diff options
Diffstat (limited to 'src/tools/xcode-common/java/com/google/devtools/build/xcode/util/Intersection.java')
-rw-r--r-- | src/tools/xcode-common/java/com/google/devtools/build/xcode/util/Intersection.java | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/src/tools/xcode-common/java/com/google/devtools/build/xcode/util/Intersection.java b/src/tools/xcode-common/java/com/google/devtools/build/xcode/util/Intersection.java new file mode 100644 index 0000000000..7171cdeb65 --- /dev/null +++ b/src/tools/xcode-common/java/com/google/devtools/build/xcode/util/Intersection.java @@ -0,0 +1,38 @@ +// Copyright 2014 Google Inc. All rights reserved. +// +// 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.devtools.build.xcode.util; + +import com.google.common.collect.Sets; + +import java.util.Set; + +/** + * Provides utility methods that make intersections operations type safe. + * + * {@link Sets#intersection(Set, Set)} requires no type bound on the second set, which could lead to + * calls which always return an empty set. + */ +public class Intersection { + private Intersection() { + throw new UnsupportedOperationException("static-only"); + } + + /** + * Returns the intersection of two sets. + */ + public static <T> Set<T> of(Set<T> set1, Set<T> set2) { + return Sets.intersection(set1, set2); + } +} |