Java 并发编程实践基础 读书笔记： 第一章 JAVA并发编程实践基础
1.创建线程的方式：
1 /** 2 * StudySjms 3 * <p> 4 * Created by haozb on 2018/2/28. 5 */ 6 public class ThreadDemo extends Thread { 7 /** 8 * 定义线程的名字 9 * @param name 10 */ 11 public ThreadDemo(String name) { 12 super(name); 13 } 14 15 @Override 16 public void run() { 17 for (int i = 0; i < 20; i++) { 18 System.out.println(this.getName()+":"+i); 19 } 20 } 21 22 public static void main(String[] args) { 23 for (int i = 0; i < 5; i++) { 24 new ThreadDemo("name"+i).start(); 25 } 26 } 27 }
1 /** 2 * StudySjms 3 * <p> 4 * Created by haozb on 2018/2/28. 5 */ 6 public class ThreadDemo implements Runnable { 7 @Override 8 public void run() { 9 for (int i = 0; i < 5; i++) { 10 System.out.println(Thread.currentThread().getName()+":"+i); 11 } 12 } 13 14 public static void main(String[] args) { 15 /* Runnable demo = new ThreadDemo(); 16 for (int i = 0; i < 3; i++) { 17 new Thread(demo,""+i).start(); 18 }*/ 19 20 // 也可以直接采用内名内部类方式来创建 21 final int num = 5; 22 for (int i = 0; i < 3; i++) { 23 new Thread(new Runnable() { 24 @Override 25 public void run() { 26 for (int i = 0; i < num; i++) { 27 System.out.println(Thread.currentThread().getName()+":"+i); 28 } 29 } 30 },""+i).start(); 31 } 32 } 33 }
Executors其实就是工厂类，用来创建各种的线程池;
1 import java.util.concurrent.*; 2 3 /** 4 * StudySjms 5 * <p> 6 * Created by haozb on 2018/2/28. 7 */ 8 public class ThreadPool { 9 public static void main(String[] args) { 10 //ExecutorService pool = Executors.newFixedThreadPool(2); 11 // 这种是固定线程数的线程池，控制了现场的最大并发量 12 //ExecutorService pool = Executors.newCachedThreadPool(); 13 // 这种没有长度限制，会自动控制池的大小，如果任务多了，会创建新现场，如果任务少了，会回收线程 14 //ScheduledExecutorService pool = Executors.newScheduledThreadPool(5); 15 /* 16 这种例子是延迟3秒执行 17 pool.schedule(new Runnable() { 18 @Override 19 public void run() { 20 21 } 22 },3,TimeUnit.SECONDS);*/ 23 /* 24 这种是延迟1秒 每3秒执行一次 25 pool.scheduleAtFixedRate(new Runnable() { 26 @Override 27 public void run() { 28 29 } 30 },1,3,TimeUnit.SECONDS);*/ 31 /* 32 相当于单线程执行任务，有顺序 33 ExecutorService singleThreadExecutor = Executors.newSingleThreadExecutor(); 34 */ 35 36 ExecutorService pool = new ThreadPoolExecutor(5,100,0L, TimeUnit.MILLISECONDS,new LinkedBlockingDeque<Runnable>()); 37 for (int i = 0; i < 10; i++) { 38 final int tmp = i; 39 Runnable run = new Runnable() { 40 @Override 41 public void run() { 42 long time = (long)(Math.random()*1000); 43 System.out.println(Thread.currentThread().getName()+":"+tmp+"sleeping"+time); 44 45 try { 46 Thread.sleep(time); 47 } catch (InterruptedException e) { 48 e.printStackTrace(); 49 } 50 } 51 }; 52 pool.execute(run); 53 } 54 pool.shutdown(); 55 } 56 }
线程的基本控制方法：
Thread.sleep(); 使线程睡眠，放弃cpu
join ：使一个线程等待另一个线程完事在执行。eg: t1里面，t2.join() t1暂停执行，立即执t2,t2执行完事之后再去执行t1
可以有参数，t2.join(10); 表示为t1只等t210毫秒就继续执行了
interrupt()：中断线程，有些时候需要在线程执行过程中中断线程。
