Question

This question is about a proper architecture using JSP as a controller for ExtJS.

I am fairly new to server side development but I am pretty familiar with ExtJS 4 and getting better with Java and SQL daily.

I am trying to create a JSP controller to write the data from stores in ExtJS. I have MSSQL database and Tomcat running on the server.

I successfully created a JSP (sqlData.jsp) that reads from the database and returns JSON data. I pass a query name to this JSP, it then looks up what the query is from a “query” table (columns: [query_id],[query_name],[query]). It then runs the query and returns the data in a JSON format – this is working fine to get data into ExtJS from a database.

To use this backend set-up I usually configure the store like this:

var store = Ext.create('Ext.data.Store', {
    model: 'aModel',
    proxy: {
        type: 'ajax',
        url: 'sqlData.jsp?queryName=aQueryName',
        reader: 'json'
    },
    autoLoad: true
});

Somehow, I need this sqlData.jsp to also handle a store.save() call from the ExtJS framework. Which means the JSP needs to receive a POST request and then do an update based on a pile of JSON data (ExtJS sends read request as GET and write methods like store.save() are POST).

My plan was to add something in the Java to recognize whether it is a POST or GET request. Then, if it is a POST request, I would send it to a different Java method in the JSP to parse the JSON and write it to the database.

Of course I would have to change my “query” table to have another column for update/insert statements linked to the same queryName (i.e.: [query_id],[query_name],[select_query],[update_query]).

Does this backend implementation make any sense?

Anyone else use JSP and ExtJS to achieve this smoother?

I noticed that there is an api config option I can set in my proxy to specify different URLs for the different operations (READ, WRITE, DELETE, etc). Should I make a separate JSP and direct all write requests using this config instead?

Would it be wiser to add a writer: 'json' config on the proxy so that it parses before POSTING? I figured I would have to parse it in the JSP either way so I didn’t think I should.

Any pointers will be much appreciated.

Answer 1

since your backend is Java, I would really recommend using Spring 3.0 MVC to code your backend.

JSP is not a good option for the stuff you are doing because:

1. the functions you write in there are not unit testable.
2. the functions you write in there are not reusable.
3. the code you write in JSP are functional in nature, not object oriented, you can’t inject the services you need into your JSP.

Spring 3.0 MVC has really good synergy with ExtJS 4, namely the RESTful URL’s and content negotiation.

This example shows how to integrate the two things together. http://java.dzone.com/articles/extjs-4-file-upload-spring-mvc