Coverage Summary for Class: CollectPreconditions (com.google.common.collect)

1 /*
2  * Copyright (C) 2008 The Guava Authors
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  * http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.google.common.collect;
18 
19 import static com.google.common.base.Preconditions.checkState;
20 
21 import com.google.common.annotations.GwtCompatible;
22 import com.google.errorprone.annotations.CanIgnoreReturnValue;
23 
24 /** Precondition checks useful in collection implementations. */
25 @GwtCompatible
26 final class CollectPreconditions {
27 
28   static void checkEntryNotNull(Object key, Object value) {
29     if (key == null) {
30       throw new NullPointerException("null key in entry: null=" + value);
31     } else if (value == null) {
32       throw new NullPointerException("null value in entry: " + key + "=null");
33     }
34   }
35 
36   @CanIgnoreReturnValue
37   static int checkNonnegative(int value, String name) {
38     if (value < 0) {
39       throw new IllegalArgumentException(name + " cannot be negative but was: " + value);
40     }
41     return value;
42   }
43 
44   @CanIgnoreReturnValue
45   static long checkNonnegative(long value, String name) {
46     if (value < 0) {
47       throw new IllegalArgumentException(name + " cannot be negative but was: " + value);
48     }
49     return value;
50   }
51 
52   static void checkPositive(int value, String name) {
53     if (value <= 0) {
54       throw new IllegalArgumentException(name + " must be positive but was: " + value);
55     }
56   }
57 
58   /**
59    * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
60    * error message.
61    */
62   static void checkRemove(boolean canRemove) {
63     checkState(canRemove, "no calls to next() since the last call to remove()");
64   }
65 }