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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      public static int valueIsAtLeast(final int value, final int minValue) {
29          if (value < minValue) {
30              throw new IllegalArgumentException("Value should be at least " + minValue + " but was " + value);
31          }
32          return value;
33      }
34  
35      /**
36       * Throws a {@code NullPointerException} if the specified parameter is
37       * {@code null}, otherwise returns the specified parameter.
38       * <p>
39       * On Java 7, just use {@code Objects.requireNonNull(T, String)}
40       * </p>
41       * <p>
42       * Usage:
43       * </p>
44       * <pre>
45       * // earlier you would write this:
46       * public SomeConstructor(Object param) {
47       *     if (param == null) {
48       *         throw new NullPointerException(&quot;param&quot;);
49       *     }
50       *     this.field = param;
51       * }
52       *
53       * // now you can do the same in one line:
54       * public SomeConstructor(Object param) {
55       *     this.field = Assert.requireNonNull(&quot;param&quot;);
56       * }
57       * </pre>
58       *
59       * @param <T> the type of the parameter to check and return
60       * @param object the parameter to check
61       * @param message message to populate the NPE with if necessary
62       * @return the specified parameter
63       * @throws NullPointerException if {@code object} is {@code null}
64       * @deprecated Will be removed in 2.5.
65       */
66      @Deprecated
67      public static <T> T requireNonNull(final T object, final String message) {
68          return Objects.requireNonNull(object, message);
69      }
70  }