How is thread safety implemented in Java functions?

The implementation methods of thread-safe functions in Java are: locking (Synchronized keyword): Use the synchronized keyword to modify the method to ensure that only one thread executes the method at the same time to prevent data competition. Immutable objects: If the object a function operates on is immutable, it is inherently thread-safe. Atomic operations (Atomic class): Use thread-safe atomic operations provided by atomic classes such as AtomicInteger to operate on basic types, and use the underlying lock mechanism to ensure the atomicity of the operation.

Thread-safe function implementation in Java

In a multi-threaded environment, in order to prevent data competition and errors, ensure that the function Thread safety is crucial. Java provides a variety of methods to achieve thread safety of functions:

1. Locking (Synchronized keyword)

public class Counter {
    private int count;

    public synchronized void increment() {
        count++;
    }

    public synchronized int getCount() {
        return count;
    }
}

Use synchronized key Word-modified methods ensure that only one thread executes the method at a time, thereby preventing data races.

2. Immutable objects

If the object operated by a function is immutable, then it is inherently thread-safe. Immutable objects include basic types such as String, Integer, and BigDecimal.

public class ImmutableCounter {
    private final int count;

    public ImmutableCounter(int count) {
        this.count = count;
    }

    public int getCount() {
        return count;
    }
}

3. Atomic operations (Atomic class) Atomic classes such as

AtomicInteger provide thread-safe atomic operations to operate on basic types. These classes use an underlying locking mechanism to ensure atomicity of operations.

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

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

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

Practical case: Shared counter

Suppose we have a shared counter, and multiple threads need to increase and obtain its value concurrently:

public class SharedCounter {

    // 使用原子操作来确保线程安全的计数操作
    private AtomicInteger count = new AtomicInteger(0);

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

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

Using this shared counter, multiple threads can safely increment and obtain its value concurrently without worrying about data races.

The above is the detailed content of How is thread safety implemented in Java functions?. For more information, please follow other related articles on the PHP Chinese website!