Java并发

code/Java/java-concurrency/src/main/java/com/heibaiying/condition/AwaitAndSignal.java

@@ -32,6 +32,7 @@ public class AwaitAndSignal {
 		Thread thread1 = new Thread(new IncreaseTask());
 		thread1.start();
 		Thread.sleep(2000);
+		// 必须要再次获取该重入锁，否则会抛出IllegalMonitorStateException异常
 		lock.lock();
 		condition.signal();
 		lock.unlock();

code/Java/java-concurrency/src/main/java/com/heibaiying/readWriteLock/ReadWriteLock.java

@@ -70,7 +70,7 @@ public class ReadWriteLock {
 
 	public static void main(String[] args) throws InterruptedException {
 
-		// 耗时2秒，写锁是互斥的，但读锁是并行的
+		// 写锁是排它的，但读锁是共享的，耗时3秒左右
 		for (int j = 0; j < 2; j++) {
 			Thread thread = new Thread(new Write(writeLock, String.valueOf(j)));
 			thread.start();
@@ -81,7 +81,7 @@ public class ReadWriteLock {
 		}
 
 
-		// 使用重入锁时，读锁彼此之间也是互斥的
+		// 使用重入锁时耗时20秒左右
 		for (int j = 0; j < 2; j++) {
 			Thread thread = new Thread(new Write(reentrantLock, String.valueOf(j)));
 			thread.start();

code/Java/java-concurrency/src/main/java/com/heibaiying/synchronized_/J1_ThreadUnsafe.java

@@ -8,8 +8,9 @@ public class J1_ThreadUnsafe {
 	private static int i = 0;
 
 	public static void main(String[] args) throws InterruptedException {
-		Thread thread1 = new Thread(new IncreaseTask());
-		Thread thread2 = new Thread(new IncreaseTask());
+		IncreaseTask task = new IncreaseTask();
+		Thread thread1 = new Thread(task);
+		Thread thread2 = new Thread(task);
 		thread1.start();
 		thread2.start();
 		// 等待线程结束再打印返回值

code/Java/java-concurrency/src/main/java/com/heibaiying/waitAndNotify/J3_WaitAndNotify.java

@@ -21,9 +21,9 @@ public class J3_WaitAndNotify {
 		}).start();
 		new Thread(() -> {
 			synchronized (object) {
+				System.out.println("线程2开始操作");
 				System.out.println("对象object唤醒");
 				object.notify();
-				System.out.println("线程2后续操作");
 			}
 		}).start();
 	}

code/Java/java-concurrency/src/main/java/com/heibaiying/waitAndNotify/J5_NotifyAll.java

@@ -32,10 +32,11 @@ public class J5_NotifyAll {
 		}).start();
 		new Thread(() -> {
 			synchronized (object) {
+				System.out.println("线程3开始操作");
 				System.out.println("对象object唤醒");
 				// 如果是object.notify()则是随机唤醒任意一个等待
 				object.notifyAll();
-				System.out.println("线程3后续操作");
+
 			}
 		}).start();
 	}