DropTarget.java 文件源码

/**
 * Creates a new DropTarget given the {@code Component}
 * to associate itself with, an {@code int} representing
 * the default acceptable action(s) to
 * support, a {@code DropTargetListener}
 * to handle event processing, a {@code boolean} indicating
 * if the {@code DropTarget} is currently accepting drops, and
 * a {@code FlavorMap} to use (or null for the default {@code FlavorMap}).
 * <P>
 * The Component will receive drops only if it is enabled.
 * @param c         The {@code Component} with which this {@code DropTarget} is associated
 * @param ops       The default acceptable actions for this {@code DropTarget}
 * @param dtl       The {@code DropTargetListener} for this {@code DropTarget}
 * @param act       Is the {@code DropTarget} accepting drops.
 * @param fm        The {@code FlavorMap} to use, or null for the default {@code FlavorMap}
 * @exception HeadlessException if GraphicsEnvironment.isHeadless()
 *            returns true
 * @see java.awt.GraphicsEnvironment#isHeadless
 */
public DropTarget(Component c, int ops, DropTargetListener dtl,
                  boolean act, FlavorMap fm)
    throws HeadlessException
{
    if (GraphicsEnvironment.isHeadless()) {
        throw new HeadlessException();
    }

    component = c;

    setDefaultActions(ops);

    if (dtl != null) try {
        addDropTargetListener(dtl);
    } catch (TooManyListenersException tmle) {
        // do nothing!
    }

    if (c != null) {
        c.setDropTarget(this);
        setActive(act);
    }

    if (fm != null) {
        flavorMap = fm;
    } else {
        flavorMap = SystemFlavorMap.getDefaultFlavorMap();
    }
}