[rules-users] [MVEL]Getting Null Context Object with MVEL Inteceptor

[kapokfly]

  public void testMyInterceptors() {

    // Avoid MVEL OOM issue: http://jira.codehaus.org/browse/MVEL-252
    // This also disables JIT compilre
    // At this time, MVEL does not support per instance configuration of the
JIT due to performance constraints.
    OptimizerFactory.setDefaultOptimizer(OptimizerFactory.SAFE_REFLECTIVE);

    Interceptor testLeftInterceptor = new Interceptor() {
      public int doBefore(ASTNode node,
                          VariableResolverFactory factory) {
        System.out.println("BEFORE left Node: " + node.getName());
        System.out.println("BEFORE left Node: node.getClass(): " +
node.getClass());
        //node.setAsLiteral();
        //node.setLiteralValue("Ivan");
        System.out.println("BEFORE left Node: " + node.getLiteralValue());
        node.setAccessor(new MetaDataAccessor());
        return 0;
      }

      public int doAfter(Object val,
                         ASTNode node,
                         VariableResolverFactory factory) {
        System.out.println("AFTER left Node: " + node.getName());
        System.out.println("AFTER left Node: node.getLiteralValue(): " +
node.getLiteralValue());
        return 0;
      }
    };

    Interceptor testRightInterceptor = new Interceptor() {

      public int doBefore(ASTNode node,
                          VariableResolverFactory factory) {
        System.out.println("BEFORE right Node: " + node.getName());
        System.out.println("BEFORE right Node: node.getClass(): " +
node.getClass());
        return 0;
      }

      public int doAfter(Object val,
                         ASTNode node,
                         VariableResolverFactory factory) {
        System.out.println("AFTER right Node: " + node.getName());
        return 0;
      }
    };

    Map<String, Interceptor> interceptors = new HashMap<String,
Interceptor>();
    interceptors.put("testLeft", testLeftInterceptor);
    interceptors.put("testRight", testRightInterceptor);

    String expression = "(@testLeft emailMessage.from == @testRight 'Mark'
|| @testLeft myBean.var == 1)";
    //compileExpression(expression, null, interceptors);
    Map<String, Object> contextObjects = new HashMap<String, Object>();
    EmailMessage emailMessage = new EmailMessage();
    emailMessage.setFrom("Mark");
    contextObjects.put("emailMessage", emailMessage);

    MyBean myBean = new MyBean();
    myBean.setVar(1);
    contextObjects.put("myBean", myBean);

    boolean evaluationResult =
executeExpression(compileExpression(expression, null, interceptors),
contextObjects, Boolean.class);
    System.out.println(evaluationResult);
  }


public class MetaDataAccessor implements Accessor{
  public Object getValue(Object ctx, Object elCtx, VariableResolverFactory
variableFactory) {
    return null;  //To change body of implemented methods use File |
Settings | File Templates.
  }

  public Object setValue(Object ctx, Object elCtx, VariableResolverFactory
variableFactory, Object value) {
    return null;  //To change body of implemented methods use File |
Settings | File Templates.
  }

  public Class getKnownEgressType() {
    return null;  //To change body of implemented methods use File |
Settings | File Templates.
  }
}


When the MetaDataAccessor's geValue was invoked, the ctx and elCtx were
Null, however I am expecting the correct expression and context object
presents? 

What is wrong with my codes? 

I would expect the value reduce process can be done by my accessor in some
cases but apparently it is not. 



-----
Ivan, your Panda, forever
--
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