1   /*
2    * Copyright (C) 2011 The Guava Authors
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5    * in compliance with the License.  You may obtain a copy of the License at
6    *
7    * http://www.apache.org/licenses/LICENSE-2.0
8    *
9    * Unless required by applicable law or agreed to in writing, software distributed under the License
10   * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11   * or implied.  See the License for the specific language governing permissions and limitations
12   * under the License.
13   */
14  
15  package com.google.common.math;
16  
17  import com.google.common.annotations.GwtCompatible;
18  
19  import java.math.BigInteger;
20  
21  import javax.annotation.Nullable;
22  
23  /**
24   * A collection of preconditions for math functions.
25   *
26   * @author Louis Wasserman
27   */
28  @GwtCompatible
29  final class MathPreconditions {
30    static int checkPositive(@Nullable String role, int x) {
31      if (x <= 0) {
32        throw new IllegalArgumentException(role + " (" + x + ") must be > 0");
33      }
34      return x;
35    }
36  
37    static long checkPositive(@Nullable String role, long x) {
38      if (x <= 0) {
39        throw new IllegalArgumentException(role + " (" + x + ") must be > 0");
40      }
41      return x;
42    }
43  
44    static BigInteger checkPositive(@Nullable String role, BigInteger x) {
45      if (x.signum() <= 0) {
46        throw new IllegalArgumentException(role + " (" + x + ") must be > 0");
47      }
48      return x;
49    }
50  
51    static int checkNonNegative(@Nullable String role, int x) {
52      if (x < 0) {
53        throw new IllegalArgumentException(role + " (" + x + ") must be >= 0");
54      }
55      return x;
56    }
57  
58    static long checkNonNegative(@Nullable String role, long x) {
59      if (x < 0) {
60        throw new IllegalArgumentException(role + " (" + x + ") must be >= 0");
61      }
62      return x;
63    }
64  
65    static BigInteger checkNonNegative(@Nullable String role, BigInteger x) {
66      if (x.signum() < 0) {
67        throw new IllegalArgumentException(role + " (" + x + ") must be >= 0");
68      }
69      return x;
70    }
71  
72    static double checkNonNegative(@Nullable String role, double x) {
73      if (!(x >= 0)) { // not x < 0, to work with NaN.
74        throw new IllegalArgumentException(role + " (" + x + ") must be >= 0");
75      }
76      return x;
77    }
78  
79    static void checkRoundingUnnecessary(boolean condition) {
80      if (!condition) {
81        throw new ArithmeticException("mode was UNNECESSARY, but rounding was necessary");
82      }
83    }
84  
85    static void checkInRange(boolean condition) {
86      if (!condition) {
87        throw new ArithmeticException("not in range");
88      }
89    }
90  
91    static void checkNoOverflow(boolean condition) {
92      if (!condition) {
93        throw new ArithmeticException("overflow");
94      }
95    }
96  
97    private MathPreconditions() {}
98  }