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.schema.rules; 016 017 import org.apache.hivemind.HiveMind; 018 import org.apache.hivemind.Location; 019 import org.apache.hivemind.internal.Module; 020 import org.apache.hivemind.schema.Translator; 021 022 /** 023 * Used to translate a value into a reference to a HiveMind service within the registry. 024 * 025 * @author Howard Lewis Ship 026 */ 027 public class ServiceTranslator implements Translator 028 { 029 /** 030 * Returns null if the input is null or empty. Returns the service with the given name 031 * otherwise. Will log an error and return null if an exception is thrown. If the input value is 032 * not qualified, the contributing module's id is added as a prefix. 033 */ 034 public Object translate(Module contributingModule, Class propertyType, String inputValue, 035 Location location) 036 { 037 if (HiveMind.isBlank(inputValue)) 038 return null; 039 040 return contributingModule.getService(inputValue, Object.class); 041 } 042 043 }