冲刺十五天

实现链接数据库端的朋友信息展示以及Socket通信学习

链接数据库的朋友信息并展示

package com.example.newbsh.UI.friends;

import androidx.lifecycle.ViewModelProviders;

import android.os.Bundle;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;

import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.TextView;

import com.example.newbsh.HttpUtil.HttpUtil;
import com.example.newbsh.MainActivity;
import com.example.newbsh.R;
import com.example.newbsh.UI.friends.list.SideBar;
import com.example.newbsh.UI.friends.list.SortAdapter;
import com.example.newbsh.UI.friends.list.User;

import org.json.JSONArray;
import org.json.JSONException;

import java.util.ArrayList;
import java.util.Collections;

public class FriendFragment extends Fragment {

    private FriendViewModel mViewModel;
    private View view;
    private ListView listView;
    private SideBar sideBar;
    private ArrayList<User> list;
    private Handler handler;
    private String getUsername(){
        return MainActivity.getUserName();
    }
    public static FriendFragment newInstance() {
        return new FriendFragment();
    }
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container,
                             @Nullable Bundle savedInstanceState) {
        view=inflater.inflate(R.layout.friend_fragment, container, false);
        return view;
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        mViewModel = ViewModelProviders.of(this).get(FriendViewModel.class);
        // TODO: Use the ViewModel
        initView();
        getThreadData();
        handler = new Handler(new Handler.Callback() {
            @Override
            public boolean handleMessage(@NonNull Message msg) {     //线程回调更新数据
                if (msg.what == 200)
                {
                    list=new ArrayList<>();
                    JSONArray jsonArray=(JSONArray)msg.obj;
                    for(int i=0;i<jsonArray.length();i++)
                    {
                        try {
                            String friendname= (String) jsonArray.getJSONObject(i).get("friendname");
                            String friendurl= (String) jsonArray.getJSONObject(i).get("friendurl");
                            User bean=new User(friendname,friendurl);
                            list.add(bean);
                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                    Collections.sort(list); // 对list进行排序，需要让User实现Comparable接口重写compareTo方法
                    SortAdapter adapter = new SortAdapter(view.getContext(), list);
                    listView.setAdapter(adapter);
                }
                return true;
            }
        });
    }
    private void initView() {
        listView = (ListView) view.findViewById(R.id.listView);
        sideBar = (SideBar) view.findViewById(R.id.side_bar);
        sideBar.setOnStrSelectCallBack(new SideBar.ISideBarSelectCallBack() {
            @Override
            public void onSelectStr(int index, String selectStr) {
                for (int i = 0; i < list.size(); i++) {
                    if (selectStr.equalsIgnoreCase(list.get(i).getFirstLetter())) {
                        listView.setSelection(i); // 选择到首字母出现的位置
                        return;
                    }
                }
            }
        });
    }
    private void getThreadData() {                     //线程封装网络请求
        new Thread(new Runnable() {
            @Override
            public void run() {
                String reqdata = "";
                String address="http://39.97.181.86/BaiXiaoSheng/myfriend?username="+getUsername();
                try {
                    final JSONArray json = new JSONArray(String.valueOf(HttpUtil.sendPost(address, reqdata)));
                    Log.d("tag", json.toString());
                    Message msg = new Message();
                    msg.what = 200;
                    msg.obj = json;
                    handler.sendMessage(msg);
                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }
}

