checker/tests/lock/Methods.java

import org.checkerframework.checker.lock.qual.*;

public class Methods {

  final Object lock = new Object();

  @Holding("lock")
  void lockedByLock() {}

  @Holding("this")
  void lockedByThis() {}

  // unguarded calls
  void unguardedCalls() {
    // :: error: (contracts.precondition)
    lockedByLock(); // error
    // :: error: (contracts.precondition)
    lockedByThis(); // error
  }

  @Holding("lock")
  void usingHolding1() {
    lockedByLock();
    // :: error: (contracts.precondition)
    lockedByThis(); // error
  }

  @Holding("this")
  void usingHolding2() {
    // :: error: (contracts.precondition)
    lockedByLock(); // error
    lockedByThis();
  }

  void usingSynchronization1() {
    synchronized (lock) {
      lockedByLock();
      // :: error: (contracts.precondition)
      lockedByThis(); // error
    }
  }

  void usingSynchronization2() {
    synchronized (this) {
      // :: error: (contracts.precondition)
      lockedByLock(); // error
      lockedByThis();
    }
  }

  synchronized void usingMethodModifier() {
    // :: error: (contracts.precondition)
    lockedByLock(); // error
    lockedByThis();
  }
}