JAVA underlying concurrent programming practical skills

JAVA low-level concurrent programming practical skills, specific code examples are required

Abstract: With the popularity of multi-core processors, multi-threaded concurrent programming has become an issue that cannot be ignored in development a part of. However, Java concurrent programming is not just about using the keyword synchronized or using thread pools. The underlying concurrent programming is also important content that we need to understand. This article will introduce several common JAVA low-level concurrent programming practical techniques, and provide specific code examples to help readers better understand and apply these techniques.

1. Use the Atomic class to implement thread-safe counters

The Atomic class is an atomic operation class provided in the Java concurrency package, which can ensure that the operation of variables is atomic. , that is, there will be no thread safety issues when accessed by multiple threads. The following example shows how to use the AtomicInteger class to implement a thread-safe counter:

import java.util.concurrent.atomic.AtomicInteger;

public class Counter {
    private AtomicInteger count = new AtomicInteger(0);

    public void increment() {
        count.incrementAndGet();
    }

    public int getCount() {
        return count.get();
    }
}

2. Use the Lock interface to achieve precisely controlled synchronization

Compared with the keyword synchronized, The Lock interface provides a more flexible and controllable synchronization mechanism. The following example shows how to use the ReentrantLock class to achieve precisely controlled synchronization:

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class SyncExample {
    private Lock lock = new ReentrantLock();
    private int count = 0;

    public void increment() {
        lock.lock();
        try {
            count++;
        } finally {
            lock.unlock();
        }
    }

    public int getCount() {
        return count;
    }
}

3. Use the Condition interface to implement communication between threads

The Condition interface is the basis provided by the Lock interface A mechanism for inter-thread communication that allows threads to wait for specific conditions to occur and perform corresponding operations. The following example shows how to use the Condition interface to implement communication between threads:

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public class Worker {
    private Lock lock = new ReentrantLock();
    private Condition condition = lock.newCondition();
    private boolean flag = false;

    public void work() {
        lock.lock();
        try {
            while (!flag) {
                condition.await();
            }
            // 条件满足后执行工作
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        } finally {
            lock.unlock();
        }
    }

    public void changeFlag() {
        lock.lock();
        try {
            flag = true;
            condition.signalAll();
        } finally {
            lock.unlock();
        }
    }
}

Conclusion: This article introduces several practical techniques for JAVA's underlying concurrent programming and provides specific code examples. By learning and applying these techniques, we can better utilize the performance of multi-core processors and improve the concurrency and efficiency of our programs. At the same time, we should also pay attention to precautions in concurrent programming, such as avoiding deadlocks, race conditions and other issues. I hope this article can be helpful to readers and apply relevant concurrent programming skills in actual development.

The above is the detailed content of JAVA underlying concurrent programming practical skills. For more information, please follow other related articles on the PHP Chinese website!