ASA Programming Guide
  Using Java in the Database
    Special features of Java classes in the database

Returning values from Java via stored procedures

You can use stored procedures created using the EXTERNAL NAME LANGUAGE JAVA as wrappers around Java methods. This section describes how to write your Java method to exploit OUT or INOUT parameters in the stored procedure.

Java does not have explicit support for INOUT or OUT parameters. Instead, you can use an array of the parameter. For example, to use an integer OUT parameter, create an array of exactly one integer:

public class TestClass {
  public static boolean testOut( int[] param ){
    param[0] = 123;
    return true;
  }
}

The following procedure uses the testOut method:

CREATE PROCEDURE sp_testOut ( OUT p INTEGER )
EXTERNAL NAME 'TestClass/testOut ([I)Z'
LANGUAGE JAVA

The string ([I)Z is a Java method signature, indicating that the method has a single parameter, which is an array of integers, and returns a Boolean value. You must define the method so that the method parameter you wish to use as an OUT or INOUT parameter is an array of a Java data type that corresponds to the SQL data type of the OUT or INOUT parameter.

For more information about the syntax, including the method signature, see CREATE PROCEDURE statement.