library.java

线程通信

import java.util.*;
public class Library{
	
	private List book;
	private List borrower;
	
	private HashMap titleBook=new HashMap(100);
	private HashMap idBorrower=new HashMap(100);;
	
	
	public Library(List book,List borrower){
		this.book=book;
		this.borrower=borrower;
		for(int i=0;i<book.size();i++){
			Book b=(Book)book.get(i);
			titleBook.put(b.getTitle(),b);
		}
		for(int i=0;i<borrower.size();i++){
			Borrower b=(Borrower)borrower.get(i);
			idBorrower.put(b.getId(),b);
		}
	} 
	

	/*precondition: id must exist*/
	public Borrower getBorrower(String id){
		return (Borrower)idBorrower.get(id);
	}
	
	
	public Book getBook(String title){
		return (Book)titleBook.get(title);
	}

	public boolean authenicate(String id){
		return idBorrower.containsKey(id);
		
	}	
}