All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.exolab.castor.xml.handlers.ValueOfFieldHandler Maven / Gradle / Ivy

/*
 * Redistribution and use of this software and associated documentation ("Software"), with or
 * without modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions
 * must also contain a copy of this document.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided with
 * the distribution.
 *
 * 3. The name "Exolab" must not be used to endorse or promote products derived from this Software
 * without prior written permission of Intalio, Inc. For written permission, please contact
 * [email protected].
 *
 * 4. Products derived from this Software may not be called "Exolab" nor may "Exolab" appear in
 * their names without prior written permission of Intalio, Inc. Exolab is a registered trademark of
 * Intalio, Inc.
 *
 * 5. Due credit should be given to the Exolab Project (http://www.exolab.org/).
 *
 * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTALIO, INC. OR ITS
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 2004 (C) Intalio, Inc. All Rights Reserved.
 *
 * $Id$
 */
package org.exolab.castor.xml.handlers;

import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

import org.exolab.castor.mapping.FieldDescriptor;
import org.exolab.castor.mapping.FieldHandler;
import org.exolab.castor.mapping.GeneralizedFieldHandler;
import org.exolab.castor.mapping.MappingException;

/**
 * An implementation of GeneralizedFieldHandler for classes that have a built-in valueOf(String)
 * factory method, such as type-safe enumeration classes, java.sql.Timestamp, etc.
 *
 * @author Keith Visco
 * @version $Revision$ $Date: 2006-04-14 04:14:43 -0600 (Fri, 14 Apr 2006) $
 * @see FieldDescriptor
 * @see FieldHandler
 */
public class ValueOfFieldHandler extends GeneralizedFieldHandler {

  /** The Class[] holding the argument types of the factory method. */
  private static final Class[] ARGS = new Class[] {String.class};
  /** The Factory Method name. */
  private static final String METHOD_NAME = "valueOf";

  /** The class type for this FieldHandler. */
  private final Class _type;
  /** The valueOf method reference. */
  private final Method _valueOf;

  /**
   * Creates a new ValueOfFieldHandler.
   *
   * @param type the class type to create the FieldHandler for
   * @throws MappingException if the valueOf method cannot be found
   */
  public ValueOfFieldHandler(final Class type) throws MappingException {
    super();
    if (type == null) {
      throw new IllegalArgumentException("The argument 'type' must not be null.");
    }

    _type = type;

    Method method = null;
    try {
      method = type.getMethod(METHOD_NAME, ARGS);
    } catch (java.lang.NoSuchMethodException nsme) {
      throw new MappingException(nsme);
    }
    if (!Modifier.isStatic(method.getModifiers())) {
      String err = "No static method '" + METHOD_NAME + "' found in class: " + type.getName();
      throw new MappingException(err);
    }

    _valueOf = method;
  } // -- ValueOfFieldHandler

  /**
   * This method is used to convert the value when the getValue method is called. The getValue
   * method will obtain the actual field value from given 'parent' object. This convert method is
   * then invoked with the field's value. The value returned from this method will be the actual
   * value returned by getValue method.
   *
   * @param value the object value to convert after performing a get operation
   * @return the converted value.
   */
  public Object convertUponGet(final Object value) {
    // -- no conversion necessary for marshaling
    return value;
  } // -- convertUponGet

  /**
   * This method is used to convert the value when the setValue method is called. The setValue
   * method will call this method to obtain the converted value. The converted value will then be
   * used as the value to set for the field.
   *
   * @param value the object value to convert before performing a set operation
   * @return the converted value.
   */
  public Object convertUponSet(final Object value) {
    Object[] args = new Object[1];

    if (value != null) {
      args[0] = value.toString();
    }

    Object result = null;

    try {
      result = _valueOf.invoke(null, args);
    } catch (java.lang.IllegalAccessException iae) {
      throw new IllegalStateException(iae.getMessage());
    } catch (java.lang.reflect.InvocationTargetException ite) {
      throw new IllegalStateException(ite.getMessage());
    }

    return result;
  } // -- convertUponSet;

  /**
   * Returns the class type for the field that this GeneralizedFieldHandler converts to and from.
   * This should be the type that is used in the object model.
   *
   * @return the class type of of the field
   */
  public Class getFieldType() {
    return _type;
  } // -- getFieldType

  /**
   * Creates a new instance of the object described by this field.
   *
   * @param parent The object for which the field is created
   * @return A new instance of the field's value
   * @throws IllegalStateException This field is a simple type and cannot be instantiated
   */
  public Object newInstance(final Object parent) throws IllegalStateException {
    return null;
  }

} // -- ValueOfFieldHandler




© 2015 - 2024 Weber Informatics LLC | Privacy Policy