Frequently Asked Questions

What is Emeraldjb?
Emeraldjb is a O/R code generator for Oracle and MySQL databases. I uses either a schema or an xml document to generate DAO pattern bases classes. Emeraldjb is never prescriptive, it is a very pragmatic, simple O/R code generator.

How is it unique?
Experience has shown that most use of data is in two forms

• A commingled cross table retrieval for display of key fields in pick lists and searches.
• A row level mapping of data to objects for manipulation and store, and possible streaming for some reason or other.

This view of data is at the heart of Emeraldjb's approach.

• Searcher nuggets creating custom cross table search objects containing just the data needed. This is efficient, fast, and targeted at your requirements.
• Entities are a mapping of the schema for insert, update, delete and any custom selections that you require.

The patterns supported by Emerald do add significant value, from optimistic locking, audit and dual primary key patterns through to the full auto archiving pattern.

We have used Emeraldjb on many projects, sometimes using the runtime classes as they are shipped, and sometimes rewriting them to fit the projects environment and framework.

Why use Emeraldjb?
Because it is simple, and does not tie your project to any open source, or custom framework. It uses core libraries and is focused on getting the job done through practical code, rather than through mindless decoupling and obfuscation frameworks.

How is it standard?
The code generated uses a simple DAO pattern as described by Sun. The factory shipped is an example implementation, you may want to replace this with a factory configured by XML, it is up to you.

The code generated is easily extended because of the support for the Generation Gap - an extensible class for all values objects where you can add your own wrappers or additional data marshalling functions. For common functions, all generated values objects extend the same base class per package.

The code uses the standard libraries; jdbc and logging. If you want to add transaction control and distribution you may do this by embedding the generated code into another framework.