Description: You store application classes and resources by storing one or more jar files in the database. Then your application can access classes loaded by Derby from the jar file and does not need to be coded in a particular way. The only difference is the way in which you invoke the application.

# Class loading overview

You store application classes and resources by storing one or more jar files in the database. Then your application can access classes loaded by Derby from the jar file and does not need to be coded in a particular way. The only difference is the way in which you invoke the application.

Here are the basic steps.

1. Create jar files for your application
   Include any Java classes in a jar file that are intended for Derby class loading, except the following classes:
2. Add the jar file or files to the database
   Use a set of procedures to install, replace, and remove jar files in a database. When you install a jar file in a database, you give it a Derby jar name, which is an SQL92Identifier.
3. Enable database class loading with a property
   Once you have added one or more jar files to a database, you must set the database jar "classpath" by including the jar file or files in the derby.database.classpath property to enable Derby to load classes from the jar files.
4. Code your applications
   In your applications, you load the classes either by indirectly referencing them in the code or by directly using java.lang.Class.forName.

Parent topic: Loading classes from a database
Related concepts
Dynamic changes to jar files or to the database jar classpath
Signed jar files