，这都是要注意的哦。

最后还说下，用谷歌浏览器的开发者工具，可以对ｗｅｂ前端进行抓包，然后进行分析，协议分：协议头和ｂｏｄｙ体的，客户端发送ｈｔｔｐ协议请求都是要设置协议头的，服务器返回的时候也是要设置协议头的，具体的协议头可以在开发者工具中查看，顺便截图一下谷歌的开发者工具：