001 // Copyright 2004, 2005 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.service.impl; 016 017 import org.apache.hivemind.ApplicationRuntimeException; 018 import org.apache.hivemind.Location; 019 import org.apache.hivemind.internal.Module; 020 import org.apache.hivemind.service.ObjectProvider; 021 import org.apache.hivemind.util.PropertyUtils; 022 023 /** 024 * {@link org.apache.hivemind.service.ObjectProvider} implementation 025 * that obtains a named property from a service. This provider is 026 * mapped to the prefix "service-property", the service id is seperated 027 * from the property name by a colon. Example: 028 * <code>service-property:MyService:myProperty</code> 029 * 030 * @author Howard Lewis Ship 031 */ 032 public class ServicePropertyObjectProvider implements ObjectProvider 033 { 034 035 public Object provideObject( 036 Module contributingModule, 037 Class propertyType, 038 String locator, 039 Location location) 040 { 041 int commax = locator.indexOf(':'); 042 043 if (commax < 2) 044 { 045 throw new ApplicationRuntimeException( 046 ServiceMessages.invalidServicePropertyLocator(locator), 047 location, 048 null); 049 } 050 051 String serviceId = locator.substring(0, commax); 052 String propertyName = locator.substring(commax + 1); 053 054 Object service = contributingModule.getService(serviceId, Object.class); 055 056 return PropertyUtils.read(service, propertyName); 057 } 058 059 }