You can control how and whether views and palettes are displayed in the visual editor.
By default, the visual editor for Java shows the Design and Source views on a split pane, and the component palette is collapsed against the right side of the Design view. If you prefer to have more screen space for your work, you can stack the Design and Source views on separate tabs, rather than tiling them. You can also move the divider to show more or less of the Source view. In addition, you can resize the palette by dragging its border, or you can show or hide it by clicking the small arrow at the top of the palette.