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 palettes are included in the Design view. If you prefer to have more space to work in, you can choose to 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 also choose to show or hide the palette in the by using the small arrows next to the palette.