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[platform-swt-dev] Early dispose()

Title: Early dispose()

This code works on Windows XP, but to ensure cross platform portability, shouldn't it throw an execption :

        Color color1 = new Color(e.display,100,0,50);
        Color color2 = new Color(e.display,100,255,50);
        Pattern pattern = new Pattern(e.display,0,0,200,200,color1,color2);
        color1.dispose();
        color2.dispose(); // is it too early ???
               
        gc.setBackgroundPattern(pattern);
        pattern.dispose(); // THE PATTERN IS STILL IN USE
        gc.fillRectangle(0, 0, e.width, e.height);

On Windows, .dispose calls DeleteObject, and according to MSND, the objects assigned to GC should not be deleted. Windows XP is robust enough to resists such misuse. I don't know if Windows 98 of GTK can handle it.

A safe behavior of SWT would be to record that the pattern is in use by the GC, and when you try to dispose the pattern, either you get an exception or you dipose the GC causing the .fillRectangle() to throw an exception.

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