安卓socket实例(二)实现文件列表动态访问

49 阅读3分钟

安卓socket实例(二)实现文件列表动态访问,访问文件夹之后通过listview展示,并在点击文件夹后进入文件夹,获得其内容。

安卓Socket2.gif

idea服务端更新

image.png

为了防止代码量上升可能带来的结构杂乱,我们对服务端架构进行优化,server包负责socket服务基础实现,data包负责处理各种安卓端的命令。

将readSocketMsg,writeBackMsg方法单独拿出,创建一个SocketMsg方法类,专门负责数据流的读取与写入。

SocketMsg.java

package lrz.server;

import java.io.*; import java.net.Socket; import java.util.ArrayList;

public class SocketMsg {

public static ArrayList readSocketMsg(Socket socket) throws IOException { ArrayList msgList=new ArrayList(); InputStream inputStream = socket.getInputStream(); InputStreamReader reader = new InputStreamReader(inputStream, "utf-8"); BufferedReader bufferedReader=new BufferedReader(reader); String lineNumStr = bufferedReader.readLine(); int lineNum=Integer.parseInt(lineNumStr); for(int i=0;i<lineNum;i++){ String str = bufferedReader.readLine(); msgList.add(str); } //读取结束后,输入流不能关闭,此时关闭,会将socket关闭,从而导致后续对socket写操作无法实现 return msgList; }

public static void writeBackMsg(Socket socket, ArrayList msgBackList) throws IOException { BufferedOutputStream os = new BufferedOutputStream(socket.getOutputStream()); OutputStreamWriter writer=new OutputStreamWriter(os,"UTF-8"); writer.write(""+msgBackList.size()+"\n"); //未真正写入的输出流,仅仅在内存中 writer.flush(); //写入输出流,真正将数据传输出去 for(int i=0;i<msgBackList.size();i++){ writer.write(msgBackList.get(i)+"\n"); writer.flush(); }

}

}

创建NetFileData.java作为文件夹访问的方法类,将exeDir()方法放入其中。

NetFileData.java

package lrz.data;

import java.io.File; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Date;

public class NetFileData {

public static ArrayList exeDir(String cmdBody) throws Exception { // TODO Auto-generated method stub ArrayList backList=new ArrayList();

File file = new File(cmdBody); File[] listFiles = file.listFiles(); for(File mfile:listFiles){ String fileName = mfile.getName(); long lastModified = mfile.lastModified();//获取文件修改时间 SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//给时间格式,例如:2018-03-16 09:50:23 String fileDate = dateFormat.format(new Date(lastModified));//取得文件最后修改时间,并按格式转为字符串 String fileSize="0"; String isDir="1"; if(!mfile.isDirectory()){//判断是否为目录 isDir="0"; fileSize=""+mfile.length(); } backList.add(fileName+">"+fileDate+">"+fileSize+">"+isDir+">"); } return backList; } }

ServerSocket01.java主函数则将以上方法移除,改为调用

package lrz.server;

import lrz.data.NetFileData;

import java.io.*; import java.net.InetAddress; import java.net.NetworkInterface; import java.net.ServerSocket; import java.net.Socket; import java.util.ArrayList; import java.util.Enumeration;

public class ServerSocket01 { int port = 8019;// 自定义一个端口,端口号尽可能挑选一些不被其他服务占用的端口,祥见blog.csdn.net/hsj521li/ar… static int connect_count = 0;// 连接次数统计 ArrayList msgBackList;

public ServerSocket01() { // TODO Auto-generated constructor stub }

public ServerSocket01(int port) { super(); this.port = port; }

private void printLocalIp(ServerSocket serverSocket) {// 枚举打印服务端的IP try { System.out.println("服务端命令端口prot=" + serverSocket.getLocalPort()); Enumeration interfaces = null; interfaces = NetworkInterface.getNetworkInterfaces(); while (interfaces.hasMoreElements()) { NetworkInterface ni = interfaces.nextElement(); Enumeration addresss = ni.getInetAddresses(); while (addresss.hasMoreElements()) { InetAddress nextElement = addresss.nextElement(); String hostAddress = nextElement.getHostAddress(); System.out.println("本机IP地址为:" + hostAddress); } } } catch (Exception e) { e.printStackTrace(); } }

public void work() throws IOException { // 注意:由于Socket的工作是阻塞式,Android端Socket的工作必须在新的线程中实现,若在UI主线程中工作会报错

ServerSocket serverSocket = new ServerSocket(port); printLocalIp(serverSocket); while (true) {// 无限循环,使之能结束当前socket服务后,准备下一次socket服务

System.out.println("Waiting client to connect....."); Socket socket = serverSocket.accept();// 阻塞式,直到有客户端连接进来,才会继续往下执行,否则一直停留在此代码 System.out.println("Client connected from: "

  • socket.getRemoteSocketAddress().toString());

ArrayList cmdList= SocketMsg.readSocketMsg(socket); cmdList.forEach(s -> System.out.println(s));

String cmdbody=cmdList.get(0); try { msgBackList= NetFileData.exeDir(cmdbody); } catch (Exception e) { e.printStackTrace(); } msgBackList.forEach(s -> System.out.println(s)); SocketMsg.writeBackMsg(socket,msgBackList); socket.close(); System.out.println("当前Socket服务结束");

} }

/**

  • @param args */ public static void main(String[] args) { // TODO Auto-generated method stub try { new ServerSocket01().work(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); }

}

}

安卓端更新

使用listview显示文件夹内容,并且实现动态访问。

MainActivity.java更新了简单的listview显示,设立互动事件,在点击某个列表部分时向服务端发动指定命令,返回结果后更新列表,实现互动效果。

package com.example.android_app;

import androidx.appcompat.app.AppCompatActivity; import android.os.Bundle; import androidx.annotation.NonNull; import android.os.Build; import android.os.Handler; import android.os.Message; import android.view.View; import android.widget.AdapterView; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.EditText; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

public static final String KEY_SERVER_ACK_MSG = "KEY_SERVER_ACK_MSG"; private Handler handler = null; EditText url,way,dir; ListView lv; Button submit; SocketClient socketClient=null; String here; ArrayList data; int port; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main);

url=findViewById(R.id.url); way=findViewById(R.id.way); dir=findViewById(R.id.dir); lv=findViewById(R.id.listview); submit=findViewById(R.id.submit);

handler=new Handler(new Handler.Callback() { @Override public boolean handleMessage(@NonNull Message msg) {

Bundle data_bundle = msg.getData(); data=data_bundle.getStringArrayList(KEY_SERVER_ACK_MSG);

data=dataMaker(); printAdapter(data);

return false; } });

submit.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { port=Integer.parseInt(way.getText().toString()); here=dir.getText().toString(); getdata(); } });

lv.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { here=here+"/"+data.get(position); getdata(); } }); }

private void getdata() { socketClient=new SocketClient(url.getText().toString(),port,handler); socketClient.work(here); }

private ArrayList dataMaker() { ArrayList dataResult=new ArrayList<>(); int i=data.size(); for (int j = 0; j <i ; j++) { String str=data.get(j); str=str.substring(0,str.indexOf(">"));

一个人可以走的很快,但一群人才能走的更远!不论你是正从事IT行业的老鸟或是对IT行业感兴趣的新人,都欢迎加入我们的社区(技术交流、学习资源、职场吐槽、大厂内推、面试辅导),让我们一起学习成长!