com.greenpepper.util.Factory Maven / Gradle / Ivy
/*
* Copyright (c) 2007 Pyxis Technologies inc.
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA,
* or see the FSF site: http://www.fsf.org.
*/
package com.greenpepper.util;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
/**
* Factory class.
*
* @author oaouattara
* @version $Id: $Id
*/
public class Factory
{
private final Class type;
private final Method factoryMethod;
/**
* Constructor for Factory.
*
* @param type a {@link java.lang.Class} object.
*/
public Factory(Class type)
{
this.type = type;
this.factoryMethod = factoryMethod();
if (factoryMethod == null) throw new IllegalArgumentException(type.getName());
}
/**
* newInstance.
*
* @param args a {@link java.lang.Object} object.
* @return a T object.
*/
public T newInstance(Object... args)
{
try
{
return type.cast(factoryMethod.invoke(null, args));
}
catch (IllegalAccessException e)
{
throw ExceptionImposter.imposterize( e );
}
catch (InvocationTargetException e)
{
throw ExceptionImposter.imposterize( e.getCause() );
}
}
private Method factoryMethod()
{
for (Method method : type.getMethods())
{
if (
ClassUtils.isPublic(method) &&
ClassUtils.isStatic(method) &&
type.isAssignableFrom(method.getReturnType()) &&
(method.getName().equals("newInstance") || method.getAnnotation(FactoryMethod.class) != null)
)
return method;
}
return null;
}
}