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Utility classes for Jetty
//========================================================================
//Copyright 2004-2008 Mort Bay Consulting Pty. Ltd.
//------------------------------------------------------------------------
//Licensed 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.mortbay.util.ajax;
import java.lang.reflect.Method;
import java.util.Map;
import org.mortbay.log.Log;
import org.mortbay.util.Loader;
import org.mortbay.util.ajax.JSON.Output;
/* ------------------------------------------------------------ */
/**
* Convert an {@link Enum} to JSON.
* If fromJSON is true in the constructor, the JSON generated will
* be of the form {class="com.acme.TrafficLight",value="Green"}
* If fromJSON is false, then only the string value of the enum is generated.
* @author gregw
*
*/
public class JSONEnumConvertor implements JSON.Convertor
{
private boolean _fromJSON;
private Method _valueOf;
{
try
{
Class e = Loader.loadClass(getClass(),"java.lang.Enum");
_valueOf=e.getMethod("valueOf",new Class[]{Class.class,String.class});
}
catch(Exception e)
{
throw new RuntimeException("!Enums",e);
}
}
public JSONEnumConvertor()
{
this(false);
}
public JSONEnumConvertor(boolean fromJSON)
{
_fromJSON=fromJSON;
}
public Object fromJSON(Map map)
{
if (!_fromJSON)
throw new UnsupportedOperationException();
try
{
Class c=Loader.loadClass(getClass(),(String)map.get("class"));
return _valueOf.invoke(null,new Object[]{c,map.get("value")});
}
catch(Exception e)
{
Log.warn(e);
}
return null;
}
public void toJSON(Object obj, Output out)
{
if (_fromJSON)
{
out.addClass(obj.getClass());
out.add("value",obj.toString());
}
else
{
out.add(obj.toString());
}
}
}