private <T> T compileAndExecuteWithStrongTyping(String expression, Map vars) {
    ParserContext context = new ParserContext();
    context.setStrongTyping(true);
    context.setStrictTypeEnforcement(true);
    Serializable compiled = MVEL.compileExpression(expression, context);
    return (T) MVEL.executeExpression(compiled, vars);
  }