消费者与生产者问题 生产者与消费者问题,听说是讲线程的一个经典问题.简单来说,有生产者,消费者,生产者不断的生产消费者不断的消费.要用代码模拟这一过程. 建立了5个类 Productor(生产者) Consumer(消费者) Warehouse(仓库) Something(物品) ProductorAndConsumer(main()函数所在类) 本代码从最基本的实现开始逐步完善，修改N次，多个产品多个仓库也是可以的.只不过,和我曾想象的实现不太一样. 喜欢研究的朋友自己做测试吧. 部分代码已经修改 用蓝字标出2009.12.12 package test; /* 生产者消费者问题--消费者 * @author yeS * @version 1.0.0 */ public class Consumer implements Runnable { /* * 消费地点: w仓库 * 消费物品: s * 一次消费数量: num * 计划消费总数: total */ private Warehouse w; private Something s; private int num; private int total; // 构造函数 Consumer(Warehouse w, Something s, int num, int total) { this.w = w; this.s = s; this.num = num; this.total = total; } /* * 开始消费 * * 等待生产 1)仓库内有物品 -> A)消费计划未完成 -> 消费 -> 输出消费信息 -> 1) * -> B)消费计划完成 -> 结束 -> 2) * 2)仓库内没有物品 -> 结束 */ public void run() { // 记录消费次数 int count = 0; while(total != (count*num)) { w.takeOut(s, num); count++; System.out.println("第" + count + "次消费----Consumer : 我从第" + w.getID() + "号仓库,拿了" + num + "个" + s.getName()); } } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ package test; /* 生产者消费者问题--生产者 * @author yeS * @version 1.0.0 */ public class Productor implements Runnable { /* * 生产者要生产的物品 s * 生产的时间，即次数 t * 每次生产的物品数量 num * 存放物品的仓库 w */ private Something s; private int t; private int num; private Warehouse w; private boolean ProductorInfo = false; // 构造函数 Productor(Something s, int t, int num, Warehouse w) { this.s = s; this.t = t; this.num = num; this.w = w; } /* * 开始生产 * * 生产过程： 1)生产出物品 -> 放到仓库里 -> 通知我的生产信息 -> A)达到要求的供货数量 -> 停止生产 * B)没有达到要求供货数量 -> 1) */ public void run() { for (int i = 0; i < t; i++) { s.setNumber(num); w.add(s); System.out.println("第" + (i+1) + "次生产----" + "Productor : 我生产了" + num + "个" + s.getName() + ",放在了" + w.getID() + "号仓库中"); if (i == (t-1)) { ProductorInfo = true; System.out.println("供货结束----我总共生产了" + 10 * num + "个" + s.getName()); } } } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ package test; /* 生产者消费者问题--仓库 * @author yeS * @version 1.0.0 */ public class Warehouse { /* * 仓库号 id * 仓库的容量 capacity * 仓库总物品的数量 total */ private int id; private int capacity; private int total; //仓库的构造函数 Warehouse(int id, int capacity) { this.id = id; this.capacity = capacity; } /* * 这里wait()的使用，需要满足几个条件 * 1,包含wait()的代码必须锁定，应锁定在判断句外，锁定代码和方法均可, * 2,必须使用notifyAll()或者是notify(),推荐使用notifyAll(). * * 网上说： wait() 是使持有对象锁的线程释放锁; wait(long) 是使持有对象锁的线程释放锁时间为long(毫秒)后,再次获得锁,wait()和wait(0)等价; notify() 是唤醒一个正在等待该对象锁的线程,如果等待的线程不止一个,那么被唤醒的线程由jvm确定; notifyAll 是唤醒所有正在等待该对象锁的线程. 并且应该优先使用notifyAll()方法,因为唤醒所有线程比唤醒一个线程更容易让jvm找到最适合被唤醒的线程 . 对于上述方法,只有在当前线程中才能使用,否则报运行时错误 */ //向仓库添加物品 synchronized void add(Something s) { int sum = total + s.getNumber(); if (total == capacity || sum > capacity) { System.out.println("仓库物品已满，请等待"); try { wait(); } catch (InterruptedException e) { e.printStackTrace(); } } total = total + s.getNumber(); this.notifyAll(); } //从仓库拿出物品,数量为num synchronized void takeOut(Something s, int num) { if(total < num) { System.out.println("仓库物品不足清等待"); try { this.wait(); } catch (InterruptedException e) { e.printStackTrace(); } } total = total - num; this.notifyAll(); } /* * 获得仓库的相关信息 */ int getID() { return