| /* |
| * Copyright (c) 2014 Eike Stepper (Berlin, Germany) and others. |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * Eike Stepper - initial API and implementation |
| */ |
| package org.eclipse.oomph.util; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| /** |
| * @author Eike Stepper |
| */ |
| public final class Predicates |
| { |
| private Predicates() |
| { |
| } |
| |
| public static <T> Predicate<T> included(Set<T> inclusions) |
| { |
| return new IncludedPredicate<T>(inclusions); |
| } |
| |
| public static <T> Predicate<T> excluded(Set<T> exclusions) |
| { |
| return new ExcludedPredicate<T>(exclusions); |
| } |
| |
| public static <T> Predicate<T> unique() |
| { |
| return new UniquePredicate<T>(); |
| } |
| |
| @SuppressWarnings("unchecked") |
| public static <T> Predicate<T> alwaysFalse() |
| { |
| return (Predicate<T>)FalsePredicate.INSTANCE; |
| } |
| |
| @SuppressWarnings("unchecked") |
| public static <T> Predicate<T> alwaysTrue() |
| { |
| return (Predicate<T>)TruePredicate.INSTANCE; |
| } |
| |
| /** |
| * @author Eike Stepper |
| */ |
| public static final class IncludedPredicate<T> implements Predicate<T> |
| { |
| private final Set<T> inclusions; |
| |
| public IncludedPredicate(Set<T> inclusions) |
| { |
| this.inclusions = inclusions; |
| } |
| |
| public boolean apply(T element) |
| { |
| return inclusions.contains(element); |
| } |
| } |
| |
| /** |
| * @author Eike Stepper |
| */ |
| public static final class ExcludedPredicate<T> implements Predicate<T> |
| { |
| private final Set<T> exclusions; |
| |
| public ExcludedPredicate(Set<T> exclusions) |
| { |
| this.exclusions = exclusions; |
| } |
| |
| public boolean apply(T element) |
| { |
| return !exclusions.contains(element); |
| } |
| } |
| |
| /** |
| * @author Eike Stepper |
| */ |
| public static final class UniquePredicate<T> implements Predicate<T> |
| { |
| private final Set<T> applied = new HashSet<T>(); |
| |
| public boolean apply(T element) |
| { |
| return applied.add(element); |
| } |
| } |
| |
| /** |
| * @author Eike Stepper |
| */ |
| private static final class FalsePredicate implements Predicate<Object> |
| { |
| private static final Predicate<Object> INSTANCE = new FalsePredicate(); |
| |
| public boolean apply(Object element) |
| { |
| return false; |
| } |
| } |
| |
| /** |
| * @author Eike Stepper |
| */ |
| private static final class TruePredicate implements Predicate<Object> |
| { |
| private static final Predicate<Object> INSTANCE = new TruePredicate(); |
| |
| public boolean apply(Object element) |
| { |
| return true; |
| } |
| } |
| } |