code: package edu.utexas.cs.utopia.cortado.mockclasses;
  
  import java.lang.annotation.ElementType;
  import java.lang.annotation.Retention;
  import java.lang.annotation.RetentionPolicy;
  import java.lang.annotation.Target;
  
  /**
   * Used to mark methods which are monitor invariants.
   * This method must
   * - take no parameters
   * - return a boolean
   * - throw no exceptions
   * - be private
   * - not be annotated {@link Atomic}
   */
  @Retention(RetentionPolicy.CLASS)
  @Target(ElementType.METHOD)
  public @interface MonitorInvariant
  {
  }
  