https://github.com/google/guava/guava: Guava is a suite of core and expanded libraries that include utility classes, google's collections, io classes, and much much more. 
/*
 * Copyright (C) 2015 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.
 */


An API for representing graph (node and edge) data. It is analogous to the Java Collections
Framework APIs for lists, maps, sets, etc.

This package is a part of the open-source Guava
library.

/**
 * An API for representing graph (node and edge) data. It is analogous to the Java Collections
 * Framework APIs for lists, maps, sets, etc.
 *
 * <p>This package is a part of the open-source <a href="https://github.com/google/guava">Guava</a>
 * library.
 */
@CheckReturnValue
@ParametersAreNonnullByDefault
package com.google.common.graph;

import com.google.errorprone.annotations.CheckReturnValue;
import javax.annotation.ParametersAreNonnullByDefault;