001 // Copyright 2007 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.hivemind.annotations.internal; 016 017 import java.lang.reflect.Method; 018 019 import org.apache.hivemind.ApplicationRuntimeException; 020 import org.apache.hivemind.Location; 021 import org.apache.hivemind.annotations.definition.Service; 022 import org.apache.hivemind.definition.ImplementationConstructionContext; 023 import org.apache.hivemind.definition.ImplementationConstructor; 024 import org.apache.hivemind.internal.AbstractServiceImplementationConstructor; 025 026 /** 027 * Constructs a service implementation by calling a factory method defined in 028 * an annotated module by use of the {@link Service} annotation. 029 * 030 * @author Achim Huegen 031 */ 032 public class MethodCallImplementationConstructor extends AbstractServiceImplementationConstructor implements 033 ImplementationConstructor 034 { 035 private Method _factoryMethod; 036 037 private ModuleInstanceProvider _moduleInstanceProvider; 038 039 public MethodCallImplementationConstructor(Location location, Method factoryMethod, 040 ModuleInstanceProvider moduleInstanceProvider) 041 { 042 super(location); 043 _factoryMethod = factoryMethod; 044 _moduleInstanceProvider = moduleInstanceProvider; 045 } 046 047 public Object constructCoreServiceImplementation(ImplementationConstructionContext context) 048 { 049 try 050 { 051 Object result = _factoryMethod.invoke(_moduleInstanceProvider.getModuleInstance(), (Object[]) null); 052 return result; 053 } 054 catch (Exception ex) 055 { 056 throw new ApplicationRuntimeException(ex.getMessage(), getLocation(), ex); 057 } 058 } 059 060 }