com.google.common.collect.CompoundOrdering Maven / Gradle / Ivy
/*
* Copyright (C) 2007 The Guava Authors
*
* 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.common.collect;
import com.google.common.annotations.GwtCompatible;
import java.io.Serializable;
import java.util.Comparator;
/** An ordering that tries several comparators in order. */
@GwtCompatible(serializable = true)
final class CompoundOrdering extends Ordering implements Serializable {
final ImmutableList> comparators;
CompoundOrdering(Comparator primary,
Comparator secondary) {
this.comparators
= ImmutableList.>of(primary, secondary);
}
CompoundOrdering(Iterable> comparators) {
this.comparators = ImmutableList.copyOf(comparators);
}
@Override public int compare(T left, T right) {
// Avoid using the Iterator to avoid generating garbage (issue 979).
int size = comparators.size();
for (int i = 0; i < size; i++) {
int result = comparators.get(i).compare(left, right);
if (result != 0) {
return result;
}
}
return 0;
}
@Override public boolean equals(Object object) {
if (object == this) {
return true;
}
if (object instanceof CompoundOrdering) {
CompoundOrdering that = (CompoundOrdering) object;
return this.comparators.equals(that.comparators);
}
return false;
}
@Override public int hashCode() {
return comparators.hashCode();
}
@Override public String toString() {
return "Ordering.compound(" + comparators + ")";
}
private static final long serialVersionUID = 0;
}