| // 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; |
| |
| /** |
| * Holds another predicate in a named variable. |
| * |
| * @see QueryRewriter |
| */ |
| public class VariablePredicate<T> extends Predicate<T> { |
| private final String name; |
| private final Predicate<T> that; |
| |
| protected VariablePredicate(final String name, final Predicate<T> that) { |
| this.name = name; |
| this.that = that; |
| } |
| |
| public String getName() { |
| return name; |
| } |
| |
| @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 VariablePredicate<T>(getName(), 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 getName().hashCode() * 31 + that.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(final Object other) { |
| if (getClass() == other.getClass()) { |
| final VariablePredicate<?> v = (VariablePredicate<?>) other; |
| return getName().equals(v.getName()) |
| && getChildren().equals(v.getChildren()); |
| } |
| return false; |
| } |
| |
| @Override |
| public final String toString() { |
| return getName() + "=(" + that.toString() + ")"; |
| } |
| } |