Class GapContent

Constructor Detail

• GapContent

  public GapContent()

  Creates a new GapContent object. Initial size defaults to 10.

• GapContent

  public GapContent(int initialLength)

  Creates a new GapContent object, with the initial size specified. The initial size will not be allowed to go below 2, to give room for the implied break and the gap.

  Parameters:

  initialLength - the initial size

Method Detail

• allocateArray

  protected Object allocateArray(int len)

  Allocate an array to store items of the type appropriate (which is determined by the subclass).

• getArrayLength

  protected int getArrayLength()

  Get the length of the allocated array.

• length

  public int length()

  Returns the length of the content.

  Specified by:

  length in interface AbstractDocument.Content

  Returns:

  the length >= 1

  See Also:

  AbstractDocument.Content.length()

• insertString

  public UndoableEdit insertString(int where,
                          String str)
                            throws BadLocationException

  Inserts a string into the content.

  Specified by:

  insertString in interface AbstractDocument.Content

  Parameters:

  where - the starting position >= 0, < length()

  str - the non-null string to insert

  Returns:

  an UndoableEdit object for undoing

  Throws:

  BadLocationException - if the specified position is invalid

  See Also:

  AbstractDocument.Content.insertString(int, java.lang.String)

• remove

  public UndoableEdit remove(int where,
                    int nitems)
                      throws BadLocationException

  Removes part of the content.

  Specified by:

  remove in interface AbstractDocument.Content

  Parameters:

  where - the starting position >= 0, where + nitems < length()

  nitems - the number of characters to remove >= 0

  Returns:

  an UndoableEdit object for undoing

  Throws:

  BadLocationException - if the specified position is invalid

  See Also:

  AbstractDocument.Content.remove(int, int)

• getString

  public String getString(int where,
                 int len)
                   throws BadLocationException

  Retrieves a portion of the content.

  Specified by:

  getString in interface AbstractDocument.Content

  Parameters:

  where - the starting position >= 0

  len - the length to retrieve >= 0

  Returns:

  a string representing the content

  Throws:

  BadLocationException - if the specified position is invalid

  See Also:

  AbstractDocument.Content.getString(int, int)

• getChars

  public void getChars(int where,
              int len,
              Segment chars)
                throws BadLocationException

  Retrieves a portion of the content. If the desired content spans the gap, we copy the content. If the desired content does not span the gap, the actual store is returned to avoid the copy since it is contiguous.

  Specified by:

  getChars in interface AbstractDocument.Content

  Parameters:

  where - the starting position >= 0, where + len <= length()

  len - the number of characters to retrieve >= 0

  chars - the Segment object to return the characters in

  Throws:

  BadLocationException - if the specified position is invalid

  See Also:

  AbstractDocument.Content.getChars(int, int, javax.swing.text.Segment)

• createPosition

  public Position createPosition(int offset)
                          throws BadLocationException

  Creates a position within the content that will track change as the content is mutated.

  Specified by:

  createPosition in interface AbstractDocument.Content

  Parameters:

  offset - the offset to track >= 0

  Returns:

  the position

  Throws:

  BadLocationException - if the specified position is invalid

• shiftEnd

  protected void shiftEnd(int newSize)

  Make the gap bigger, moving any necessary data and updating the appropriate marks

• shiftGap

  protected void shiftGap(int newGapStart)

  Move the start of the gap to a new location, without changing the size of the gap. This moves the data in the array and updates the marks accordingly.

• resetMarksAtZero

  protected void resetMarksAtZero()

  Resets all the marks that have an offset of 0 to have an index of zero as well.

• shiftGapStartDown

  protected void shiftGapStartDown(int newGapStart)

  Adjust the gap end downward. This doesn't move any data, but it does update any marks affected by the boundary change. All marks from the old gap start down to the new gap start are squeezed to the end of the gap (their location has been removed).

• shiftGapEndUp

  protected void shiftGapEndUp(int newGapEnd)

  Adjust the gap end upward. This doesn't move any data, but it does update any marks affected by the boundary change. All marks from the old gap end up to the new gap end are squeezed to the end of the gap (their location has been removed).

• getPositionsInRange

  protected Vector getPositionsInRange(Vector v,
                           int offset,
                           int length)

  Returns a Vector containing instances of UndoPosRef for the Positions in the range offset to offset + length. If v is not null the matching Positions are placed in there. The vector with the resulting Positions are returned.

  Parameters:

  v - the Vector to use, with a new one created on null

  offset - the starting offset >= 0

  length - the length >= 0

  Returns:

  the set of instances

• updateUndoPositions

  protected void updateUndoPositions(Vector positions,
                         int offset,
                         int length)

  Resets the location for all the UndoPosRef instances in positions.

  This is meant for internal usage, and is generally not of interest to subclasses.

  Parameters:

  positions - the UndoPosRef instances to reset

• getArray

  protected final Object getArray()

  Access to the array. The actual type of the array is known only by the subclass.

• getGapStart

  protected final int getGapStart()

  Access to the start of the gap.

• getGapEnd

  protected final int getGapEnd()

  Access to the end of the gap.

• replace

  protected void replace(int position,
             int rmSize,
             Object addItems,
             int addSize)

  Replace the given logical position in the storage with the given new items. This will move the gap to the area being changed if the gap is not currently located at the change location.

  Parameters:

  position - the location to make the replacement. This is not the location in the underlying storage array, but the location in the contiguous space being modeled.

  rmSize - the number of items to remove

  addItems - the new items to place in storage.