生产者消费者以及LRU

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//生产者消费者//wait()和notify()import java.util.LinkedList;    class Producer extends Thread {private final LinkedList<Object> storeHouse;        private final int MAX;    public Producer(LinkedList<Object> storeHouse,int MAX){this.storeHouse=storeHouse;this.MAX=MAX;}        public void run() {            while (true) {                synchronized (storeHouse) {                    try {                        while (storeHouse.size() == MAX) {                            storeHouse.wait();                        }                        Object newOb = new Object();                        if (storeHouse.add(newOb)) {                            Thread.sleep((long) (Math.random() * 3000));                            storeHouse.notify();                        }                    } catch (InterruptedException ie) {                        System.out.println("producer is interrupted!");                    }                }            }        }    }    class Comsumer extends Thread {private final LinkedList<Object> storeHouse;        private final int MAX;    public Comsumer(LinkedList<Object> storeHouse,int MAX){this.storeHouse=storeHouse;this.MAX=MAX;}        public void run() {            while (true) {                synchronized (storeHouse) {                    try {                        while (storeHouse.size() == 0) {                            storeHouse.wait();                        }                        storeHouse.removeLast();                        Thread.sleep((long) (Math.random() * 3000));                        storeHouse.notify();                    } catch (InterruptedException ie) {                        System.out.println("Consumer is interrupted");                    }                }            }        }    }//生产者消费者//阻塞队列的形式import java.util.concurrent.BlockingQueue;import java.util.concurrent.LinkedBlockingQueue;import java.util.logging.Level;import java.util.logging.Logger;public class ProducerConsumerPattern {    public static void main(String args[]){       //Creating shared object     BlockingQueue sharedQueue = new LinkedBlockingQueue();      //Creating Producer and Consumer Thread     Thread prodThread = new Thread(new Producer(sharedQueue));     Thread consThread = new Thread(new Consumer(sharedQueue));     //Starting producer and Consumer thread     prodThread.start();     consThread.start();    } }//Producer Class in javaclass Producer implements Runnable {    private final BlockingQueue sharedQueue;    public Producer(BlockingQueue sharedQueue) {        this.sharedQueue = sharedQueue;    }    @Override    public void run() {        for(int i=0; i<10; i++){            try {                System.out.println("Produced: " + i);                sharedQueue.put(i);            } catch (InterruptedException ex) {                Logger.getLogger(Producer.class.getName()).log(Level.SEVERE, null, ex);            }        }    }}//Consumer Class in Javaclass Consumer implements Runnable{    private final BlockingQueue sharedQueue;    public Consumer (BlockingQueue sharedQueue) {        this.sharedQueue = sharedQueue;    }      @Override    public void run() {        while(true){            try {                System.out.println("Consumed: "+ sharedQueue.take());            } catch (InterruptedException ex) {                Logger.getLogger(Consumer.class.getName()).log(Level.SEVERE, null, ex);            }        }    }    }Output:Produced: 0Produced: 1Consumed: 0Produced: 2Consumed: 1Produced: 3Consumed: 2Produced: 4Consumed: 3Produced: 5Consumed: 4Produced: 6Consumed: 5Produced: 7Consumed: 6Produced: 8Consumed: 7Produced: 9Consumed: 8Consumed: 9

//LRUpublic class LRUCache {    int capacity;    HashMap<Integer, Node> map = new HashMap<Integer, Node>();    Node head=null;    Node end=null;     public LRUCache(int capacity) {        this.capacity = capacity;    }     public int get(int key) {        if(map.containsKey(key)){            Node n = map.get(key);            remove(n);            setHead(n);            return n.value;        }         return -1;    }     public void remove(Node n){        if(n.pre!=null){            n.pre.next = n.next;        }else{            head = n.next;        }         if(n.next!=null){            n.next.pre = n.pre;        }else{            end = n.pre;        }     }     public void setHead(Node n){        n.next = head;        n.pre = null;         if(head!=null)            head.pre = n;         head = n;         if(end ==null)            end = head;    }     public void set(int key, int value) {        if(map.containsKey(key)){            Node old = map.get(key);            old.value = value;            remove(old);            setHead(old);        }else{            Node created = new Node(key, value);            if(map.size()>=capacity){                map.remove(end.key);                remove(end);                setHead(created);             }else{                setHead(created);            }                 map.put(key, created);        }    }}

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