Spring | SPEL multiple property accessors - spring

Question

I'm trying to use SPeL with multiple property accessors.
StandardEvaluationContext simpleContext = new StandardEvaluationContext(myPojo);
simpleContext.setVariable("ctx", ruleExecutionContext);
simpleContext.setPropertyAccessors(Arrays.asList(new MapAccessor(), new ReflectivePropertyAccessor()));
ExpressionParser parser = new SpelExpressionParser();
return (Boolean) parser.parseExpression(spelExpression).getValue(simpleContext, RulebaseConfiguration.LIB_MAP);
RulebaseConfiguration.LIB_MAP contains {"instanceName": instance}
I want to pass expressions that could operate on a POJO as well as call methods on the instance. But it only takes map into the effect.
I get this error:
SEVERE: Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'payload' cannot be found on object of type 'java.util.HashMap' - maybe not public?] with root cause
org.springframework.expression.spel.SpelEvaluationException: EL1008E: Property or field 'payload' cannot be found on object of type 'java.util.HashMap' - maybe not public?
at org.springframework.expression.spel.ast.PropertyOrFieldReference.readProperty(PropertyOrFieldReference.java:226)

Answer 1

Creating a context and parsing the expression for each request is wasteful, unless it's different for each request; in which case, consider caching expressions/contexts.
As I said, since you are passing a rootObject to getValue(), your myPojo is "hidden" - the evaluation is always performed on LIB_MAP.
You need to call getValue() without a root object to use the context's root object. You can add LIB_MAP as a variable (e.g. with name nationalityLookup) and use
payload['channel'] == #nationalityLookup.resolveChannel('CBR1000')