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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *   http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing,
13   * software distributed under the License is distributed on an
14   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   * KIND, either express or implied.  See the License for the
16   * specific language governing permissions and limitations
17   * under the License.
18   */
19  package org.apache.maven.internal.impl;
20  
21  import java.util.Collection;
22  import java.util.List;
23  import java.util.function.Function;
24  import java.util.stream.Collectors;
25  
26  class Utils {
27      static <T> T nonNull(T t) {
28          if (t == null) {
29              throw new IllegalArgumentException();
30          }
31          return t;
32      }
33  
34      static <T> T nonNull(T t, String name) {
35          if (t == null) {
36              throw new IllegalArgumentException(name + " cannot be null");
37          }
38          return t;
39      }
40  
41      static <T> T cast(Class<T> clazz, Object o, String name) {
42          if (!clazz.isInstance(o)) {
43              if (o == null) {
44                  throw new IllegalArgumentException(name + " is null");
45              }
46              throw new IllegalArgumentException(name + " is not an instance of " + clazz.getName());
47          }
48          return clazz.cast(o);
49      }
50  
51      static <U, V> List<V> map(Collection<U> list, Function<U, V> mapper) {
52          return list.stream().map(mapper).collect(Collectors.toList());
53      }
54  }