content: /*****************************************************************
   *   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
   *
   *    https://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.cayenne.map;
  
  import java.io.Serializable;
  
  import org.apache.cayenne.configuration.ConfigurationNodeVisitor;
  import org.apache.cayenne.util.CayenneMapEntry;
  import org.apache.cayenne.util.ToStringBuilder;
  import org.apache.cayenne.util.XMLEncoder;
  import org.apache.cayenne.util.XMLSerializable;
  
  /**
   * Defines a property descriptor that is a part of an Entity. Two examples of things that
   * are described by attributes are Java class properties and database table columns.
   * 
   */
  public abstract class Attribute<E extends Entity<E, A, R>, A extends Attribute<E, A, R>, R extends Relationship<E, A, R>>
          implements CayenneMapEntry, XMLSerializable, Serializable {
  
      protected String name;
      protected Entity<E, A, R> entity;
  
      /**
       * Creates an unnamed Attribute.
       */
      public Attribute() {
      }
  
      /**
       * Creates a named Attribute.
       */
      public Attribute(String name) {
          this.name = name;
      }
  
      @Override
      public String toString() {
          return new ToStringBuilder(this).append("name", getName()).toString();
      }
  
      @Override
      public abstract void encodeAsXML(XMLEncoder encoder, ConfigurationNodeVisitor<?> delegate);
  
      /**
       * Returns parent entity that holds this attribute.
       */
      public Entity<E, A, R> getEntity() {
          return entity;
      }
  
      /**
       * Sets parent entity that holds this attribute.
       */
      public void setEntity(Entity<E, A, R> entity) {
          this.entity = entity;
      }
  
      public String getName() {
          return name;
      }
  
      public void setName(String name) {
          this.name = name;
      }
  
      public Object getParent() {
          return getEntity();
      }
  
      @SuppressWarnings("unchecked")
      public void setParent(Object parent) {
          if (parent != null && !(parent instanceof Entity)) {
              throw new IllegalArgumentException("Expected null or Entity, got: " + parent);
          }
  
          setEntity((Entity<E, A, R>) parent);
      }
  }
  