queue.java

java编程开发技巧与实例的编译测试通过的所有例程

//import java.awt.*;
import java.awt.List;

public class Queue
{
	private List customers	=	new List();
	private synchronized Object performAction(String cmd, Object obj)
	{
		/*if (cmd.equals("insert"))
		{
			if (!customers.isFull())
				customers.add(obj);
			notify();
			return null;
		}
		else if (cmd.equals("size"))
		{
			return new Integer(customers.getSize());
		}
		else if (cmd.equals("retrieve"))
		{
			while (customers.getSize() == 0)
			{
				try
				{	wait();	}
				catch	(InterruptedException ie)
				{	System.out.println("Synch error in queue: " + ie);	}
			}
			Customer c	=	(Customer)customers.get(0);
			customers.delete(0);
			return c;
		}
		else*/
			return null;
	}
	public void insert(Customer c)
	{	performAction("insert", c);}
	public int getSize()
	{	return ((Integer)performAction("size", null)).intValue();	}
	public Customer requestCustomer()
	{	return (Customer)performAction("retrieve", null);}
}