id; } int getTotal() { return total; } int getCapa city() { return capacity; } void setTotal(int t) { this.total = t; } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ package test; /* 生产者消费者问题--物品 * @author yeS * @version 1.0.0 */ public class Something { /* * 物品的名字 * 物品的数量 */ private String name; private int number; //物品的无参构造函数(2009.12.12修改) Something(String n) { number = 0; name = n; } //修改物品数量 void setNumber(int num) { number = num; } /* * 获得物品信息 */ int getNumber() { return number; } String getNa me() { return name; } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ //(2009.12.12修改) package test1; /* 生产者消费者问题 * @author yeS * @version 1.0.0 */ public class ProductorAndConsumer { public static void main(String[] args) { Warehouse w = new Warehouse(1,20); Something s1 = new Something("西瓜"); Something s2 = new Something("苹果"); Productor p1 = new Productor(s1, 5, 3, w); Productor p2 = new Productor(s2, 5, 3, w); Consumer c1 = new Consumer(w, s1, 1, 15); Consumer c2 = new Consumer(w,s2,1,15); Thread t1 = new Thread(p1); Thread t2 = new Thread(p2); Thread t3 = new Thread(c1); Thread t4 = new Thread(c2); t1.start(); t2.start(); t3.start(); t4.start(); } } ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 编写多线程Web 服务器 会编写单线程,多线程就不是问题.只需要注意哪段是要同步运行的代码即可 package ThreadedServer; /* 多线程的http1.0服务器 * @author yeS * @version 1.0.0 */ import java.io.*; import java.net.*; import java.util.*; public class ThreadedServer { public static final int PORT_3490 = 8000; public static String DEFAULTPATH_3490 = "c:/www/"; public static void main(String[] args) { //启动服务器 try { ServerSocket serverSocket_3490 = new ServerSocket(PORT_3490); System.out.println("*****************************"); System.out.println(" *****夜觞服务器已经启动***** "); System.out.println(" ****服务器端口号: " + PORT_3490 + "**** "); System.out.println("****************************"); while(true) { //建立连接 Socket clientSocket_3490 = serverSocket_3490.accept(); Server server = new Server(clientSocket_3490,DEFAULTPATH_3490); Thread thread = new Thread(server); thread.start(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } class Server implements Runnable { private Socket clientSocket_3490; private String DEFAULTPATH_3490; Server(Socket socket_3490, String defaultPath_3490) { clientSocket_3490 = socket_3490; DEFAULTPATH_3490 = defaultPath_3490; } public void run() { try { //声明从客户端读取数据要用的流 BufferedReader rFromClient_3490 = new BufferedReader( new InputStreamReader(clientSocket_3490.getInputStream())); //声明从服务器发送数据到客户端要用的流 DataOutputStream wToClient_3490 = new DataOutputStream(clientSocket_3490.getOutputStream()); PrintStream pToClient_3490 = new PrintStream(clientSocket_3490.getOutputStream()); //将从客户端读取的数据的一行赋值给messageFromClient_3490 String messageFromClient_3490 = rFromClient_3490.readLine(); /* * 处理从客户端读取的消息 */ StringTokenizer token_3490 = new StringTokenizer(messageFromClient_3490); System.out.println("客户端发送的请求报文:" + messageFromClient_3490); // 读取客户端发送过来的请求报文头部信息 while((messageFromClient_3490 = rFromClient_3490.readLine()) != null) { System.out.println(messageFromClient_3490); if(messageFromClient_3490.equals("")) break; } //处理get请求 