Java Code, Binaries, and Resources Storage

In the Sun Microsystems Java development environment, Java source code, binaries, and resources are stored as files in a file system.

• Source code files are known as .java files.

• Compiled Java binary files are known as .class files.

• Resources are any data files, such as .properties or .ser files held within the file system hierarchy, which are loaded or used at runtime.

In addition, when you execute Java, you specify a CLASSPATH, which is a set of a file system tree roots containing your files. Java also provides a way to group these files into a single archive form--a ZIP or JAR file.

Both of these concepts are different within the database. The following describes how JServer handles Java classes and locates dependent classes:

Java code, binaries, and resources

In the JServer environment, source, classes, and resources reside within the Oracle8i database. Because they reside in the database, they are known as Java schema objects, where a schema corresponds to a database user. There are three types of Java objects: source, class, and resource. There are no .java, .class, .sqlj, .properties, or .ser files on the server; instead these files map to source, class, and resource Java schema objects.

Locating Java classes

Instead of a CLASSPATH, you use a resolver to specify one or more schemas to search for source, class, and resource Java schema objects.

The terms call and session, used during our discussions, are not Java terms; but are server terms that apply to the Oracle8i JServer platform. The Aurora memory manager preserves Java program state throughout your session (that is, between calls). The JServer uses the Oracle database to hold Java source, classes, and resources within a schema--Java schema objects. You can use a resolver to specify how Java, when executed in the server, locates source code, classes, and resources.

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