/*

  * 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 org.apache.any23.extractor.microdata;

 /**

  * Base class for <b>Microdata</b> items.

  *

  * @author Michele Mostarda (mostarda@fbk.eu)

  */

 public abstract class Item {

     /**

      * Xpath item location in container document.

      */

     private final String xpath;

     /**

      * @return the <b>JSON</b> representation for this item.

      */

     public abstract String toJSON();

     /**

      * Constructor.

      *

      * @param xpath xpath to this item in container document.

      */

     public Item(String xpath) {

         if (xpath == null) {

             throw new NullPointerException("xpath cannot be null.");

         }

         this.xpath = xpath;

     }

     /**

      * @return the item location in container document.

      */

     public String getXpath() {

         return xpath;

     }

     @Override

     public int hashCode() {

         return xpath.hashCode();

     }

     @Override

     public boolean equals(Object obj) {

         if(obj == null) {

             return false;

         }

         if(obj == this) {

             return true;

         }

         if(obj instanceof Item) {

             final Item other = (Item) obj;

             return xpath.equals( other.xpath );

         }

         return false;

     }

 }