/*
* 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 info@exolab.org.
*
* 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 1999 (C) Intalio, Inc. All Rights Reserved.
*
* Portions of this file developed by Keith Visco after Jan 19 2005 are
* Copyright (C) 2005 Keith Visco. All Rights Reserverd.
*
* $Id$
*/
package org.exolab.castor.xml.handlers;
import java.lang.reflect.Array;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import org.exolab.castor.mapping.FieldHandler;
import org.exolab.castor.mapping.ValidityException;
/**
* A specialized FieldHandler for the XML Schema enumeration types.
*
* @author <a href="keith AT kvisco DOT com">Keith Visco</a>
* @version $Revision$ $Date: 2006-04-13 06:47:36 -0600 (Thu, 13 Apr 2006) $
*/
public class EnumFieldHandler implements FieldHandler {
/** Used to find the method "valueOf" taking an argument of type String. */
private static final Class[] STRING_ARGS = new Class[] {String.class};
/** The Factory Method name. */
private static final String METHOD_VALUEOF = "valueOf";
private static final String METHOD_FROMVALUE = "fromValue";
private static final String METHOD_VALUE = "value";
private static final String METHOD_TOSTRING = "toString";
/** The <code>valueOf(String)</code> method for the provided enumtype. */
private final Method _valueOf;
/** The field handler to which we delegate. */
private final FieldHandler _handler;
//----------------/
//- Constructors -/
//----------------/
/**
* Creates a new EnumFieldHandler with the given type and FieldHandler.
*
* @param enumType the Class type of the described field
* @param handler the FieldHandler to delegate to
*/
public EnumFieldHandler(final Class enumType, final FieldHandler handler) {
this._handler = handler;
this._valueOf = getUnmarshallMethod(enumType);
} //-- EnumFieldHandler
/**
* Reflectively finds the <code>valueOf(String)</code> method for the
* provided class type.
*
* @param type the Class for which to locate the valueOf method.
* @return the Method <code>valueOf(String)</code>
*/
private Method getUnmarshallMethod(final Class type) {
if (type == null) {
String err = "The Class argument passed to the "
+ "constructor of EnumMarshalDescriptor cannot be null.";
throw new IllegalArgumentException(err);
}
Method method = null;
// try the fromValue method to support enums with value object
try {
method = type.getMethod(METHOD_FROMVALUE, STRING_ARGS);
return method;
} catch(NoSuchMethodException exception) {
// do nothing, check valueOf
}
//
try {
method = type.getMethod(METHOD_VALUEOF, STRING_ARGS);
} catch (NoSuchMethodException nsme) {
String err = type.getName()
+ " does not contain one of the required methods public static "
+ type.getName() + " valueOf(String); " +
"or public static " + type.getName() + ".fromvalue(String value)";
throw new IllegalArgumentException(err);
}
if (!Modifier.isStatic(method.getModifiers())) {
String err = type.getName() + " public " + type.getName()
+ " valueOf(String); exists but is not static";
throw new IllegalArgumentException(err);
}
return method;
}
private Method getMarshallMethod(final Class type) {
if (type == null) {
String err = "The Class argument passed to the "
+ "constructor of EnumMarshalDescriptor cannot be null.";
throw new IllegalArgumentException(err);
}
Method method = null;
// try the value() method to support enums with value object
try {
method = type.getMethod(METHOD_VALUE, null);
return method;
} catch(NoSuchMethodException exception) {
// do nothing, use toString
}
//
try {
method = type.getMethod(METHOD_TOSTRING, null);
} catch (NoSuchMethodException nsme) {
String err = type.getName()
+ " does not contain one of the required methods value() or toString() ";
throw new IllegalArgumentException(err);
}
return method;
}
//------------------/
//- Public Methods -/
//------------------/
/**
* Returns the value of the field associated with this descriptor from the
* given target object.
*
* @param target the object to get the value from
* @return the value of the field associated with this descriptor from the
* given target object.
* @throws IllegalStateException The Java object has changed and is no
* longer supported by this handler, or the handler is not
* compatible with the Java object
*/
public Object getValue(final Object target) throws java.lang.IllegalStateException {
Object val = _handler.getValue(target);
if (val == null) {
return val;
}
Object result = null;
if (val.getClass().isArray()) {
int size = Array.getLength(val);
String[] values = new String[size];
for (int i = 0; i < size; i++) {
Object obj = Array.get(val, i);
try {
values[i] = (String) getMarshallMethod(obj.getClass()).invoke(obj, null);
} catch (Exception e) {
throw new IllegalStateException(e.toString());
}
}
result = values;
} else {
try {
result = getMarshallMethod(val.getClass()).invoke(val, null);
} catch (Exception e) {
throw new IllegalStateException(e.toString());
}
}
return result;
} //-- getValue
/**
* Sets the value of the field associated with this descriptor.
*
* @param target the object in which to set the value
* @param value the value of the field
* @throws IllegalStateException The Java object has changed and is no
* longer supported by this handler, or the handler is not
* compatible with the Java object.
*/
public void setValue(final Object target, final Object value)
throws java.lang.IllegalStateException {
Object[] args = new String[1];
Object obj = null;
if (value != null) {
args[0] = value.toString();
try {
obj = _valueOf.invoke(null, args);
} catch (java.lang.reflect.InvocationTargetException ite) {
Throwable toss = ite.getTargetException();
throw new IllegalStateException(toss.toString());
} catch (java.lang.IllegalAccessException iae) {
throw new IllegalStateException(iae.toString());
}
}
_handler.setValue(target, obj);
} //-- setValue
/**
* Sets the value of the field to a default value -- for enum, no action
* needed.
*
* @param target The object.
*/
public void resetValue(final Object target) {
// No action needed
}
/**
* Checks the field validity. Returns successfully if the field can be
* stored, is valid, etc, throws an exception otherwise.
*
* @param object The object
* @throws ValidityException The field is invalid, is required and null, or
* any other validity violation
* @throws IllegalStateException The Java object has changed and is no
* longer supported by this handler, or the handler is not
* compatiable with the Java object
*/
public void checkValidity(final Object object) throws ValidityException, IllegalStateException {
//-- do nothing for now
} //-- checkValidity
/**
* 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 "";
} //-- newInstance
/**
* Returns true if the given object is an XMLFieldHandler that is equivalent
* to the delegated handler. An equivalent XMLFieldHandler is an
* XMLFieldHandler that is an instances of the same class.
*
* @return true if the given object is an XMLFieldHandler that is equivalent
* to this one.
*/
public boolean equals(final Object obj) {
if (obj == null) {
return false;
}
if (obj == this) {
return true;
}
if (!(obj instanceof FieldHandler)) {
return false;
}
return (_handler.getClass().isInstance(obj) || getClass().isInstance(obj));
} //-- equals
} //-- EnumFieldHandler