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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements. See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache license, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License. You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the license for the specific language governing permissions and
15   * limitations under the license.
16   */
17  package org.apache.logging.log4j.core.util;
18  
19  import java.util.Objects;
20  
21  /**
22   * Utility class providing common validation logic.
23   */
24  public final class Assert {
25      private Assert() {
26      }
27  
28      /**
29       * Throws a {@code NullPointerException} if the specified parameter is
30       * {@code null}, otherwise returns the specified parameter.
31       * <p>
32       * On Java 7, just use {@code Objects.requireNonNull(T, String)}
33       * </p>
34       * <p>
35       * Usage:
36       * </p>
37       * <pre>
38       * // earlier you would write this:
39       * public SomeConstructor(Object param) {
40       *     if (param == null) {
41       *         throw new NullPointerException(&quot;param&quot;);
42       *     }
43       *     this.field = param;
44       * }
45       *
46       * // now you can do the same in one line:
47       * public SomeConstructor(Object param) {
48       *     this.field = Assert.requireNonNull(&quot;param&quot;);
49       * }
50       * </pre>
51       *
52       * @param <T> the type of the parameter to check and return
53       * @param object the parameter to check
54       * @param message message to populate the NPE with if necessary
55       * @return the specified parameter
56       * @throws NullPointerException if {@code object} is {@code null}
57       * @deprecated Will be removed in 2.5.
58       */
59      @Deprecated
60      public static <T> T requireNonNull(final T object, final String message) {
61          return Objects.requireNonNull(object, message);
62      }
63  }