001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.wicket.proxy.objenesis;
018
019import org.apache.wicket.WicketRuntimeException;
020import org.apache.wicket.util.lang.Classes;
021
022/**
023 * Instantiator for Objects without default constructor.
024 */
025@FunctionalInterface
026public interface IInstantiator
027{
028        /**
029         * Create a new instance.
030         * 
031         * @param type
032         *            type of instance
033         * @return instance
034         */
035        <T> T newInstance(Class<T> type);
036
037        static IInstantiator getInstantiator()
038        {
039                try
040                {
041                        return new ObjenesisInstantiator();
042                }
043                catch (NoClassDefFoundError e)
044                {
045                        return new IInstantiator()
046                        {
047                                @Override
048                                public <T> T newInstance(Class<T> type)
049                                {
050                                        throw new WicketRuntimeException(String.format(
051                                                        "Can't create proxy for %s without default constructor"
052                                                                        + " - you can remedy this by adding Objenesis to your project dependencies.",
053                                                        Classes.name(type)));
054                                }
055                        };
056                }
057        }
058}