多线程编程

code/Java/java-concurrency/src/main/java/com/heibaiying/threadPool/J1_ThreadPool.java

@@ -0,0 +1,25 @@
+package com.heibaiying.threadPool;
+
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+/**
+ * 线程池的基本使用
+ */
+public class J1_ThreadPool {
+
+	static class Task implements Runnable {
+		@Override
+		public void run() {
+			System.out.println(Thread.currentThread().getName() + "正在执行");
+		}
+	}
+
+	public static void main(String[] args) {
+		ExecutorService executorService = Executors.newFixedThreadPool(10);
+		for (int i = 0; i < 100; i++) {
+			executorService.submit(new Task());
+		}
+		executorService.shutdown();
+	}
+}

code/Java/java-concurrency/src/main/java/com/heibaiying/threadPool/J2_ScheduledTask.java

@@ -0,0 +1,46 @@
+package com.heibaiying.threadPool;
+
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * 计划任务
+ */
+public class J2_ScheduledTask {
+
+	private static long cacheTime = System.currentTimeMillis();
+
+	static class Task implements Runnable {
+
+		private String type;
+
+		Task(String type) {
+			this.type = type;
+		}
+
+		@Override
+		public void run() {
+			try {
+				Thread.sleep(5000);
+				long nowTime = System.currentTimeMillis();
+				System.out.println(type + Thread.currentThread().getId() + "执行耗时" + (nowTime - cacheTime) + "毫秒");
+				cacheTime = nowTime;
+			} catch (InterruptedException e) {
+				e.printStackTrace();
+			}
+		}
+	}
+
+	public static void main(String[] args) {
+		ScheduledExecutorService pool = Executors.newScheduledThreadPool(10);
+		// 只执行一次
+		pool.schedule(new Task("schedule"), 2, TimeUnit.SECONDS);
+		// 指定2秒为固定周期执行，如果项目执行耗时5秒，则项目结束后立马执行下一次任务，所以输出的时间间隔为5秒
+		pool.scheduleAtFixedRate(new Task("FixedRate"), 0, 2, TimeUnit.SECONDS);
+		// 总是在上一次项目结束后间隔指定周期执行，所以项目耗时5秒，还需要间隔2秒执行，所以输出的时间间隔为7秒
+		pool.scheduleWithFixedDelay(new Task("WithFixedDelay"), 0, 2, TimeUnit.SECONDS);
+		// pool.shutdown();
+	}
+
+}

code/Java/java-concurrency/src/main/java/com/heibaiying/threadPool/J3_CustomThreadPool.java

@@ -0,0 +1,46 @@
+package com.heibaiying.threadPool;
+
+import java.util.concurrent.*;
+
+public class J3_CustomThreadPool {
+
+	private static int i = 0;
+	private static CountDownLatch latch = new CountDownLatch(1000);
+
+	static class Task implements Runnable {
+
+		@Override
+		public void run() {
+			increase();
+		}
+
+		private void increase() {
+			synchronized (this) {
+				i++;
+			}
+			System.out.println(Thread.currentThread().getName() + "输出:" + i);
+			latch.countDown();
+		}
+	}
+
+	public static void main(String[] args) throws InterruptedException {
+
+		// 自定义线程池
+		ExecutorService executorService = new ThreadPoolExecutor(10, 20, 0L, TimeUnit.MILLISECONDS,
+			new LinkedBlockingQueue<>(),
+			r -> {
+				Thread thread = new Thread(r);
+				thread.setDaemon(true);
+				System.out.println("create" + thread.getName());
+				return thread;
+			});
+
+		Task task = new Task();
+		for (int i = 0; i < 1000; i++) {
+			executorService.submit(task);
+		}
+		latch.await();
+		System.out.println("最后的结果是" + i);
+		executorService.shutdown();
+	}
+}

code/Java/java-concurrency/src/main/java/com/heibaiying/threadPool/J4_ExtendedThreadPool.java

@@ -0,0 +1,55 @@
+package com.heibaiying.threadPool;
+
+import java.util.concurrent.*;
+
+public class J4_ExtendedThreadPool {
+
+	private static int i = 0;
+	private static CountDownLatch latch = new CountDownLatch(1000);
+
+	static class Task implements Runnable {
+
+		@Override
+		public void run() {
+			increase();
+		}
+
+		private void increase() {
+			synchronized (this) {
+				i++;
+			}
+			System.out.println(Thread.currentThread().getName() + "输出:" + i);
+			latch.countDown();
+		}
+	}
+
+	public static void main(String[] args) throws InterruptedException {
+
+		// 自定义线程
+		ExecutorService executorService = new ThreadPoolExecutor(10, 20, 0L, TimeUnit.MILLISECONDS,
+			new LinkedBlockingQueue<>()) {
+			@Override
+			protected void beforeExecute(Thread t, Runnable r) {
+				System.out.println("线程" + t.getName() + "准备执行");
+			}
+
+			@Override
+			protected void afterExecute(Runnable r, Throwable t) {
+				System.out.println("线程" + r + "执行结束");
+			}
+
+			@Override
+			protected void terminated() {
+				System.out.println("线程池退出");
+			}
+		};
+
+		Task task = new Task();
+		for (int i = 0; i < 1000; i++) {
+			executorService.submit(task);
+		}
+		latch.await();
+		System.out.println("最后的结果是" + i);
+		executorService.shutdown();
+	}
+}