Rename SLC Core into SLC Spring.

[gpl/argeo-slc.git] / org.argeo.slc.spring / src / org / argeo / slc / core / execution / InstantiationManager.java

diff --git a/org.argeo.slc.spring/src/org/argeo/slc/core/execution/InstantiationManager.java b/org.argeo.slc.spring/src/org/argeo/slc/core/execution/InstantiationManager.java
new file mode 100644 (file)
index 0000000..60e93ec
--- /dev/null
+++ b/org.argeo.slc.spring/src/org/argeo/slc/core/execution/InstantiationManager.java
@@ -0,0 +1,120 @@
+/*\r
+ * Copyright (C) 2007-2012 Argeo GmbH\r
+ *\r
+ * Licensed under the Apache License, Version 2.0 (the "License");\r
+ * you may not use this file except in compliance with the License.\r
+ * You may obtain a copy of the License at\r
+ *\r
+ *         http://www.apache.org/licenses/LICENSE-2.0\r
+ *\r
+ * Unless required by applicable law or agreed to in writing, software\r
+ * distributed under the License is distributed on an "AS IS" BASIS,\r
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
+ * See the License for the specific language governing permissions and\r
+ * limitations under the License.\r
+ */\r
+package org.argeo.slc.core.execution;\r
+\r
+import java.util.Stack;\r
+\r
+import org.apache.commons.logging.Log;\r
+import org.apache.commons.logging.LogFactory;\r
+import org.argeo.slc.SlcException;\r
+import org.argeo.slc.execution.ExecutionFlow;\r
+import org.argeo.slc.execution.ExecutionSpecAttribute;\r
+\r
+/** Manage parameters that need to be set during the instantiation of a flow */\r
+public class InstantiationManager {\r
+\r
+       private final static Log log = LogFactory\r
+                       .getLog(InstantiationManager.class);\r
+\r
+       private ThreadLocal<Stack<ExecutionFlow>> flowStack = new ThreadLocal<Stack<ExecutionFlow>>();\r
+\r
+       public Object createRef(String name) {\r
+\r
+               if ((flowStack.get() == null) || flowStack.get().empty()) {\r
+                       throw new SlcException("No flow is currently initializing."\r
+                                       + " Declare ParameterRef as inner beans or prototypes.");\r
+               }\r
+\r
+               return getInitializingFlowParameter(name);\r
+       }\r
+\r
+       public void flowInitializationStarted(ExecutionFlow flow, String flowName) {\r
+               // set the flow name if it is DefaultExecutionFlow\r
+               if (flow instanceof DefaultExecutionFlow) {\r
+                       ((DefaultExecutionFlow) flow).setBeanName(flowName);\r
+               }\r
+\r
+               if (log.isTraceEnabled())\r
+                       log.trace("Start initialization of " + flow.hashCode() + " ("\r
+                                       + flow + " - " + flow.getClass() + ")");\r
+\r
+               // log.info("# flowInitializationStarted " + flowName);\r
+               // create a stack for this thread if there is none\r
+               if (flowStack.get() == null) {\r
+                       flowStack.set(new Stack<ExecutionFlow>());\r
+               }\r
+               flowStack.get().push(flow);\r
+       }\r
+\r
+       public void flowInitializationFinished(ExecutionFlow flow, String flowName) {\r
+               if (log.isTraceEnabled())\r
+                       log.trace("Finish initialization of " + flow.hashCode() + " ("\r
+                                       + flow + " - " + flow.getClass() + ")");\r
+\r
+               if (flowStack.get() != null) {\r
+                       ExecutionFlow registeredFlow = flowStack.get().pop();\r
+                       if (registeredFlow != null) {\r
+                               if (!flow.getName().equals(registeredFlow.getName()))\r
+                                       throw new SlcException("Current flow is " + flow);\r
+                               // log.info("# flowInitializationFinished " + flowName);\r
+                               // initializingFlow.set(null);\r
+                       }\r
+               } else {\r
+                       // happens for flows imported as services\r
+                       log.warn("flowInitializationFinished - Flow Stack is null");\r
+               }\r
+       }\r
+\r
+       protected ExecutionFlow findInitializingFlowWithParameter(String key) {\r
+               if ((flowStack.get() == null) || flowStack.get().empty())\r
+                       throw new SlcException("No initializing flow available.");\r
+\r
+               // first look in the outer flow (that may override parameters)\r
+               for (int i = 0; i < flowStack.get().size(); i++) {\r
+                       if (flowStack.get().elementAt(i).isSetAsParameter(key)) {\r
+                               return flowStack.get().elementAt(i);\r
+                       }\r
+               }\r
+               throw new SlcException("Key " + key + " is not set as parameter in "\r
+                               + flowStack.get().firstElement().toString() + " (stack size="\r
+                               + flowStack.get().size() + ")");\r
+\r
+       }\r
+\r
+       public Object getInitializingFlowParameter(String key) {\r
+               return findInitializingFlowWithParameter(key).getParameter(key);\r
+       }\r
+\r
+       public Class<?> getInitializingFlowParameterClass(String key) {\r
+               ExecutionSpecAttribute attr = findInitializingFlowWithParameter(key)\r
+                               .getExecutionSpec().getAttributes().get(key);\r
+               if (attr instanceof RefSpecAttribute)\r
+                       return ((RefSpecAttribute) attr).getTargetClass();\r
+               else if (attr instanceof PrimitiveSpecAttribute) {\r
+                       String type = ((PrimitiveSpecAttribute) attr).getType();\r
+                       Class<?> clss = PrimitiveUtils.typeAsClass(type);\r
+                       if (clss == null)\r
+                               throw new SlcException("Cannot convert type " + type\r
+                                               + " to class.");\r
+                       return clss;\r
+               } else\r
+                       return null;\r
+       }\r
+\r
+       public Boolean isInFlowInitialization() {\r
+               return (flowStack.get() != null) && !flowStack.get().empty();\r
+       }\r
+}\r