runtime/org.argeo.slc.core/src/main/java/org/argeo/slc/core/execution/ParameterRef.java

   1 /*
   2  * Copyright (C) 2007-2012 Argeo GmbH
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package org.argeo.slc.core.execution;
  17
  18 import org.apache.commons.logging.Log;
  19 import org.apache.commons.logging.LogFactory;
  20 import org.springframework.beans.factory.FactoryBean;
  21
  22 public class ParameterRef implements FactoryBean {
  23         private final static Log log = LogFactory.getLog(ParameterRef.class);
  24
  25         private InstantiationManager instantiationManager;
  26         private String name;
  27
  28         /** Cached object. */
  29         private Object object;
  30
  31         public ParameterRef() {
  32         }
  33
  34         public ParameterRef(String name) {
  35                 this.name = name;
  36         }
  37
  38         public Object getObject() throws Exception {
  39                 if (log.isTraceEnabled())
  40                         log.debug("Parameter ref called for " + name);
  41
  42                 if (object == null)
  43                         object = instantiationManager.getInitializingFlowParameter(name);
  44                 return object;
  45         }
  46
  47         public Class<?> getObjectType() {
  48                 if (object == null)
  49                         return instantiationManager.getInitializingFlowParameterClass(name);
  50                 else
  51                         return object.getClass();
  52         }
  53
  54         public boolean isSingleton() {
  55                 return true;
  56         }
  57
  58         public void setInstantiationManager(
  59                         InstantiationManager instantiationManager) {
  60                 this.instantiationManager = instantiationManager;
  61         }
  62
  63         public void setName(String name) {
  64                 this.name = name;
  65         }
  66
  67 }