传统的容器并没有实现线程安全，所以在多线程的情况下，并不管用。本文首先自己手写一个并发Queue引出全文：
import java.util.LinkedList;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
public class MyQueue {
//1 需要一个承装元素的集合
private LinkedList<Object> list = new LinkedList<Object>();
//2 需要一个计数器
private AtomicInteger count = new AtomicInteger(0);
//3 需要制定上限和下限
private final int minSize = 0;
private final int maxSize ;
//4 构造方法
public MyQueue(int size){
this.maxSize = size;
}
//5 初始化一个对象 用于加锁
private final Object lock = new Object();
//put(anObject): 把anObject加到BlockingQueue里,如果BlockQueue没有空间,则调用此方法的线程被阻断，直到BlockingQueue里面有空间再继续.
public void put(Object obj){
synchronized (lock) {
while(count.get() == this.maxSize){
try {
lock.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
//1 加入元素
list.add(obj);
//2 计数器累加
count.incrementAndGet();
//3 通知另外一个线程（唤醒）
lock.notify();
System.out.println("新加入的元素为:" + obj);
}
}
//take: 取走BlockingQueue里排在首位的对象,若BlockingQueue为空,阻断进入等待状态直到BlockingQueue有新的数据被加入.
public Object take(){
Object ret = null;
synchronized (lock) {
while(count.get() == this.minSize){
try {
lock.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
//1 做移除元素操作
ret = list.removeFirst();
//2 计数器递减
count.decrementAndGet();
//3 唤醒另外一个线程
lock.notify();
}
return ret;
}
public int getSize(){
return this.count.get();
}
public static void main(String[] args) {
final MyQueue mq = new MyQueue(5);
mq.put("a");
mq.put("b");
mq.put("c");
mq.put("d");
mq.put("e");
System.out.println("当前容器的长度:" + mq.getSize());
Thread t1 = new Thread(new Runnable() {
@Override
public void run() {
mq.put("f");
mq.put("g");
}
},"t1");
t1.start();
Thread t2 = new Thread(new Runnable() {
@Override
public void run() {
Object o1 = mq.take();
System.out.println("移除的元素为:" + o1);
Object o2 = mq.take();
System.out.println("移除的元素为:" + o2);
}
},"t2");
try {
TimeUnit.SECONDS.sleep(2);
} catch (InterruptedException e) {
e.printStackTrace();
}
t2.start();
}
}
并发类容器是java.util.concurrent包中提供的用于并发编程的容器，主要有以下大类：
package com.xushu.multi;
import java.util.Vector;
public class Ticket {
public static void main(String[] args) {
final Vector<String> tickets = new Vector<String>();
for(int i = 1; i < 1000; i++){
tickets.add("火车票" + i);
}
for(int i = 1; i <= 10; i++){
new Thread("线程" + i){
public void run() {
while(true){
if(tickets.isEmpty())
break;
System.out.println(Thread.currentThread().getName() + "---" + tickets.remove(0));
}
}
}.start();
}
}
}
DelayQueue的演示
WangMing.java
package com.xushu.multi;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;
public class WangMing implements Delayed{
private String name;
//身份证
private String id;
//截止时间
private long endTime;
//定义时间工具类
private TimeUnit timeUnit = TimeUnit.SECONDS;
public WangMing(String name, String id, Long endTime){
this.name = name;
this.id = id;
this.endTime = endTime;
}
public String getName(){
return this.name;
}
public String getId(){
return this.id;
}
@Override
public int compareTo(Delayed o) {
WangMing w = (WangMing)o;
return this.getDelay(this.timeUnit) - w.getDelay(this.timeUnit) > 0 ? 1 : 0;
}
/**
* 用来判断是否到了截止时间
*/
@Override
public long getDelay(TimeUnit unit) {
return endTime - System.currentTimeMillis();
}
}
WangBa.java
package com.xushu.multi;
import java.util.concurrent.DelayQueue;
public class WangBa implements Runnable{
private DelayQueue<WangMing> queue = new DelayQueue<WangMing>();
public boolean yinye = true;
public void shangji(String name,String id,int money){
WangMing man = new WangMing(name, id, 1000 * money + System.currentTimeMillis());
System.out.println("网名"+man.getName()+" 身份证"+man.getId()+"交钱"+money+"块,开始上机...");
this.queue.add(man);
}
public void xiaji(WangMing man){
System.out.println("网名"+man.getName()+" 身份证"+man.getId()+"时间到下机...");
}
@Override
public void run() {
while(yinye){
WangMing man;
try {
man = queue.take();
xiaji(man);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
public static void main(String[] args) {
try{
System.out.println("网吧开始营业");
WangBa speed = new WangBa();
Thread shangwang = new Thread(speed);
shangwang.start();
speed.shangji("路人甲", "123", 1);
speed.shangji("路人乙", "234", 10);
speed.shangji("路人丙", "345", 5);
}
catch(Exception e){
e.printStackTrace();
}
}
}
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