Clarify SLC project structure.

[gpl/argeo-slc.git] / cms / org.argeo.slc.runtime / src / org / argeo / slc / runtime / InstantiationManager.java

diff --git a/cms/org.argeo.slc.runtime/src/org/argeo/slc/runtime/InstantiationManager.java b/cms/org.argeo.slc.runtime/src/org/argeo/slc/runtime/InstantiationManager.java
new file mode 100644 (file)
index 0000000..4aea94f
--- /dev/null
+++ b/cms/org.argeo.slc.runtime/src/org/argeo/slc/runtime/InstantiationManager.java
@@ -0,0 +1,108 @@
+package org.argeo.slc.runtime;
+
+import java.util.Stack;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.argeo.slc.SlcException;
+import org.argeo.slc.execution.ExecutionFlow;
+import org.argeo.slc.execution.ExecutionSpecAttribute;
+import org.argeo.slc.execution.RefSpecAttribute;
+import org.argeo.slc.primitive.PrimitiveSpecAttribute;
+import org.argeo.slc.primitive.PrimitiveUtils;
+
+/** Manage parameters that need to be set during the instantiation of a flow */
+public class InstantiationManager {
+
+       private final static Log log = LogFactory
+                       .getLog(InstantiationManager.class);
+
+       private ThreadLocal<Stack<ExecutionFlow>> flowStack = new ThreadLocal<Stack<ExecutionFlow>>();
+
+       public Object createRef(String name) {
+
+               if ((flowStack.get() == null) || flowStack.get().empty()) {
+                       throw new SlcException("No flow is currently initializing."
+                                       + " Declare ParameterRef as inner beans or prototypes.");
+               }
+
+               return getInitializingFlowParameter(name);
+       }
+
+       public void flowInitializationStarted(ExecutionFlow flow, String flowName) {
+               // set the flow name if it is DefaultExecutionFlow
+               if (flow instanceof DefaultExecutionFlow) {
+                       ((DefaultExecutionFlow) flow).setName(flowName);
+               }
+
+               if (log.isTraceEnabled())
+                       log.trace("Start initialization of " + flow.hashCode() + " ("
+                                       + flow + " - " + flow.getClass() + ")");
+
+               // log.info("# flowInitializationStarted " + flowName);
+               // create a stack for this thread if there is none
+               if (flowStack.get() == null) {
+                       flowStack.set(new Stack<ExecutionFlow>());
+               }
+               flowStack.get().push(flow);
+       }
+
+       public void flowInitializationFinished(ExecutionFlow flow, String flowName) {
+               if (log.isTraceEnabled())
+                       log.trace("Finish initialization of " + flow.hashCode() + " ("
+                                       + flow + " - " + flow.getClass() + ")");
+
+               if (flowStack.get() != null) {
+                       ExecutionFlow registeredFlow = flowStack.get().pop();
+                       if (registeredFlow != null) {
+                               if (!flow.getName().equals(registeredFlow.getName()))
+                                       throw new SlcException("Current flow is " + flow);
+                               // log.info("# flowInitializationFinished " + flowName);
+                               // initializingFlow.set(null);
+                       }
+               } else {
+                       // happens for flows imported as services
+                       log.warn("flowInitializationFinished - Flow Stack is null");
+               }
+       }
+
+       protected ExecutionFlow findInitializingFlowWithParameter(String key) {
+               if ((flowStack.get() == null) || flowStack.get().empty())
+                       throw new SlcException("No initializing flow available.");
+
+               // first look in the outer flow (that may override parameters)
+               for (int i = 0; i < flowStack.get().size(); i++) {
+                       if (flowStack.get().elementAt(i).isSetAsParameter(key)) {
+                               return flowStack.get().elementAt(i);
+                       }
+               }
+               throw new SlcException("Key " + key + " is not set as parameter in "
+                               + flowStack.get().firstElement().toString() + " (stack size="
+                               + flowStack.get().size() + ")");
+
+       }
+
+       public Object getInitializingFlowParameter(String key) {
+               return findInitializingFlowWithParameter(key).getParameter(key);
+       }
+
+       public Class<?> getInitializingFlowParameterClass(String key) {
+               ExecutionSpecAttribute attr = findInitializingFlowWithParameter(key)
+                               .getExecutionSpec().getAttributes().get(key);
+               if (attr instanceof RefSpecAttribute)
+                       return ((RefSpecAttribute) attr).getTargetClass();
+               else if (attr instanceof PrimitiveSpecAttribute) {
+                       String type = ((PrimitiveSpecAttribute) attr).getType();
+                       Class<?> clss = PrimitiveUtils.typeAsClass(type);
+                       if (clss == null)
+                               throw new SlcException("Cannot convert type " + type
+                                               + " to class.");
+                       return clss;
+               } else
+                       return null;
+       }
+
+       public Boolean isInFlowInitialization() {
+               return (flowStack.get() != null) && !flowStack.get().empty();
+       }
+}