Java Stored Procedures Developer's Guide
Release 2 (8.1.6)
Part Number A81358-01
Before calling Java methods from SQL, you must publish them in the Oracle data dictionary. When you load a Java class into the database, its methods are not published automatically because Oracle does not know which methods are safe entrypoints for calls from SQL. To publish the methods, you must write call specifications (call specs), which map Java method names, parameter types, and return types to their SQL counterparts.