A few weeks ago, I had a scenario come up where I wanted to be able to filter an Ext.data.Store based on a set of criteria, part of which depended upon a value in one of my model’s associations. While this is easy enough to do via filterBy(), it can become a bit unwieldy to use, especially if you want/need the criteria to be dynamically constructed.

As I was thinking about how to best deal with this, I remembered my experiences of using ColdBox’s CriteriaBuilder, which is based on Hibernate’s API of the same name. Using CriteriaBuilder, you can-among myriad other things-produce complex queries and, because it is all DSL-based, criteria can be added in as dynamic a way as you’d like.

This inspired me to experiment with building a CriteriaBuilder for Ext JS.

CriteriaBuilder

CriteriaBuilder allows you to build complex, dynamic queries that can query any data within an Ext.data.Store, including association data. Since I was bored, I created two approaches for interfacing with CriteriaBuilder.

In the first approach, you can use a SQL-like syntax to craft your query. For example:

var cb = new CriteriaBuilder.Builder({
    store: mystore
});
var sql = 'join user u where u.lastName like "McD%" order by orderNumber ASC';
// run More >