Socket通信与本地服务器端链接

服务器端：

package servlet;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;
import java.security.Provider;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class Server {

    private static final int PORT=12345;
    private List<Socket> mlist=new ArrayList<>();
    private ServerSocket server=null;
    private ExecutorService myExecutorService=null;
    public static void main(String[] args){
        new Server();
    }
    public Server()
    {
        try {
            server=new ServerSocket(PORT);
            //创建线程池
            myExecutorService=Executors.newCachedThreadPool();
            System.out.println("服务端运行中...
");
            Socket client=null;
            while(true)
            {
                client=server.accept();
                mlist.add(client);
                myExecutorService.execute(new Service(client));
            }
        }catch (Exception e){
            e.printStackTrace();
        }
    }
    class Service implements Runnable
    {
        private Socket socket;
        private BufferedReader in = null;
        private String msg = "";

        public Service(Socket socket) {
            this.socket = socket;
            try
            {
                in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                msg = "用户:" +this.socket.getInetAddress() + "~加入了聊天室"
                        +"当前在线人数:" +mlist.size();
                this.sendmsg();
            }catch(IOException e){e.printStackTrace();}
        }

        @Override
        public void run() {
            try{
                while (true)
                {
                    if((msg=in.readLine())!=null)
                    {
                        if(msg.equals("bye"))
                        {
                            System.out.println("~~~~~~~~~~~");
                            mlist.remove(socket);
                            in.close();
                            msg = "用户:" + socket.getInetAddress()
                                    + "退出:" +"当前在线人数:"+mlist.size();
                            socket.close();
                            this.sendmsg();
                            break;
                        }
                        else
                        {
                            msg=socket.getInetAddress()+"  说："+msg;
                            this.sendmsg();
                        }
                    }
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
        //为连接上服务端的每个客户端发送信息
        public void sendmsg()
        {
            System.out.println(msg);
            int num = mlist.size();
            for(int index = 0;index < num;index++)
            {
                Socket mSocket = mlist.get(index);
                PrintWriter pout = null;
                try {
                    pout = new PrintWriter(new BufferedWriter(
                            new OutputStreamWriter(mSocket.getOutputStream(),"UTF-8")),true);
                    pout.println(msg);
                }catch (IOException e) {e.printStackTrace();}
            }
        }
    }
}

安卓端：

package com.example.sockettest;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.StrictMode;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.Socket;

public class SocketActivity extends AppCompatActivity implements Runnable {

    //定义相关变量,完成初始化
    private TextView txtshow;
    private EditText editsend;
    private Button btnsend;
    private static final String HOST = "192.168.137.1";
    private static final int PORT = 12345;
    private Socket socket = null;
    private BufferedReader in = null;
    private PrintWriter out = null;
    private String content = "";
    private StringBuilder sb = null;

    //定义一个handler对象,用来刷新界面
    public Handler handler = new Handler() {
        public void handleMessage(Message msg) {
            if (msg.what == 0x123) {
                sb.append(content);
                txtshow.setText(sb.toString());
            }
        }
    };


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_socket);
        if (android.os.Build.VERSION.SDK_INT > 9) {
            StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
            StrictMode.setThreadPolicy(policy);
        }

        sb = new StringBuilder();
        txtshow = (TextView) findViewById(R.id.txtshow);
        editsend = (EditText) findViewById(R.id.editsend);
        btnsend = (Button) findViewById(R.id.btnsend1);

        //当程序一开始运行的时候就实例化Socket对象,与服务端进行连接,获取输入输出流
        //因为4.0以后不能再主线程中进行网络操作,所以需要另外开辟一个线程
        new Thread() {
            public void run() {
                try {
                    socket = new Socket(HOST, PORT);
                    in = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF-8"));
                    out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
                            socket.getOutputStream())), true);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }.start();

        new Thread(new Runnable() {
            @Override
            public void run() {
                btnsend.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        String msg = editsend.getText().toString();
                        if (socket.isConnected()) {
                            if (!socket.isOutputShutdown()) {
                                out.println(msg);
                            }
                        }
                    }
                });
            }
        }).start();

        //为发送按钮设置点击事件
        new Thread(SocketActivity.this).start();
    }

    //重写run方法,在该方法中输入流的读取
    @Override
    public void run() {
        try {
            while (true) {
                if (socket.isConnected()) {
                    if (!socket.isInputShutdown()) {
                        if ((content = in.readLine()) != null) {
                            content += "
";
                            handler.sendEmptyMessage(0x123);
                        }
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}