我正在创建一个图书馆模拟器，里面有一个图书馆，一个图书管理员和多个借阅者对象。它涉及多个借用者线程和一个同时运行的图书管理员线程，执行诸如请求书籍，还书等任务。
我一直在使用同步功能来确保每个借款人内部的功能不会变得混乱，但现在我试图弄清楚，一旦借款人开始一个功能，将其放入一个带有集合的队列中在条目之间休眠，并且输出将在间隔内发布到控制台。
我的问题是，一旦借款人获得了一个功能，例如RequestBooks，而不是简单地将它输出到控制台，并且由于存在多个借用者的事实，有什么方法可以将函数的输出或Borrower在队列中执行该函数，所以，比方说，每隔3秒，队列处理一个条目，然后运行该函数，以便放入队列的每个函数的输出以偶数间隔打印出来。
在某些时候，我将使用一个Lock系统（我也不确定如何执行多个线程），这将决定哪个借用者向队列发送一个函数，如果这有助于任何混淆。
借款人代码如下：
public class Borrower extends Thread {
private int noOfBooks;
private Set<Book> BooksBorrowed;
private Set<Integer> booksRequested;
private int id;
private int runs;
private Library library;
private Random randSleep = new Random();
public Borrower(int id, Library library, int runs) {
this.library = library;
this.id = id;
this.runs = runs;
noOfBooks = 1;
}
public Borrower(){}
public String getLoans() {
String output = "";
for(Book b : BooksBorrowed) {
output +=" "+b.getBookId()+" ";
}
return output;
}
public void run()
{
try {
Initialize();
for(int i = 0; i < runs; i++) {
RequestBooks();
ReturnBooks();
}
} finally {}
}
public synchronized void Initialize() {
int min = 1;
int max = 10;
Random r = new Random();
noOfBooks = r.nextInt(max - min + 1) + min;
System.out.println("--------------------------");
System.out.println("Borrower "+id+" Starting");
notifyAll();
}
public synchronized void RequestBooks () {
Random r2 = new Random();
Book temp = null;
ArrayList<Book>books = new ArrayList<Book>(library.getBooks());
ArrayList<Integer>Chosen = new ArrayList<Integer>();
for(int i = 0; i < noOfBooks; i++){
int index = r2.nextInt(books.size());
temp = books.get(index);
int tempId = temp.getBookId();
Chosen.add(tempId);
}
System.out.println("--------------------------");
System.out.println("\nBorrower "+id+" requests " +noOfBooks+" Books from Library ");
booksRequested = new HashSet<Integer>(Chosen);
String requestedBooks = "";
for(Integer bookid : Chosen) {
requestedBooks = requestedBooks+bookid+" ";
booksRequested.add(bookid);
}
System.out.println("Borrower "+id+" request Books: "+requestedBooks);
BooksBorrowed = library.RQST(id,booksRequested);
ArrayList<Book> chosenBooks = new ArrayList<Book>();
chosenBooks.addAll(BooksBorrowed);
System.out.println("Books requested by Borrower "+id+" : "+requestedBooks+"\n");
String receivedBooks = "";
Book[]BookArray = BooksBorrowed.toArray(new Book[BooksBorrowed.size()]);
for(Book b : BookArray) {
receivedBooks = receivedBooks+b.getBookId()+" ";
}
System.out.println("Borrower "+id+" Books recieved :"+receivedBooks);
System.out.println("--------------------------");
notifyAll();
}
public synchronized void ReturnBooks() {
Set<Integer> BooksReturned;
ArrayList<Integer> returningBooks = new ArrayList<Integer>();
String returnedBooks = "";
ArrayList<Book> borrowed = new ArrayList<Book>(BooksBorrowed);
for (Book b : borrowed) {
returningBooks.add(b.getBookId());
returnedBooks = returnedBooks+b.getBookId()+" ";
}
BooksReturned = new HashSet<Integer>(returningBooks);
library.RTRN(BooksReturned);
System.out.println("\nBorrower "+id+" returned books to library: "+returnedBooks+"\n");
}
这是图书管理员代码：
public class Librarian extends Thread {
Library library;
int runs = 0;
public Librarian(Library library, int runs) {
this.library = library;
this.runs = runs;
}
public ArrayList<Book> AddBooks() {
