Scope-Based locking in Java

LockGuard.java

import java.util.concurrent.locks.Lock;

/**
 * Lock Guarding class similar to C++ lock_guard. Acquires
 * the lock on construction and releases it on close().
 */
public class LockGuard implements AutoCloseable {
  private final Lock l;
  
  public LockGuard(Lock l) {
    l.lock();
    this.l = l;
  }
  
  @Override
  public void close() {
    this.l.unlock();
  }
}

Usage.java

import java.util.concurrent.locks.ReentrantLock;

public class Usage {
  public static void main(String[] args) {
    ReentrantLock l = new ReentrantLock();
    
    // Creating a new LockGuard instances acquires the lock
    try (LockGuard guard = new LockGuard(l)) {
     System.out.println(l.isHeldByCurrentThread());
    }
    
    // Here the lock is no longer held because the guard was closed
    System.out.println(l.isHeldByCurrentThread());
  }
}