Adding busniess rule validation at runtime

Recently I came across the following link:

http://mahmoudoracle.blogspot.com/2012/07/add-validation-at-runtime-in-adf.html#.Up8iF-KGPu3

and tried to test it myself, there were some issue but it worked out eventually.

 I modified the requirements to achieve the following:

a. add an expression validator at runtime with custom message.

b. remove the added validator at runtime.

here are the detailed steps to do it:

1.  create a new ADF application.
2. in the model project create new business components from tables - will use the employees table from the HR schema.
3. open the entity and generate :EntityObjectImpl and EntityDefImpl
4. in the entityDefImpl add the following code:

     String addExpressionValidator(String attributeName, String groovyExpression,
                                String errorMessage) {
        AttributeDef attributeDef = findAttributeDef(attributeName);

        JboExpressionValidator jboExpressionValidator =
            new JboExpressionValidator(false, groovyExpression);
        jboExpressionValidator.setErrorMsgId("dynamic_Message");
        Map map = new HashMap();
        map.put("0", errorMessage);
        jboExpressionValidator.setErrorMsgExpressions(map);
        ((AttributeDefImpl)attributeDef).addValidator(jboExpressionValidator);
        jboExpressionValidator.setName(jboExpressionValidator.getName()+System.currentTimeMillis());
        return jboExpressionValidator.getName();

    }

    void removeExpressionValidator(String attributeName,
                                   String validatorName) {
        AttributeDefImpl attributeDef =
            (AttributeDefImpl)findAttributeDef(attributeName);
        List validators = attributeDef.getValidators();
        JboAbstractValidator targetValidator = null;
        for (Object _validator : validators) {
            targetValidator = (JboAbstractValidator)_validator;
            if (targetValidator.getName().equalsIgnoreCase(validatorName)) {
                break;
            }
        }
        attributeDef.removeValidator(targetValidator);

    }

  5.in the bundle used for the messages of the model add the following:

dynamic_Message={0}

6. expose the above method as a viewobject method.

 7, design the apge as you see fit

now at runtime  

as you can see I added the folloing:

attribute name:Salary

Expression:newValue<=oldValue*1.5

message: "new salary value("+newValue+") should be less than or equal to old salary value("+oldValue+"*1.5)"

please note the message, the adf processes this message as a groovy expression.