Query Builder uses object model information to present the list of all possible types to build queries against. It does this by searching for all types that implement the wt.fc.NetFactor interface. However, there may be classes that do not implement the wt.fc.Net.Factor interface, yet have subclasses that implement the Persistable interface and therefore can be used in queries. An example is wt.index.Indexable. To allow queries to be built using these types, these types can be listed as resources in a service properties file. The out-of-the-box entry in dbservice.properties handles the Indexable interface as follows:

To customize the list of Query Builder types, new entries can be added. For example, for the class myPackage.myClass, the entry would be as follows:

This is necessary only if the class does not implement the NetFactor interface, but does have subclasses that implement the Persistable interface.