com.ajjpj.afoundation.collection.immutable.ASet Maven / Gradle / Ivy
package com.ajjpj.afoundation.collection.immutable;
import com.ajjpj.afoundation.collection.AEquality;
import com.ajjpj.afoundation.function.AFunction1;
import com.ajjpj.afoundation.function.APartialFunction;
import com.ajjpj.afoundation.function.APredicate;
/**
* This interface represents an immutable set. It inherits most methods from ACollection, but it
* prescribes uniqueness semantics.
*
* Implementations of {@link ACollection#map(com.ajjpj.afoundation.function.AFunction1)} and
* {@link ACollection#flatMap(com.ajjpj.afoundation.function.AFunction1)} do not
* return instances of {@code ASet}, but rather generic collections without uniqueness guarantees. If {@code ASet} semantics are
* required, call {@link ACollection#toSet()} on the results.
*
* @author arno
*/
public interface ASet extends ACollection {
@Override ASet filter(APredicate pred) throws E;
@Override ASet map(AFunction1 f) throws E;
@Override ASet flatMap(AFunction1, E> f) throws E;
@Override ASet collect (APartialFunction pf) throws E;
@Override ASet flatten ();
/**
* @return the specification of equality on which this set maintains uniqueness.
* {@link com.ajjpj.afoundation.collection.AEquality#EQUALS} uses {@link Object#equals(Object)}
* and represents the 'normal' equality used by {@link java.util.Set}.
*/
AEquality equalityForEquals();
/**
* @return a {@link java.util.Set} 'view' of this set's values, i.e. an read-only instance
* of {@link java.util.Set} that contains the exact same elements as this {@code ASet}.
* This operation performs no copying, and the returned collection is based
* on this {@code ASet}'s equality.
*/
java.util.Set asJavaUtilSet();
/**
* @return a new {@link ASet} that is guaranteed to contain the new element, i.e. to contain an
* element which this set's {@link com.ajjpj.afoundation.collection.AEquality} considers
* equal to the parameter {@code el}.
*/
ASet added (T el);
/**
* @return a new {@link ASet} that is guaranteed not to contain the parameter {@code el}, i.e. not
* to contain an element that this set's {@link com.ajjpj.afoundation.collection.AEquality}
* considers equal to the parameter {@code el}.
*/
ASet removed (T el);
}