com.google.inject.internal.util.Collections2 Maven / Gradle / Ivy
/*
* Copyright (C) 2008 Google Inc.
*
* 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.inject.internal.util;
import java.util.Collection;
import java.util.Set;
/**
* Provides static methods for working with {@code Collection} instances.
*
* @author Chris Povirk
* @author Mike Bostock
* @author Jared Levy
*/
public final class Collections2 {
private Collections2() {}
/**
* Converts an iterable into a collection. If the iterable is already a
* collection, it is returned. Otherwise, an {@link java.util.ArrayList} is
* created with the contents of the iterable in same iteration order.
*/
static Collection toCollection(Iterable iterable) {
return (iterable instanceof Collection)
? (Collection) iterable : Lists.newArrayList(iterable);
}
static boolean setEquals(Set thisSet, @Nullable Object object) {
if (object == thisSet) {
return true;
}
if (object instanceof Set) {
Set thatSet = (Set) object;
return thisSet.size() == thatSet.size()
&& thisSet.containsAll(thatSet);
}
return false;
}
}