How to implement thread scheduling and locking mechanism of Java underlying technology

How to implement the thread scheduling and locking mechanism of Java's underlying technology

In Java development, thread scheduling and locking mechanisms are very important underlying technologies. Thread scheduling refers to how the operating system allocates time slices and execution sequences to different threads, while the lock mechanism is to ensure data synchronization and mutually exclusive access among multiple threads. This article will detail how to implement these two underlying technologies and provide specific code examples.

1. Thread Scheduling
Thread scheduling is the operating system's time slice allocation and execution sequence arrangement for multi-threads. In Java, we can implement thread scheduling by using some methods provided by the Thread class.

1. Set priority
   In Java, each thread has its own priority, and the priority of the thread can be set through the setPriority() method. The priority range is 1-10, where 1 is the lowest priority and 10 is the highest priority.

The sample code is as follows:

Thread thread1 = new Thread();
thread1.setPriority(Thread.MIN_PRIORITY);

Thread thread2 = new Thread();
thread2.setPriority(Thread.NORM_PRIORITY);

Thread thread3 = new Thread();
thread3.setPriority(Thread.MAX_PRIORITY);

2. Thread sleep
   Thread sleep refers to suspending the execution of the thread for a period of time, which can be achieved through the sleep() method of the Thread class . This method accepts a number of milliseconds as a parameter, indicating how long the thread should pause execution.

The sample code is as follows:

try {
    Thread.sleep(1000); // 线程暂停执行1秒
} catch (InterruptedException e) {
    e.printStackTrace();
}

3. Thread waiting
   Thread waiting means to let one thread wait for another thread to finish executing before continuing. This can be achieved using the join() method of the Thread class.

The sample code is as follows:

Thread thread1 = new Thread();
Thread thread2 = new Thread();

// 启动线程1
thread1.start();

// 在主线程中等待线程1执行完毕
try {
    thread1.join();
} catch (InterruptedException e) {
    e.printStackTrace();
}

// 启动线程2
thread2.start();

2. Locking mechanism
In multi-threaded programming, the locking mechanism is used to protect resources shared by multiple threads to avoid concurrent access. brought about problems. Java provides the synchronized keyword and Lock interface to implement the lock mechanism.

1. synchronized keyword
   The synchronized keyword can be used to modify a method or a code block to protect access to shared resources. When a thread enters a synchronized method or code block, it acquires the lock on this object, and other threads must wait for the thread to release the lock before they can continue execution.

The sample code is as follows:

public synchronized void method() {
    // 同步代码块
    synchronized (this) {
        // 访问共享资源
    }
}

2. Lock interface
   Lock interface is another way to implement the lock mechanism provided by Java. It is more flexible than the synchronized keyword . The Lock interface provides methods such as lock(), unlock(), tryLock(), etc., which can control thread synchronization access in a more fine-grained manner.

The sample code is as follows:

Lock lock = new ReentrantLock();

lock.lock(); // 获取锁

try {
    // 访问共享资源
} finally {
    lock.unlock(); // 释放锁
}

The above is a detailed introduction on how to implement the thread scheduling and locking mechanism of Java's underlying technology. Through the above code examples, we can better understand and Use these two underlying technologies. In multi-threaded programming, reasonable use of thread scheduling and lock mechanisms can improve the efficiency and concurrency of the program. Hope this article is helpful to you.

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