AbstractSelectCriteria.java

public abstract class AbstractSelectCriteria<T, C extends SelectCriteriaImplementor<T>>
		extends AbstractNode
		implements SelectCriteriaImplementor<T> {

  @Override
  public C distinct(boolean distinct) {
    ...
    return this;
  }
    
    ...
}

JpaSelectCriteria.java

interface JpaSelectCriteria<T> ... extends javax.persistence.criteria.AbstractQuery<T>, JpaCriteriaNode {
    @Override
    JpaSelectCriteria<T> distinct(boolean distinct);

    ...
}

SelectCriteriaImplementor.java

public interface SelectCriteriaImplementor<T> extends JpaSelectCriteria<T>, CriteriaNode {

	@Override
	SelectCriteriaImplementor<T> distinct(boolean distinct);
  
  ...
}