《安卓网络编程》之第七篇 java编写Service程序

  1 import java.io.*;
  2 import java.awt.*;
  3 import java.awt.event.*;
  4 import javax.swing.*;
  5 import java.net.*;
  6 import java.util.*;
  7
  8 class Conn extends Thread{
  9     private JTextArea txt;
 10     private Socket st;
 11     private String msg = null;
 12     private BufferedReader br = null;
 13     private PrintStream ps;
 14     public Conn(Socket st,JTextArea txt){
 15         this.st = st;
 16         this.txt = txt;
 17         start();
 18     }
 19     public void run(){
 20         try{
 21             br = new BufferedReader(new InputStreamReader(st.getInputStream()));
 22             ps = new PrintStream(new DataOutputStream(st.getOutputStream()));
 23         }catch(Exception e){
 24             System.err.println("input failed");
 25         }
 26         while(true){
 27             try{
 28                 msg = br.readLine();//阻塞方法
 29                 txt.append("从客户端收到信息:"+msg+‘\n‘);
 30                 txt.append("信息接受时间是:"+new Date()+"\n");
 31                 //创建读取文件线程，并将读取到的内容通过服务器发送出去
 32                 FileThread ft = new FileThread();
 33                 Thread t = new Thread(ft);
 34                 t.start();
 35                 while(ft.flag);
 36                 System.out.println(ft.readData);
 37                 Server.send(ft.readData);
 38
 39             }catch(Exception e){
 40                 System.err.println("connection closed");
 41                 break;
 42             }
 43         }
 44     }
 45     public void send(String msg){
 46       ps.println(msg);
 47     }
 48
 49 }
 50
 51
 52 class FileThread implements Runnable{
 53     public String readData = "";
 54     public static boolean flag = true;
 55     public void run() {
 56         readData = readFileByLines("D:\\Hello.txt");
 57         flag = false;
 58         System.out.println(readData);
 59     }
 60
 61     /**
 62      * 以行为单位读取文件，常用于读面向行的格式化文件
 63      */
 64     public String readFileByLines(String fileName) {
 65         File file = new File(fileName);
 66         BufferedReader reader = null;
 67         String tempString = null;
 68         String readData = "";
 69         try {
 70             System.out.println("以行为单位读取文件内容，一次读一整行：");
 71             reader = new BufferedReader(new FileReader(file));
 72             int line = 1;
 73
 74             // 一次读入一行，直到读入null为文件结束
 75             while ((tempString = reader.readLine()) != null) {
 76                 // 显示行号
 77 //                System.out.println("line " + line + ": " + tempString);
 78 //                line++;
 79                 readData = readData.concat(tempString);//字符串拼接推荐函数
 80             }
 81             reader.close();
 82         } catch (IOException e) {
 83             e.printStackTrace();
 84         } finally {
 85             if (reader != null) {
 86                 try {
 87                     reader.close();
 88                 } catch (IOException e1) {
 89                 }
 90             }
 91         }
 92
 93         return  readData;
 94     }
 95
 96 }
 97
 98
 99 public class Server extends JFrame{
100     private JTextArea txt;
101     private ServerSocket ss;
102     public String tempString = null;
103     private static java.util.List<Conn> conns = new ArrayList<Conn>();
104     public Server(){
105        txt = new JTextArea();
106        this.setTitle("服务器");
107        this.setLayout(new BorderLayout());
108        this.add(new JScrollPane(txt),BorderLayout.CENTER);
109        this.setSize(500,300);
110        this.setVisible(true);
111
112        run();
113     }
114     public void run(){
115         try{
116             ss = new ServerSocket(3000);
117         }catch(Exception e){
118             System.err.println("open socket failed");
119         }
120         txt.append("服务器已经启动！"+"\n");
121         while(true){
122             try{
123                 Socket st=ss.accept();
124                 conns.add(new Conn(st,txt));
125             }
126             catch(IOException ex){
127                 System.err.println(ex);
128             }
129         }
130     }
131     public static void send(String msg){
132       for(Conn c:conns)
133         c.send(msg);
134     }
135
136     public static void main(String args[]){
137
138         Server myserver=new Server();
139      }
140
141 }

另外一种写法：