The popularity of Java is now a commercial fact of life. Research into how best to provide persistence (convenient support for long-term data) for programming languages has been led by groups in Scotland for the last two decades. Java's popularity provides the long awaited opportunity to bring products from this research into widespread use.
There are many interfaces between Java and long-term storage (files, relational databases, or OO-databases). They all have a role to play, particularly for interacting with legacy systems. However they all introduce complexities and impose structures that seriously distract application programmers and distort application logic.
The PJava project (a joint effort between Sun Labs, California, and Glasgow University) has developed the Java implementation, PJama, which is available for non-commercial use and evaluation. This embodies the principles for persistent languages developed in Scotland and thereby supports application construction using long-lived data in a way that facilitates re-use and leaves the programmers free to focus on application logic.
The design, programming interface and implementation architecture will be described. This will be followed by a demonstration of applications written in the language, illustrating the gain from its simplicity and showing the automatic persistence mechanisms in operation.