runtime/org.argeo.slc.core/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 import org.argeo.slc.execution.ExecutionSpecAttribute;
  10
  11 public class InstantiationManager {
  12
  13         private final static Log log = LogFactory
  14                         .getLog(InstantiationManager.class);
  15
  16         private ThreadLocal<Stack<ExecutionFlow>> flowStack = new ThreadLocal<Stack<ExecutionFlow>>();
  17
  18         public Object createRef(String name) {
  19
  20                 if ((flowStack.get() == null) || flowStack.get().empty()) {
  21                         throw new SlcException("No flow is currently initializing."
  22                                         + " Declare ParameterRef as inner beans or prototypes.");
  23                 }
  24
  25                 return getInitializingFlowParameter(name);
  26         }
  27
  28         public void flowInitializationStarted(ExecutionFlow flow, String flowName) {
  29                 if (log.isTraceEnabled())
  30                         log.trace("Start initialization of " + flow.hashCode() + " ("
  31                                         + flow + " - " + flow.getClass() + ")");
  32
  33                 // set the flow name if it is DefaultExecutionFlow
  34                 if (flow instanceof DefaultExecutionFlow) {
  35                         ((DefaultExecutionFlow) flow).setBeanName(flowName);
  36                 }
  37
  38                 // log.info("# flowInitializationStarted " + flowName);
  39                 // create a stack for this thread if there is none
  40                 if (flowStack.get() == null) {
  41                         flowStack.set(new Stack<ExecutionFlow>());
  42                 }
  43                 flowStack.get().push(flow);
  44         }
  45
  46         public void flowInitializationFinished(ExecutionFlow flow, String flowName) {
  47                 if (log.isTraceEnabled())
  48                         log.trace("Finish initialization of " + flow.hashCode() + " ("
  49                                         + flow + " - " + flow.getClass() + ")");
  50                 ExecutionFlow registeredFlow = flowStack.get().pop();
  51                 if (registeredFlow != null) {
  52                         if (!flow.getName().equals(registeredFlow.getName()))
  53                                 throw new SlcException("Current flow is " + flow);
  54                         // log.info("# flowInitializationFinished " + flowName);
  55                         // initializingFlow.set(null);
  56                 }
  57         }
  58
  59         protected ExecutionFlow findInitializingFlowWithParameter(String key) {
  60                 if ((flowStack.get() == null) || flowStack.get().empty())
  61                         throw new SlcException("No initializing flow available.");
  62
  63                 // first look in the outer flow (that may override parameters)
  64                 for (int i = 0; i < flowStack.get().size(); i++) {
  65                         if (flowStack.get().elementAt(i).isSetAsParameter(key)) {
  66                                 return flowStack.get().elementAt(i);
  67                         }
  68                 }
  69                 throw new SlcException("Key " + key + " is not set as parameter in "
  70                                 + flowStack.get().firstElement().toString() + " (stack size="
  71                                 + flowStack.get().size() + ")");
  72
  73         }
  74
  75         public Object getInitializingFlowParameter(String key) {
  76                 return findInitializingFlowWithParameter(key).getParameter(key);
  77         }
  78
  79         public Class<?> getInitializingFlowParameterClass(String key) {
  80                 ExecutionSpecAttribute attr = findInitializingFlowWithParameter(key)
  81                                 .getExecutionSpec().getAttributes().get(key);
  82                 if (attr instanceof RefSpecAttribute)
  83                         return ((RefSpecAttribute) attr).getTargetClass();
  84                 else if (attr instanceof PrimitiveSpecAttribute)
  85                         return ((PrimitiveSpecAttribute) attr).getTypeAsClass();
  86                 else
  87                         return null;
  88         }
  89
  90         public Boolean isInFlowInitialization() {
  91                 return (flowStack.get() != null) && !flowStack.get().empty();
  92         }
  93 }