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Java Databases

We treat Java databases separately from other databases because open source pure Java databases are not as mature or as powerful as the non-Java databases. However, the Java databases do offer some advantages for the Java programmer. The Java databases are platform independent and easily run the system being used for development. The databases also tend to be small, making it easy to directly incorporate or embed the database as part of the application. Their small size, however, does not mean they are limited in the size of the database that they can handle. Most of these databases can handle files that are large enough for many applications. Some Java databases offer a feature allowing the data within the database to be completely stored in random access memory (RAM). This is great for performance but may cause problems if the system goes down before the disk files are written. This feature would normally be used for small very high-speed read-only database applications.