I suspect you're probably right, though I haven't dug into the details because I found a workaround. I finally got it to work when, instead of creating new objects & storing their references in the array, I just called the getters of the existing references in the array.

This is obviously a place where the documentation needs major expansion & clarification.

_______________________________

Hardware /nm./: the part of the computer you can kick.

Michael Brewer-Davis <mich...@tech4learning.com> 06/20/2008 12:58 PM Please respond to use...@jna.dev.java.net

To use...@jna.dev.java.net cc

Subject Re: [jna-users] Wrong Structure Values Passed

RWAD...@UP.COM wrote:

Not an expert, but I think you misunderstand this toArray call. The javadoc:

public Structure[] toArray(Structure[] array) Returns a view of this structure's memory as an array of structures. Note that this Structure must have a public, no-arg constructor. If the structure is currently using a Memory backing, the memory will be resized to fit the entire array.

I parse that as (a) the first element of the returned array will be "this" (b) subsequent elements of the returned array will be from "this"'s memory

This fits your data: (a) first point is Java allocated 0, 0 (b) second point is newly (C) allocated gibberish

The purpose would be to treat Structure* values passed from C as Structure[] values when appropriate. The array param just reuses that array, reduces that allocation.

One possible solution? Point p = new Point(1, 2); Point[] points = p.toArray(2); p[1].setPoint(3, 4); // or some other assignment

Maybe something more elegant.

michael