    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.commons.collections.keyvalue;
    18
    19  import org.apache.commons.collections.KeyValue;
    20
    21  /***
    22   * Abstract pair class to assist with creating KeyValue and MapEntry implementations.
    23   *
    24   * @since Commons Collections 3.0
    25   * @version $Revision: 438363 $ $Date: 2006-08-30 05:48:00 +0100 (Wed, 30 Aug 2006) $
    26   *
    27   * @author James Strachan
    28   * @author Michael A. Smith
    29   * @author Neil O'Toole
    30   * @author Stephen Colebourne
    31   */
    32  public abstract class AbstractKeyValue implements KeyValue {
    33
    34      /*** The key */
    35      protected Object key;
    36      /*** The value */
    37      protected Object value;
    38
    39      /***
    40       * Constructs a new pair with the specified key and given value.
    41       *
    42       * @param key  the key for the entry, may be null
    43       * @param value  the value for the entry, may be null
    44       */
    45      protected AbstractKeyValue(Object key, Object value) {
    46          super();
    47          this.key = key;
    48          this.value = value;
    49      }
    50
    51      /***
    52       * Gets the key from the pair.
    53       *
    54       * @return the key
    55       */
    56      public Object getKey() {
    57          return key;
    58      }
    59
    60      /***
    61       * Gets the value from the pair.
    62       *
    63       * @return the value
    64       */
    65      public Object getValue() {
    66          return value;
    67      }
    68
    69      /***
    70       * Gets a debugging String view of the pair.
    71       *
    72       * @return a String view of the entry
    73       */
    74      public String toString() {
    75          return new StringBuffer()
    76              .append(getKey())
    77              .append('=')
    78              .append(getValue())
    79              .toString();
    80      }
    81
    82  }