Solved

JNI: Returning a struct from C

Posted on 1997-05-09
2
814 Views
Last Modified: 2006-11-17
I'm using JDK1.1, MSVC++

Say I have a struct in my C program:

struct foo {
        int a;
        int b;
        int *c;
}

(c is an array of ints, length b)

Is there any way using the JNI to return this to Java?

If not, what's the alternative?  Call NewObject, and pass each arg separately to the constuctor?

(code fragment if possible..)

Thanks,

M.
0
Comment
Question by:champine
2 Comments
 

Accepted Solution

by:
aruns earned 100 total points
ID: 1220308
Hi,
Any structure is represented as a class in Java. So, if you have to pass your struct foo, it must be an object. For this you will have to have to have a foo class in Java like :

class foo      
{
      int      a ;
      int[]    c ;

      // Additional lines of code necessary
}

In your native code when your are passing it back, your will have to do two things  :

      1. Create a integer array NewIntArray() JNI call and fill in all the values of c into the array.
      2. Create a new Java foo object with variable a and the new integer array created and pass it back to Java.

In case of any clarifications, please comment.
0
 

Author Comment

by:champine
ID: 1220309
With a code fragment, or even pseudo-code, I'd give it an "A" rating;

0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
mockito example issue 8 72
jar file executable 12 52
servlet example issue 6 39
check java version using powershell 13 92
Introduction This article is the last of three articles that explain why and how the Experts Exchange QA Team does test automation for our web site. This article covers our test design approach and then goes through a simple test case example, how …
Java functions are among the best things for programmers to work with as Java sites can be very easy to read and prepare. Java especially simplifies many processes in the coding industry as it helps integrate many forms of technology and different d…
This tutorial covers a step-by-step guide to install VisualVM launcher in eclipse.
Viewers will learn how to properly install Eclipse with the necessary JDK, and will take a look at an introductory Java program. Download Eclipse installation zip file: Extract files from zip file: Download and install JDK 8: Open Eclipse and …

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question