001    // Copyright 2011 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    // http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry5.ioc.internal.util;
016    
017    import org.apache.tapestry5.ioc.Invokable;
018    
019    import java.lang.reflect.Constructor;
020    import java.lang.reflect.InvocationTargetException;
021    
022    /**
023     * Wraps the invocation of a constructor (with exception reporting) as an {@link Invokable}.
024     *
025     * @since 5.3
026     */
027    public class ConstructorInvoker<T> implements Invokable<T>
028    {
029        private final Constructor<T> constructor;
030    
031        private final Object[] constructorParameters;
032    
033        public ConstructorInvoker(Constructor constructor, Object[] constructorParameters)
034        {
035            this.constructor = constructor;
036            this.constructorParameters = constructorParameters;
037        }
038    
039        public T invoke()
040        {
041            Throwable fail;
042    
043            try
044            {
045                return constructor.newInstance(constructorParameters);
046            } catch (InvocationTargetException ex)
047            {
048                fail = ex.getTargetException();
049            } catch (Exception ex)
050            {
051                fail = ex;
052            }
053    
054            throw new RuntimeException(String.format("Error invoking constructor %s: %s",
055                    constructor, InternalUtils.toMessage(fail)), fail);
056        }
057    }