1 /* 2 * Copyright (C) 2007 Google Inc. 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 com.google.common.annotations.GwtCompatible; 20 21 import javax.annotation.Nullable; 22 23 @GwtCompatible 24 interface MapConstraint<K, V> { 25 /** 26 * Throws a suitable {@code RuntimeException} if the specified key or value is 27 * illegal. Typically this is either a {@link NullPointerException}, an 28 * {@link IllegalArgumentException}, or a {@link ClassCastException}, though 29 * an application-specific exception class may be used if appropriate. 30 */ 31 void checkKeyValue(@Nullable K key, @Nullable V value); 32 33 /** 34 * Returns a brief human readable description of this constraint, such as 35 * "Not null". 36 */ 37 String toString(); 38 } 39
