JAVAマルチスレッドは生産者消費者の実例を実現します。

package consumerProducer; 
 
public class Product { 
private String id; 
 
public String getId() { 
  return id; 
} 
 
public void setId(String id) { 
  this.id = id; 
} 
public Product(String id) 
{ 
  this.id=id; 
 
} 
public String toString() 
{ 
  return "product "+id;   
 
} 
 
} 

package consumerProducer; 
import java.util.*; 
public class Pool { 
private int number=0; 
 
private List<Product>products=new LinkedList<Product>(); 
 
 
public int getNumber() { 
  return number; 
} 
public void setNumber(int number) { 
  this.number = number; 
} 
public synchronized Product consumeProduct(){  //    synchronized    
  if(products.size()>0) 
  {    Product p= products.get(0); 
    products.remove(0); 
    number--; 
    return p; 
 
  } 
  else 
    return null; 
} 
public synchronized void addProduct(Product p){  //    synchronized    
       
      products.add(p); 
      number++; 
} 
 
} 

package consumerProducer; 
 
public class Consumer implements Runnable { 
 private String id; 
  Pool pool; 
  public Consumer(String id,Pool pool) 
  { 
    this.id=id; 
    this.pool=pool; 
     
  } 
  @Override 
  public void run() { 
    while(!Thread.currentThread().interrupted()) 
    { 
      Product product=null; 
      synchronized(pool){ 
        while(pool.getNumber()<=0)//     
        { 
          try { 
            pool.wait();//      
          } catch (InterruptedException e) { 
            // TODO Auto-generated catch block 
            e.printStackTrace(); 
          } 
         
       
          
        } 
         product=pool.consumeProduct(); 
      } 
        System.out.println("consuming "+id+product.toString()); 
        try { 
          Thread.sleep(1000); 
        } catch (InterruptedException e) { 
          // TODO Auto-generated catch block 
          e.printStackTrace(); 
        } 
         
       
       
       
    } 
  } 
 
} 

package consumerProducer; 
 
public class Producer implements Runnable{ 
  private int i_p=0; 
  private String id; 
  Pool pool; 
  int i=0; 
  public Producer(String id ,Pool pool) 
  { 
     
    this.id=id; 
    this.pool=pool; 
  } 
  public Product createProduct() 
  { 
     
    return new Product(String.valueOf(++i_p)); 
     
  } 
  @Override 
  public void run() { 
    // TODO Auto-generated method stub 
   while(!Thread.currentThread().interrupted()) 
   { 
     Product p=new Product(String.valueOf(++i_p)); 
     try { 
      Thread.sleep(1000); 
    } catch (InterruptedException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
    } 
     synchronized(pool) 
     { 
       pool.addProduct(p); 
       System.out.println("producer "+id+" adding product...."+p.toString()); 
       pool.notifyAll(); 
     }  
      
   } 
     
  } 
 
} 

package consumerProducer; 
 
public class Main { 
 
  public static void main(String[] args) { 
    // TODO Auto-generated method stub 
    Pool pool=new Pool(); 
   for(int i=0;i<5;i++) 
   { 
     Thread consumer=new Thread(new Consumer("consumer "+i,pool)); 
     Thread producer=new Thread(new Producer("producer "+i,pool)); 
     consumer.start(); 
     producer.start(); 
      
   } 
  } 
 
}