ArrayList<Book> addbooks = new ArrayList<Book>();
addbooks.add(new Book("The Lord of the Rings, The Fellowship",1,5));
addbooks.add(new Book("The Lord of the Rings, Two Towers",2,5));
addbooks.add(new Book("The Lord of the Rings, Return of King",3,5));
addbooks.add(new Book("The Hunger Games",4,5));
addbooks.add(new Book("A Game of Thrones",5,5));
addbooks.add(new Book("Storm of Swords",6,5));
addbooks.add(new Book("The Eagles Lair",7,5));
addbooks.add(new Book("The Philosophers Stone",8,5));
addbooks.add(new Book("Programming in Java",9,2));
addbooks.add(new Book("Hit and Run",10,5));
addbooks.add(new Book("The man in the Iron Mask",11,5));
addbooks.add(new Book("A Dance With Dragons",12,5));
addbooks.add(new Book("A Feast for Crows",13,5));
addbooks.add(new Book("Jack the Ripper",14,1));
addbooks.add(new Book("The Oddessey",15,1));
return addbooks;
}
@Override
public void run() {
try {
//Random rsleep = new Random();
Initialize();
for(int i = 0;i < runs; i++) {
//sleep(rsleep.nextInt(10000));
getBorrowers();
}
} catch(Exception e){}
}
public void Initialize(){
System.out.println("\nStarting Librarian");
System.out.println("Library Initializing\n");
}
public void LibraryStatus() {
}
public void getBorrowers() {
System.out.println("\nGetting Current Borrowers\n");
String BorrowedBooks ="";
Set<Entry<Integer,Set<Book>>> tempset = library.getBorrowers().entrySet();
for(Entry<Integer,Set<Book>> entry : tempset) {
for(Book b : entry.getValue()) {
BorrowedBooks = BorrowedBooks + b.toString()+"";
}
System.out.println("Borrower "+entry.getKey()+" borrowed books : "+BorrowedBooks);
BorrowedBooks ="";
}
}
public void setLibrary(Library library2) {
this.library = library2;
}
}
以下是控制其他人的主要课程：
public class LibraryModel {
Library library = new Library();
Librarian librarian;
ArrayList<Borrower> BorrowArray = new ArrayList<Borrower>();
int runs = 0;
int isFinished;
Boolean isActive = true;
public LibraryModel() {
library.AddBooks();
}
public static void main(String[]args)
{
int borrowCount = 0;
System.out.println("Welcome to the Library Simulator\n");
LibraryModel model = new LibraryModel();
char quit = 'y';
Scanner sc = new Scanner(System.in);
while(quit != 'q') {
System.out.println("\n[S = start, A = About, Q = quit]");
String a = sc.next();
switch (a) {
case "S":
model.isActive = true;
System.out.println("Please enter the number of Borrowers\n");
borrowCount = sc.nextInt();
System.out.println("Please enter how many runs the Program will run");
model.runs = sc.nextInt();
model.isFinished = model.runs;
model.librarian = new Librarian(model.library,model.runs);
for(int i = 0 ;i < borrowCount; i++) {
model.getBorrowers().add(new Borrower(i+1,model.getLibrary(),model.runs));
}
model.librarian().start();
for(Borrower b : model.getBorrowers()) {
b.start();
}
try {
model.librarian.join();
for(Borrower b : model.getBorrowers()) {
b.join();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
break;
case "A":
break;
case "Q" :
quit = 'q';
break;
default :
System.out.println("Incorrect Entry, please enter a correct");
break;
}
}
}
public Library getLibrary() {
return library;
}
public ArrayList<Borrower> getBorrowers() {
return BorrowArray;
}
public Librarian librarian() {
return librarian;
}
public int runs() {
return runs;
}
}
提前感谢您的帮助