runtime/org.argeo.slc.support.simple/src/main/java/org/argeo/slc/core/execution/InstantiationManager.java

   1 package org.argeo.slc.core.execution;
   2
   3 import java.util.Stack;
   4
   5 import org.apache.commons.logging.Log;
   6 import org.apache.commons.logging.LogFactory;
   7 import org.argeo.slc.SlcException;
   8 import org.argeo.slc.execution.ExecutionFlow;
   9
  10 public class InstantiationManager {
  11
  12         private final static Log log = LogFactory.getLog(InstantiationManager.class);
  13
  14         private ThreadLocal<Stack<ExecutionFlow> > flowStack = new ThreadLocal<Stack<ExecutionFlow> >();
  15
  16         public Object createRef(String name) {
  17
  18                 if((flowStack.get() == null) ||  flowStack.get().empty()) {
  19                         throw new SlcException("No flow is currently initializing."
  20                                         + " Declare ParameterRef as inner beans or prototypes.");
  21                 }
  22
  23                 return getInitializingFlowParameter(name);
  24         }
  25
  26         public void flowInitializationStarted(ExecutionFlow flow, String flowName) {
  27                 if (log.isTraceEnabled())
  28                         log.trace("Start initialization of " + flow.hashCode() + " ("
  29                                         + flow + " - " + flow.getClass() + ")");
  30
  31                 // set the flow name if it is DefaultExecutionFlow
  32                 if(flow instanceof DefaultExecutionFlow) {
  33                         ((DefaultExecutionFlow) flow).setBeanName(flowName);
  34                 }
  35
  36 //              log.info("# flowInitializationStarted " + flowName);
  37                 // create a stack for this thread if there is none
  38                 if(flowStack.get() == null) {
  39                         flowStack.set(new Stack<ExecutionFlow>());
  40                 }
  41                 flowStack.get().push(flow);
  42         }
  43
  44         public void flowInitializationFinished(ExecutionFlow flow, String flowName) {
  45                 if (log.isTraceEnabled())
  46                         log.trace("Finish initialization of " + flow.hashCode() + " ("
  47                                         + flow + " - " + flow.getClass() + ")");
  48                 ExecutionFlow registeredFlow = flowStack.get().pop();
  49                 if (registeredFlow != null) {
  50                         if (!flow.getName().equals(registeredFlow.getName()))
  51                                 throw new SlcException("Current flow is " + flow);
  52 //                      log.info("# flowInitializationFinished " + flowName);
  53 //                      initializingFlow.set(null);
  54                 }
  55         }
  56
  57         public Object getInitializingFlowParameter(String key) {
  58                 if ((flowStack.get() == null) || flowStack.get().empty())
  59                         throw new SlcException("No initializing flow available.");
  60
  61                 // first look in the outer flow (that may override parameters)
  62                 for(int i = 0; i < flowStack.get().size(); i++) {
  63                         if(flowStack.get().elementAt(i).isSetAsParameter(key)) {
  64                                 return flowStack.get().elementAt(i).getParameter(key);
  65                         }
  66                 }
  67                 throw new SlcException("Key " + key + " is not set as parameter in "
  68                                 + flowStack.get().firstElement().toString() + " (stack size="+flowStack.get().size()+")");
  69         }
  70
  71         public Boolean isInFlowInitialization() {
  72                 return (flowStack.get() != null) && !flowStack.get().empty();
  73         }
  74 }