Passing complex java class by reference to JNI

Hello all ,
I need to pass a java class (with primitive class members) to JNI and let the C++ update class member values so java would automatically get the new values.
I also would like to return such a class from JNI to java..
Is it possible ?
I would be happy to get some examples ...
thanks

1. Passing an object is trivial. Define the java class, instantiate an object, and pass it as a parameter of your native method.
2. Calling methods of that object is standard JNI. You must
o Look up the class.
o Look up the method.
o Call the method.
3. Returning a java object from C is trivial. Just make it a parameter of your return statement. However you might want to think about whether you really need to do that; if it was an object passed with the native method call, then the object already exists within java. Otherwise, you will have to consider using JNI to instantiate java objects.
Start with the tutorials. If this project gets extensive, then I recommend buying a book on JNI.

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Hello,
Can we pass int value by reference?
At least by passing it's wrapper class.
class Test
     public static void main(String args[])
          Integer myInt = 0;
          Test.testInteger(myInt, 5);
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     static void testInteger(Integer val, int value)
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}The code above surprisingly instead of outputting '5', it outputs '0'.
Isn't it passing object is always by reference?
Why it's not the case for primitive Wrapper class?
Is there any way to do this (pass by reference)?
Regards,
Heru

No! References to objects are passed by copy soif
you chage the copy you do not change theoriginal.
All values in Java are passed by copy. But when it's an object of a class, it works "by
reference".Java references are like pointer in C++ and not
references in C++. They are just called references
even though they are pointers.Yeah, but Integer is "just the same" with other class created by me (subclass of Object), why is the behavior different?

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http://www.oracle.com/technetwork/developer-tools/forms/webservices-forms-11g-094111.html
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Edit: too slow somehow -.- heading for a cup of black coffee
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a NUMBER,
b NUMBER,
s NUMBER,
d NUMBER,
p NUMBER,
q NUMBER
AS
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name 'MathEx.main(oracle.sql.NUMBER,oracle.sql.NUMBER,
oracle.sql.NUMBER,oracle.sql.NUMBER,oracle.sql.NUMBER,oracle.sql.NUMBER,)';
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oracle.sql.NUMBER
java.lang.Number
java.lang.Double
java.Math.BigDecimal
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Java Stored Procedures Developers Guide (part of the docs and here on OTN) would probably help.
I suspect you need:
create or replace procedure Call_MathEx
a IN NUMBER,
b IN NUMBER,
s OUT NUMBER,
d OUT NUMBER,
p OUT NUMBER,
q OUT NUMBER
AS
language JAVA
name 'MathEx.main(oracle.sql.NUMBER,oracle.sql.NUMBER,
oracle.sql.NUMBER,oracle.sql.NUMBER,oracle.sql.NUMBER,oracle.sql.NUMBER,)';
Not sure, I always let JDeveloper handle it for me :)

Passing complex java class by reference to JNI

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