| // Copyright (C) 2009 The Android Open Source Project |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package com.google.gerrit.server.query; |
| |
| import com.google.gwtorm.client.OrmException; |
| |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.List; |
| |
| /** Negates the result of another predicate. */ |
| public class NotPredicate<T> extends Predicate<T> { |
| private final Predicate<T> that; |
| |
| protected NotPredicate(final Predicate<T> that) { |
| if (that instanceof NotPredicate) { |
| throw new IllegalArgumentException("Double negation unsupported"); |
| } |
| this.that = that; |
| } |
| |
| @Override |
| public final List<Predicate<T>> getChildren() { |
| return Collections.singletonList(that); |
| } |
| |
| @Override |
| public final int getChildCount() { |
| return 1; |
| } |
| |
| @Override |
| public final Predicate<T> getChild(final int i) { |
| if (i != 0) { |
| throw new ArrayIndexOutOfBoundsException(i); |
| } |
| return that; |
| } |
| |
| @Override |
| public Predicate<T> copy(final Collection<? extends Predicate<T>> children) { |
| if (children.size() != 1) { |
| throw new IllegalArgumentException("Expected exactly one child"); |
| } |
| return new NotPredicate<T>(children.iterator().next()); |
| } |
| |
| @Override |
| public boolean match(final T object) throws OrmException { |
| return !that.match(object); |
| } |
| |
| @Override |
| public int getCost() { |
| return that.getCost(); |
| } |
| |
| @Override |
| public int hashCode() { |
| return ~that.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(final Object other) { |
| if (other == null) |
| return false; |
| return getClass() == other.getClass() |
| && getChildren().equals(((Predicate<?>) other).getChildren()); |
| } |
| |
| @Override |
| public final String toString() { |
| return "-" + that.toString(); |
| } |
| } |