Implements javax.swing.tree.TreeCellRenderer.getTreeCellRendererComponent.

Doc from javax.swing.tree.TreeCellRenderer.getTreeCellRendererComponent.

Sets the value of the current tree cell to value. If selected is true, the cell will be drawn as if selected. If expanded is true the node is currently expanded and if leaf is true the node represents a leaf and if hasFocus is true the node currently has focus. tree is the JTree the receiver is being configured for. Returns the Component that the renderer uses to draw the value.

The TreeCellRenderer is also responsible for rendering the the cell representing the tree's current DnD drop location if it has one. If this renderer cares about rendering the DnD drop location, it should query the tree directly to see if the given row represents the drop location:

    JTree.DropLocation dropLocation = tree.getDropLocation();
    if (dropLocation != null
            && dropLocation.getChildIndex() == -1
            && tree.getRowForPath(dropLocation.getPath()) == row) {

        // this row represents the current drop location
        // so render it specially, perhaps with a different color
    }

Overrides javax.swing.JComponent.paintComponent.

Doc from javax.swing.JComponent.paintComponent.

Calls the UI delegate's paint method, if the UI delegate is non-null. We pass the delegate a copy of the Graphics object to protect the rest of the paint code from irrevocable changes (for example, Graphics.translate).

If you override this in a subclass you should not make permanent changes to the passed in Graphics. For example, you should not alter the clip Rectangle or modify the transform. If you need to do these operations you may find it easier to create a new Graphics from the passed in Graphics and manipulate it. Further, if you do not invoke super's implementation you must honor the opaque property, that is if this component is opaque, you must completely fill in the background in an opaque color. If you do not honor the opaque property you will likely see visual artifacts.

The passed in Graphics object might have a transform other than the identify transform installed on it. In this case, you might get unexpected results if you cumulatively apply another transform.