How to use

computeProjectionRegions

method

in

org.eclipse.jface.text.source.projection.IProjectionPosition

/**
 * Computes the regions that must be collapsed when the given position is
 * the position of an expanded projection annotation.
 *
 * @param position the position
 * @return the ranges that must be collapsed, or <code>null</code> if
 *         there are none
 * @since 3.1
 */
IRegion[] computeCollapsedRegions(Position position) {
  try {
    IDocument document= getDocument();
    if (document == null)
      return null;
    if (position instanceof IProjectionPosition) {
      IProjectionPosition projPosition= (IProjectionPosition) position;
      return projPosition.computeProjectionRegions(document);
    }
    int line= document.getLineOfOffset(position.getOffset());
    int offset= document.getLineOffset(line + 1);
    int length= position.getLength() - (offset - position.getOffset());
    if (length > 0)
      return new IRegion[] {new Region(offset, length)};
    return null;
  } catch (BadLocationException x) {
    return null;
  }
}

/**
 * Computes the regions that must be collapsed when the given position is
 * the position of an expanded projection annotation.
 *
 * @param position the position
 * @return the ranges that must be collapsed, or <code>null</code> if
 *         there are none
 * @since 3.1
 */
IRegion[] computeCollapsedRegions(Position position) {
  try {
    IDocument document= getDocument();
    if (document == null)
      return null;
    if (position instanceof IProjectionPosition) {
      IProjectionPosition projPosition= (IProjectionPosition) position;
      return projPosition.computeProjectionRegions(document);
    }
    int line= document.getLineOfOffset(position.getOffset());
    int offset= document.getLineOffset(line + 1);
    int length= position.getLength() - (offset - position.getOffset());
    if (length > 0)
      return new IRegion[] {new Region(offset, length)};
    return null;
  } catch (BadLocationException x) {
    return null;
  }
}