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Oracle9i SQL Reference
Release 2 (9.2)

Part Number A96540-02
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CREATE JAVA

Purpose

Use the CREATE JAVA statement to create a schema object containing a Java source, class, or resource.

See Also:

Prerequisites

To create or replace a schema object containing a Java source, class, or resource in your own schema, you must have CREATE PROCEDURE system privilege. To create such a schema object in another user's schema, you must have CREATE ANY PROCEDURE system privilege. To replace such a schema object in another user's schema, you must also have ALTER ANY PROCEDURE system privilege.

Syntax

create_java::=

Text description of statements_511.gif follows
Text description of create_java


invoker_rights_clause::=

Text description of statements_542.gif follows
Text description of invoker_rights_clause


Semantics

OR REPLACE

Specify OR REPLACE to re-create the schema object containing the Java class, source, or resource if it already exists. Use this clause to change the definition of an existing object without dropping, re-creating, and regranting object privileges previously granted.

If you redefine a Java schema object and specify RESOLVE or COMPILE, Oracle recompiles or resolves the object. Whether or not the resolution or compilation is successful, Oracle invalidates classes that reference the Java schema object.

Users who had previously been granted privileges on a redefined function can still access the function without being regranted the privileges.

See Also:

ALTER JAVA for additional information

RESOLVE | COMPILE

RESOLVE and COMPILE are synonymous keywords. They specify that Oracle should attempt to resolve the Java schema object that is created if this statement succeeds.

Restriction on RESOLVE and COMPILE

You cannot specify this clause for a Java resource.

NOFORCE

Specify NOFORCE to roll back the results of this CREATE command if you have specified either RESOLVE or COMPILE, and the resolution or compilation fails. If you do not specify this option, Oracle takes no action if the resolution or compilation fails (that is, the created schema object remains).

JAVA SOURCE Clause

Specify JAVA SOURCE to load a Java source file.

JAVA CLASS Clause

Specify JAVA CLASS to load a Java class file.

JAVA RESOURCE Clause

Specify JAVA RESOURCE to load a Java resource file.

NAMED Clause

The NAMED clause is required for a Java source or resource. The primary_name must be enclosed in double quotation marks.

Use double quotation marks to preserve a lower- or mixed-case primary_name.

If you do not specify schema, Oracle creates the object in your own schema.

Restrictions on NAMED

SCHEMA Clause

The SCHEMA clause applies only to a Java class. This optional clause specifies the schema in which the object containing the Java file will reside. If you do not specify this clause, Oracle creates the object in your own schema.

invoker_rights_clause

Use the invoker_rights_clause to indicate whether the methods of the class execute with the privileges and in the schema of the user who owns the class or with the privileges and in the schema of CURRENT_USER.

This clause also determines how Oracle resolves external names in queries, DML operations, and dynamic SQL statements in the member functions and procedures of the type.

AUTHID CURRENT_USER

CURRENT_USER indicates that the methods of the class execute with the privileges of CURRENT_USER. This clause is the default and creates an invoker-rights class.

This clause also specifies that external names in queries, DML operations, and dynamic SQL statements resolve in the schema of CURRENT_USER. External names in all other statements resolve in the schema in which the methods reside.

AUTHID DEFINER

DEFINER indicates that the methods of the class execute with the privileges of the owner of the schema in which the class resides, and that external names resolve in the schema where the class resides. This clause creates a definer-rights class.

See Also:

RESOLVER Clause

The RESOLVER clause lets you specify a mapping of the fully qualified Java name to a Java schema object, where

This mapping is stored with the definition of the schema objects created in this command for use in later resolutions (either implicit or in explicit ALTER ... RESOLVE statements).

USING Clause

The USING clause determines a sequence of character (CLOB or BFILE) or binary (BLOB or BFILE) data for the Java class or resource. Oracle uses the sequence of characters to define one file for a Java class or resource, or one source file and one or more derived classes for a Java source.

BFILE Clause

Specify the directory and filename of a previously created file on the operating system (directory_object_name) and server file (server_file_name) containing the sequence. BFILE is usually interpreted as a character sequence by CREATE JAVA SOURCE and as a binary sequence by CREATE JAVA CLASS or CREATE JAVA RESOURCE.

CLOB | BLOB | BFILE subquery

Specify a query that selects a single row and column of the type specified (CLOB, BLOB, or BFILE). The value of the column makes up the sequence of characters.


Note:

In earlier releases, the USING clause implicitly supplied the keyword SELECT. This is no longer the case. However, the subquery without the keyword SELECT is still supported for backward compatibility.


key_for_BLOB

The key_for_BLOB clause supplies the following implicit query:

SELECT LOB FROM CREATE$JAVA$LOB$TABLE 
   WHERE NAME = 'key_for_BLOB';

Restriction on the key_for_BLOB Clause

To use this case, the table CREATE$JAVA$LOB$TABLE must exist in the current schema and must have a column LOB of type BLOB and a column NAME of type VARCHAR2.

AS source_text

Specify a sequence of characters for a Java or SQLJ source.

Examples

Creating a Java Class Object: Example

The following statement creates a schema object containing a Java class using the name found in a Java binary file:

CREATE JAVA CLASS USING BFILE (bfile_dir, 'Agent.class');

This example assumes the directory object bfile_dir, which points to the operating system directory containing the Java class Agent.class, already exists. In this example, the name of the class determines the name of the Java class schema object.

Creating a Java Source Object: Example

The following statement creates a Java source schema object:

CREATE JAVA SOURCE NAMED "Hello" AS
   public class Hello {
      public static String hello() {
         return "Hello World";   } };
Creating a Java Resource Object: Example

The following statement creates a Java resource schema object named apptext from a bfile:

CREATE JAVA RESOURCE NAMED "appText" 
   USING BFILE (bfile_dir, 'textBundle.dat');