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

   1 package org.argeo.slc.core.execution;
   2
   3 import org.apache.commons.logging.Log;
   4 import org.apache.commons.logging.LogFactory;
   5 import org.argeo.slc.execution.ExecutionContext;
   6 import org.argeo.slc.execution.ExecutionFlow;
   7 import org.argeo.slc.execution.ExecutionStack;
   8 import org.aspectj.lang.ProceedingJoinPoint;
   9 import org.aspectj.lang.annotation.Around;
  10 import org.aspectj.lang.annotation.Aspect;
  11 import org.aspectj.lang.annotation.Pointcut;
  12
  13 @Aspect
  14 public class ExecutionAspect {
  15         private final static Log log = LogFactory.getLog(ExecutionAspect.class);
  16
  17         private ExecutionStack executionStack;
  18         private ExecutionContext executionContext;
  19
  20         @Around("flowExecution()")
  21         public void aroundFlow(ProceedingJoinPoint pjp) throws Throwable {
  22                 // IMPORTANT: Make sure that the execution context is called before the execution stack
  23                 executionContext.getUuid();
  24
  25                 ExecutionFlow executionFlow = (ExecutionFlow) pjp.getTarget();
  26                 executionStack.enterFlow(executionFlow);
  27                 executionContext.setVariable(ExecutionContext.VAR_FLOW_ID,
  28                                 executionStack.getCurrentStackLevelUuid());
  29                 executionContext.setVariable(ExecutionContext.VAR_FLOW_NAME,
  30                                 executionFlow.getName());
  31
  32                 if (log.isDebugEnabled())
  33                         logStackEvent("=> ", executionFlow);
  34                 // Actually execute the flow
  35                 pjp.proceed();
  36                 if (log.isDebugEnabled())
  37                         logStackEvent("<= ", executionFlow);
  38
  39                 executionStack.leaveFlow(executionFlow);
  40         }
  41
  42         @Around("getVariable()")
  43         public Object aroundGetVariable(ProceedingJoinPoint pjp) throws Throwable {
  44                 Object obj = pjp.proceed();
  45                 // if the variable was not found, look in the stack starting at the
  46                 // upper flows
  47                 if (obj == null) {
  48                         String key = pjp.getArgs()[0].toString();
  49                         obj = executionStack.findLocalVariable(key);
  50                 }
  51                 return obj;
  52         }
  53
  54         @Pointcut("execution(void org.argeo.slc.execution.ExecutionFlow.run())")
  55         public void flowExecution() {
  56         }
  57
  58         @Pointcut("execution(* org.argeo.slc.execution.ExecutionContext.getVariable(..))")
  59         public void getVariable() {
  60         }
  61
  62         public void setExecutionStack(ExecutionStack executionStack) {
  63                 this.executionStack = executionStack;
  64         }
  65
  66         public void setExecutionContext(ExecutionContext executionContext) {
  67                 this.executionContext = executionContext;
  68         }
  69
  70         protected void logStackEvent(String symbol, ExecutionFlow executionFlow) {
  71                 Integer stackSize = executionStack.getStackSize();
  72                 log.debug(depthSpaces(stackSize) + symbol + executionFlow + " #"
  73                                 + executionStack.getCurrentStackLevelUuid() + ", depth="
  74                                 + stackSize);
  75         }
  76
  77         private String depthSpaces(int depth) {
  78                 StringBuffer buf = new StringBuffer(depth * 2);
  79                 for (int i = 0; i < depth; i++)
  80                         buf.append("  ");
  81                 return buf.toString();
  82         }
  83
  84 }