if(token_3490.nextToken().equalsIgnoreCase("get")) { //获得文件路径 String filePath_3490 = token_3490.nextToken(); if(filePath_3490.startsWith("/") == true) { filePath_3490 = DEFAULTPATH_3490 + filePath_3490.substring(1); } else { System.out.println("请输入正确的命令(get /文件名)"); return ; } //将文件的内容写入字节数组中 File file_3490 = new File(filePath_3490); int fileLength_3490 = (int)file_3490.length(); byte[] bufForFile_3490 = new byte[fileLength_3490]; FileInputStream rFromFile_3490 = new FileInputStream(filePath_3490); rFromFile_3490.read(bufForFile_3490); /* * 发送数据到客户端 */ //响应报文格式 wToClient_3490.writeBytes("HTTP/1.0 200 OK\n"); wToClient_3490.writeBytes("Date: " + new Date().toGMTString() + "\n"); wToClient_3490.wri teBytes("Server: yeS Server/1.0.0\n"); wToClient_3490.writeBytes("Content-Length: " + fileLength_3490 + "\n"); if(filePath_3490.endsWith(".html")||filePath_3490.endsWith(".htm")) wToClient_3490.writeBytes("Conten-Type: text/html\r\n"); if(filePath_3490.endsWith(".jsp")) wToClient_3490.writeBytes("Conten-Type: text/jsp\r\n"); if(filePath_3490.endsWith(".jpg")) wToClient_3490.writeBytes("Conten-Type: image/jpg\r\n"); if(filePath_3490.endsWith(".gif")) wToClient_3490.writeBytes("Conten-Type: image/gif\r\n"); wToClient_3490.writeBytes("\r\n"); wToClient_3490.flush(); //向客户端传送文件 pToClient_3490.write(bufForFile_3490, 0, bufForFile_3490.length); pToClient_3490.flush(); pToClient_3490.close(); clientSocket_3490.close(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } 简单的HTTP 1.0 客户端/服务器程序 基本实现,但是客户端只能保存小于16k的图片,不知道为什么.有会的请告诉我下,谢谢.我自己也会继续探求解决之法的. ~~~~~~~~~~~~~~~~~~~服务器~~~~~~~~~~~~~~~~~~~~~~~~~~~ package http; /* http1.0服务器 * @author yeS * @version 1.0.0 */ import java.io.*; import java.net.*; import java.util.*; public class Server { public static final int PORT_3490 = 8000; public static String DEFAULTPATH_3490 = "c:/www/"; @SuppressWarnings("deprecation") public static void main(String[] args) { try { //启动服务器 ServerSocket serverSocket_3490 = new ServerSocket(PORT_3490); System.out.println("*****************************"); System.out.println(" *****夜觞服务器已经启动***** "); System.out.println(" ****服务器端口号: " + PORT_3490 + "**** "); System.out.println("****************************"); while(true) { //建立连接 Socket clientSocket_3490 = serverSocket_3490.accept(); //声明从客户端读取数据要用的流 BufferedReader rFromClient_3490 = new BufferedReader( new InputStreamReader(clientSocket_3490.getInputStream())); //声明从服务器发送数据到客户端要用的流 DataOutputStream wToClient_3490 = new DataOutputStream(clientSocket_3490.getOutputStream()); PrintStream pToClient_3490 = new PrintStream(clientSocket_3490.getOutputStream()); //将从客户端读取的数据的一行赋值给messageFromClient_3490 String messageFromClient_3490 = rFromClient_3490.readLine(); /* * 处理从客户端发送过来的请求报文 */ StringTokenizer token_3490 = new StringTokenizer(messageFromClient_3490); System.out.println("客户端发送的请求报文:" + messageFromClient_3490); // 读取客户端发送过来的请求报文头部信息 System.out.println(messageFromClient_3490); //处理get请求 if(token_3490.nextToken().equalsIgnoreCase("get")) { //获得文件路径 String filePath_3490 = token_3490.nextToken(); if(filePath_3490.startsWith("/") == true) { filePath_3490 = DEFAULTPATH_3490 + filePath_3490.substring(1); } //将文件的内容写入字节数组中 File file_3490 = new File(filePath_3490); int fileLength_3490 = (int)file_3490.length(); byte[] bufForFile_3490 = new byte[fileLength_3490]; FileInputStream rFromFile_3490 = new FileInputStream(filePath_3490); rFromFile_3490.read(bufForFile_3490); /* * 发送数据到客户端 */ //响应报文格式 wToClient_3490.writeBytes("HTTP/1.0 200 OK\n"); wToClient_3490.writeBytes("Date: " + new Date().toGMTString() + "\n"); wToClient_3490.writeBytes("Server: yeS Server/ 1.0.0\n"); wToClient_3490.writeBytes("Content-Length: " + fileLength_3490 + "\n"); if(filePath_3490.endsWith(".html")||filePath_3490.endsWith(".htm")) wToClient_3490.writeBytes("Conten-Type: text/html\r\n"); if(filePath_3490.endsWith(".jsp")) wToClient_3490.writeBytes("Conten-Type: text/jsp\r\n"); if(filePath_3490.endsWith(".jpg")) wToClient_3490.writeBytes("Conten-Type: image/jpg\r\n"); if(filePath_3490.endsWith(".gif")) wToClient_3490.writeBytes("Conten-Type: image/gif\r\n"); wToClient_3490.writeBytes("\r\n"); wToClient_3490.flush(); //向客户端传送文件 pToClient_3490.write(bufForFile_3490, 0, bufForFile_3490.length); pToClient_3490.flush(); pToClient_3490.close(); clientSocket_3490.close(); } } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } ~~~~~~~~~~~~~~~~~~~~~客户端~~~~~~~~~~~~~~~~~~~~~~~~ package http; /* http1.0客户端 * @author yeS * @version 1.0.0 */ import java.io.*; import java.net.*; public class Client { public static final String HOST_3490 = "localhost"; public static final int SERVERPORT_3490 = 8000; public static void main(String[] args) { try { //和服务器建立连接 Socket clientSocket_3490 = new Socket(HOST_3490,SERVERPORT_3490); System.out.println("与服务器的连接已经建立"); System.out.println("请输入您要向服务端发送的请求"); System.out.println("(请求格式: GET /文件名. ps: 默认路径是C:/www/； 或者GET 文件全路径)"); //声明传送和接收数据用到的流 BufferedReader rFromIn_3490 = new BufferedReader( new InputStreamReader(System.in)); InputStream rFromServer_3490 = new BufferedInputStream(clientSocket_3490.getInputStream()); /* * 将命令发送给服务器 */ PrintStream wToServer_3490 = new PrintStream(clientSocket_3490.getOutputStream()); String messageFronIn_3490 = rFromIn_3490.readLine(); wToServer_3490.println(messageFronIn_3490); /* * 读取服务器响应的信息 */ boolean isHead_3490 = false; String headMessage_3490 = ""; int messageFromServer_3490 = rFromServer_3490.read(); headMessage_3490 += (char)messageFromServer_3490; // 判断读到的的字符串是否为 "\r\n\r\n", 如果是，则已经得到完整的head,将isHead_3490置为true，结束while循环 while (messageFromServer_3490 != -1 && !isHead_3490) { switch (messageFromServer_3490) { case 13: messageFromServer_3490 = rFromServer_3490.read(); switch (messageFromServer_3490) { case 10: headMessage_3490 += (char) messageFromServer_3490; if ((char) (messageFromServer_3490 = rFromServer_3490.read()) == ('\r')) if ((char) (messageFromServer_3490 = rFromServer_3490.read()) == ('\n')) isHead_3490 = true; break; default: break; } break; default: break; } if (isHead_3490) break; messageFromServer_3490 = rFromServer_3490.read(); headMessage_3490 += (char) messageFromServer_3490; } System.out.println("服务端的响应报文:\n" + headMessage_3490 + "\n"); /* * 保存文件 */ int fileLength_3490 = rFromServer_3490.available(); byte[] bufForFile_3490 = new byte[fileLength_3490]; rFromServer_3490.read(bufForFile_3490, 0, bufForFile_3490.length); System.out.println("请输入您要保存的文件的名字: "); String fileName_3490 = rFromIn_3490.readLine(); FileOutputStream wToFile_3490 = new FileOutputStream(fileName_3490); wToFile_3490.write(bufForFile_3490); wToFile_3490.flush(); wToFile_3490.close(); System.out.println("文件已保存！"); clientSocket_3490.close(); } catch (UnknownHostException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } 基于TCP的聊天程序 ~~~~~~~~~~~~~~~~~~~~服务端~~~~~~~~~~~~~~~~~~~~~~~ package network; /* Java学习之网络编程_TCPServer * @author yeS * @version 1.0.0 */ import java.io.*; import java.net.*; public class TCPServer { public static int PORT = 8002; public static void main(String[] args) { String readline = null; try { //开启服务器 ServerSocket ss = new ServerSocket(PORT); System.out.println("服务器已启动"); //等待来自客户端的连接 Socket sc = ss.accept(); /* * 定义 * 从键盘读取的流: rFormIn * 从客户端读取的流: rFromClient * 输出流: pwToClient */ BufferedReader rFromIn = new BufferedReader( new InputStreamReader(System.in)); BufferedReader rFromClient = new BufferedReader( new InputStreamReader(sc.getInputStream())); PrintWriter pwToClient = new PrintWriter(sc.getOutputStream()); //将从客户端传来的数据打印出来 System.out.println("Client: " + rFromClient.readLine()); //将服务器从键盘输入的数据作为字符串赋值给readline readline = rFromIn.readLine(); //当输入的数据不是exit的时候，进入循环 while(!readline.equalsIgnoreCase("exit")) { //输出服务端从键盘输入的内容 System.out.println("Server: " + readline); //并将内容发送到客户端 pwToClient.println(readline); pwToClient.flush(); //打印客户端传来的数据 System.out.println("Client: " + rFromClient.readLine()); //再将服务器从键盘输入的数据作为字符串赋值给readline readline = rFromIn.readLine(); } rFromClient.close(); pwToClient.close(); sc.close(); ss.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } ~~~~~~~~~~~~~~~~~~~~客户端~~~~~~~~~~~~~~~~~~~~~~~ package network; /* Java学习之网络编程_TCPClient * @author yeS * @version 1.0.0 */ import java.io.*; import java.net.*; public class TCPClient { public static void main(String[] args) { String readline = null; try { //和服务端建立连接 Socket ss = new Socket("localhost",8002); System.out.println("已经和" + ss.getInetAddress() + "建立连接，现在你们可以通话了"); /* * 定义 * 从键盘读取数据的流: rFromIn * 从服务端读取数据的流: rFromServer * 传送到服务端的流: pwToServer */ BufferedReader rFromIn = new BufferedReader( new InputStreamReader(System.in)); BufferedReader rFromServer = new BufferedReader( new InputStreamReader(ss.getInputStream())); PrintWriter pwToServer = new PrintWriter(ss.getOutputStream()); //从键盘读取数据，将数据转换成字符串赋值给readline readline = rFromIn.readLine(); //如果从键盘输入的数据不是exit则进入循环 while(!readline.equalsIgnoreCase("exit")) { //打印客户端从键盘输入的内容 System.out.println("Client: " + readline); //并将内容传给服务端 pwToServer.println(readline); pwToServer.flush(); //输出从服务端传来的数据 System.out.println("Server: " + rFromServer.readLine()); //从键盘读取数据，将数据转换成字符串赋值给readline readline = rFromIn.readLine(); } rFromServer.close(); pwToServer.close(); ss.close(); } catch (UnknownHostException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }