| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package java.util; |
| |
| /** |
| * <strong>Note: Do not use this class since it is obsolete. Please use the |
| * {@link Map} interface for new implementations.</strong> |
| * <p> |
| * Dictionary is an abstract class which is the superclass of all classes that |
| * associate keys with values, such as {@code Hashtable}. |
| * |
| * @see Hashtable |
| * @since 1.0 |
| */ |
| public abstract class Dictionary<K, V> { |
| /** |
| * Constructs a new instance of this class. |
| */ |
| public Dictionary() { |
| super(); |
| } |
| |
| /** |
| * Returns an enumeration on the elements of this dictionary. |
| * |
| * @return an enumeration of the values of this dictionary. |
| * @see #keys |
| * @see #size |
| * @see Enumeration |
| */ |
| public abstract Enumeration<V> elements(); |
| |
| /** |
| * Returns the value which is associated with {@code key}. |
| * |
| * @param key |
| * the key of the value returned. |
| * @return the value associated with {@code key}, or {@code null} if the |
| * specified key does not exist. |
| * @see #put |
| */ |
| public abstract V get(Object key); |
| |
| /** |
| * Returns true if this dictionary has no key/value pairs. |
| * |
| * @return {@code true} if this dictionary has no key/value pairs, |
| * {@code false} otherwise. |
| * @see #size |
| */ |
| public abstract boolean isEmpty(); |
| |
| /** |
| * Returns an enumeration on the keys of this dictionary. |
| * |
| * @return an enumeration of the keys of this dictionary. |
| * @see #elements |
| * @see #size |
| * @see Enumeration |
| */ |
| public abstract Enumeration<K> keys(); |
| |
| /** |
| * Associate {@code key} with {@code value} in this dictionary. If {@code |
| * key} exists in the dictionary before this call, the old value in the |
| * dictionary is replaced by {@code value}. |
| * |
| * @param key |
| * the key to add. |
| * @param value |
| * the value to add. |
| * @return the old value previously associated with {@code key} or {@code |
| * null} if {@code key} is new to the dictionary. |
| * @see #elements |
| * @see #get |
| * @see #keys |
| */ |
| public abstract V put(K key, V value); |
| |
| /** |
| * Removes the key/value pair with the specified {@code key} from this |
| * dictionary. |
| * |
| * @param key |
| * the key to remove. |
| * @return the associated value before the deletion or {@code null} if |
| * {@code key} was not known to this dictionary. |
| * @see #get |
| * @see #put |
| */ |
| public abstract V remove(Object key); |
| |
| /** |
| * Returns the number of key/value pairs in this dictionary. |
| * |
| * @return the number of key/value pairs in this dictionary. |
| * @see #elements |
| * @see #keys |
| */ |
| public abstract int size(); |
| } |