Oracle PL/SQL Programming, 5th Edition

Using DBMS_JAVA

The Oracle built-in package DBMS_JAVA gives you access to and the ability to modify various characteristics of the Java Virtual Machine in the database.

The DBMS_JAVA package contains a large number of programs, many of which are intended for Oracle internal use only. Nevertheless, we can take advantage of a number of very useful programs; most can also be called within SQL statements. Table 27-4 summarizes some of the DBMS_JAVA programs. As noted earlier in the chapter, DBMS_JAVA also offers programs to manage security and permissions.

Table 27-4. Common DBMS_JAVA programs

Program	Description
LONGNAME function	Obtains the full (long) Java name for a given Oracle short name
GET_COMPILER_OPTION function	Looks up an option in the Java options table
SET_COMPILER_OPTION procedure	Sets a value in the Java options table and creates the table, if one does not exist
RESET_COMPILER_OPTION procedure	Resets a compiler option in the Java options table
SET_OUTPUT procedure	Redirects Java output to the DBMS_OUTPUT text buffer
EXPORT_SOURCE procedure	Exports a Java source schema object into an Oracle LOB
EXPORT_RESOURCE procedure	Exports a Java resource schema object into an Oracle LOB
EXPORT_CLASS procedure	Exports a Java class schema object into an Oracle LOB

These programs are explored in more detail in the following sections.

LONGNAME: Converting Java Long Names

Java class names can easily exceed the maximum SQL identifier length of 30 characters. In such cases, Oracle creates a unique “short name” ...