86 lines
2.2 KiB
Java
86 lines
2.2 KiB
Java
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import java.util.concurrent.locks.*;
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class FullException extends Exception {
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FullException(String msg) { super(msg); }
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}
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class Box<T> {
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private T[] items = (T[]) new Object[3];
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private int count = 0;
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private Lock lock = new ReentrantLock();
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private Condition notFull = lock.newCondition(), notEmpty = lock.newCondition();
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void add(T item) throws FullException, InterruptedException {
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lock.lock();
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try {
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if (count == items.length) throw new FullException("Box is full");
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while (count == items.length) notFull.await();
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items[count++] = item;
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notEmpty.signal();
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} finally {
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lock.unlock();
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}
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}
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T retrieve() throws InterruptedException {
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lock.lock();
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try {
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while (count == 0) notEmpty.await();
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T item = items[--count];
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notFull.signal();
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return item;
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} finally {
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lock.unlock();
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}
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}
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boolean isEmpty() {
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return count == 0;
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}
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void clear() {
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count = 0;
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}
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}
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class Student {
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String name;
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Student(String name) { this.name = name; }
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public String toString() { return name; }
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}
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public class Main {
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public static void main(String[] args) throws Exception {
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Box<Integer> intBox = new Box<>();
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Box<String> strBox = new Box<>();
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Box<Student> studentBox = new Box<>();
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Thread t1 = new Thread(() -> {
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try {
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intBox.add(1);
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intBox.add(2);
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intBox.add(3);
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System.out.println(intBox.retrieve());
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} catch (Exception e) { e.printStackTrace(); }
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});
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Thread t2 = new Thread(() -> {
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try {
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strBox.add("Hello");
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System.out.println(strBox.retrieve());
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} catch (Exception e) { e.printStackTrace(); }
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});
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Thread t3 = new Thread(() -> {
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try {
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studentBox.add(new Student("Alice"));
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System.out.println(studentBox.retrieve());
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} catch (Exception e) { e.printStackTrace(); }
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});
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t1.start();
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t2.start();
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t3.start();
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}
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}
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