Java tutorial
/* * ************************************************************************************* * Copyright (C) 2008 EsperTech, Inc. All rights reserved. * * http://esper.codehaus.org * * http://www.espertech.com * * ---------------------------------------------------------------------------------- * * The software in this package is published under the terms of the GPL license * * a copy of which has been included with this distribution in the license.txt file. * * ************************************************************************************* */ package com.espertech.esper.event.bean; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.lang.reflect.Constructor; import java.lang.reflect.InvocationTargetException; public class BeanInstantiatorByCtor implements BeanInstantiator { private static Log log = LogFactory.getLog(BeanInstantiatorByCtor.class); private final Constructor ctor; public BeanInstantiatorByCtor(Constructor ctor) { this.ctor = ctor; } public Object instantiate() { try { return ctor.newInstance(); } catch (InvocationTargetException e) { String message = "Unexpected exception encountered invoking constructor '" + ctor.getName() + "' on class '" + ctor.getDeclaringClass().getName() + "': " + e.getTargetException().getMessage(); log.error(message, e); return null; } catch (IllegalAccessException ex) { return handle(ex); } catch (InstantiationException ex) { return handle(ex); } } private Object handle(Exception e) { String message = "Unexpected exception encountered invoking newInstance on class '" + ctor.getDeclaringClass().getName() + "': " + e.getMessage(); log.error(message, e); return null; } }