ScrollPaneWheelScroller.java 文件源码

public static int getIncrementFromAdjustable(Adjustable adj,
                                             MouseWheelEvent e) {
    if (log.isLoggable(PlatformLogger.Level.FINE)) {
        if (adj == null) {
            log.fine("Assertion (adj != null) failed");
        }
    }

    int increment = 0;

    if (e.getScrollType() == MouseWheelEvent.WHEEL_UNIT_SCROLL) {
        increment = e.getUnitsToScroll() * adj.getUnitIncrement();
    }
    else if (e.getScrollType() == MouseWheelEvent.WHEEL_BLOCK_SCROLL) {
        increment = adj.getBlockIncrement() * e.getWheelRotation();
    }
    return increment;
}