Question

I am designing an application with Spring MVC3. I have to create a JSP page which has a data table and user and can add rows in the JSP data table. I was considering the following two options:

1. To use JavaScript function to add a row on an "Insert Row" button
2. To submit the form on "Insert Row" button, go to Controller and return a model attribute with an extra row.

In JavaScript approach, I am able to add rows but these rows are not binding at server side. How can I achieve this using Controller approach?

Please note that I cannot use jQuery or any other JavaScript library.

Answer 1

I have achieved this using the LazyList. You need to have a lazy list object in your model which will hold the list of objects of the another model class which will represent data in each row. Following is the syntax to declare LazyList in your model class.

private List<OperationParameters> operationParameterses = LazyList
            .decorate(new ArrayList<OperationParameters>(),
                    FactoryUtils.instantiateFactory(OperationParameters.class));

And the OperationParameters is the simple pojo class whose one object will represent your 1 row.

Once you have this lazy list in your modelAttribute class then on the jsp you need to create control for each property in your OperationParameters pojo with help of simple html input tag. You can not use spring form taglib to bind those controls to your pojo. You need to give the name of each input tag as per following.

<input type='text' id='operationParameterses0.inputOutputParamName' name='operationParameterses[0].inputOutputParamName'/>

where in the name and id attribute the ‘0’ represents the index of the list. Now when you submit the form you can get those inserted rows binded to the pojo in the LazyList object.

Hope this helps you.

Cheers.