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C++ -> Java -- Multiple Return Values

843829Oct 31 2006 — edited Nov 2 2006

I am in need to multiple values from a method.
A status code (int) and a return value (double).

From what I have read -- it is customary to use an object array to handle this, since java does not support out parameters.

When I return the Object[] through JNI as a jobjectArray how do I obtain(cast) the values as int and double???

This is how I am getting the values from the array via JNI. However the cast to jint does not work as expected.

jsize numOfObjects = m_env->GetArrayLength(attrReturnArray);

if ( numOfObjects >= 2 )
{
   jint status = (jint)m_env->GetObjectArrayElement(attrReturnArray, 0);
   jint retValue = (jint)m_env->GetObjectArrayElement(attrReturnArray, 1);
}

Any sugestions?

thatJeffSmith-Oracle

I understand what you want, however I don't think we have an answer that will give you what you want.

PL/SQL blocks aren't SQL - you're not going to get a resultset back like what if you had run a query in SQL*Plus or SQL Developer.

HOWEVER, if you have your program return the resultset as a REFCURSOR - SQL Developer will 'catch' that output and place it in a 'grid.'

You're other option is to output the format to file or to the output buffer however which way you want - but that's code you're going to have to write yourself.

Here's an example of what REFCURSOR output looks like in SQL Developer

http://www.thatjeffsmith.com/archive/2011/12/sql-developer-tip-viewing-refcursor-output/

unknown-7404

Welcome to the forum!

Whenever you post provide your full sql developer version.
>
But output via PL/SQL is usually done via dbms_output.
>
No - it isn't.

The DBMS_OUTPUT package should NOT be used at all in production code. You should only enable and use it very sparingly and only then for debugging purposes when developing and testing your code.

A line like this:

    dbms_output.put_line(i || ' ' || i*i);

does nothing more than put text into a buffer in Oracle and uses expensive PGA memory to store it. There is a small default limit on the size of that buffer and you run the risk of an exception if you fill it up.

The client software (sql*plus, sql developer) has to actually access that buffer to get the text or it will NEVER get displayed. And it normally only gets displayed AFTER the completion of the code, not during the execution.

If you are using DBMS_OUTPUT as a general-purpose 'display' mechanism then you are misusing it and should find another alternative.
>
How to get the resulting table not shown in the "dbms output" window, but in the "query result" window?
>
There is no 'table' and there is no 'query result'. If you want a query result put the results into a table or use a REF CURSOR to return them.

thatJeffSmith-Oracle

No - it isn't.

Good catch. Although unfortunately too many folks do rely on this. And of course it's never in production. Sigh.

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Java HotSpot Virtual Machine

C++ -> Java -- Multiple Return Values

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