SelectionMargin OpenTool


The SelectionMargin OpenTool is an add-on for the Borland JBuilder IDE. It adds a selection margin to the left of each editor pane which has special selection behavior that is mostly the same as Microsoft Word.

It allows you to easily select whole lines and therefore makes it easier to copy, cut or delete whole lines. The selection margin is also used to display line numbers.


When the mouse pointer is moved into the selection margin, it changes to a select arrow that points up and to the right (a mirror image of the standard select arrow).Do any of the following:

  • Click in the margin to select the entire line to the right of the mouse pointer.
  • Click in the margin and move the mouse pointer to select multiple consecutive lines.
  • While holding down SHIFT, click in the margin and move the mouse pointer to extend a selection.
  • While holding down CTRL, click anywhere in the margin to select the entire file. (This is equivalent to choosing the Select All command from the Edit menu.)


You can enable/disable the line number display in the Editor Options dialog.

A faster way to toggle the line number display is the popup menu of the selection margin. Right-click into the selection margin to get it.


  1. Quit JBuilder.
  2. Copy the SelectionMarginOpenTool.jar file into the <JBUILDER_HOME>\lib\ext directory.
  3. Restart JBuilder.


  1. Quit JBuilder.
  2. Delete the SelectionMarginOpenTool.jar file from the <JBUILDER_HOME>\lib\ext directory.
  3. Restart JBuilder.


This OpenTool has been tested with JBuilder 4, 5, 6 and 7.

Borland has integrated this OpenTool into JBuilder 8 (with my permission).


Version 2.2 (2002-04-08)

  • Support for the TextDragDrop OpenTool added.

Version 2.01 (2002-01-28)

  • Linux createCustomCursor() bug fixed.

Version 2.0 (2002-01-24)

  • Displays line numbers in the selection margin.
  • The selection margin is now installed into almost all editor panes (except the Diff View).
  • Split view support.
  • Added support for the “About OpenTools” OpenTool.

Version 1.1 (2001-11-24)

  • Select the entire file while holding down CTRL.

Version 1.0 (2001-11-18)

  • Initial release