org.eclipse.jface.text
Class DefaultPositionUpdater
java.lang.Object
org.eclipse.jface.text.DefaultPositionUpdater
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All Implemented Interfaces:
-
IPositionUpdater
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Direct Known Subclasses:
-
MultiPassContentFormatter.NonDeletingPositionUpdater
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public class DefaultPositionUpdater
- extends
Object
- implements
IPositionUpdater
Default implementation of
IPositionUpdater.
A default position updater must be configured with the position category whose positions it will
update. Other position categories are not affected by this updater.
This implementation follows the specification below:
- Inserting or deleting text before the position shifts the position accordingly.
- Inserting text at the position offset shifts the position accordingly.
- Inserting or deleting text strictly contained by the position shrinks or stretches the
position.
- Inserting or deleting text after a position does not affect the position.
- Deleting text which strictly contains the position deletes the position. Note that the
position is not deleted if its only shrunken to length zero. To delete a position, the
modification must delete from strictly before to strictly after the position.
- Replacing text overlapping with the position is considered as a sequence of first deleting
the replaced text and afterwards inserting the new text. Thus, a position might first be shifted
and shrunken and then be stretched.
This class can be used as is or be adapted by subclasses. Fields are protected to allow
subclasses direct access. Because of the frequency with which position updaters are used this is
a performance decision.
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Method Summary
|
protected void
|
adaptToInsert
()
Adapts the currently investigated position to an insertion. |
protected void
|
adaptToRemove
()
Adapts the currently investigated position to a deletion. |
protected void
|
adaptToReplace
()
Adapts the currently investigated position to the replace operation. |
protected
String
|
getCategory
()
Returns the category this updater is responsible for. |
protected boolean
|
isAffectingReplace
()
Returns whether the current event describes a well formed replace
by which the current position is directly affected. |
protected boolean
|
notDeleted
()
Determines whether the currently investigated position has been deleted by
the replace operation specified in the current event. |
void
|
update
(
DocumentEvent event)
Adapts positions to the change specified by the document event. |
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Methods inherited from class java.lang.
Object
|
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
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fPosition
protected
Position fPosition
- Caches the currently investigated position
fOriginalPosition
protected
Position fOriginalPosition
- Remembers the original state of the investigated position
-
Since:
- 2.1
fOffset
protected int fOffset
- Caches the offset of the replaced text
fLength
protected int fLength
- Caches the length of the replaced text
fReplaceLength
protected int fReplaceLength
- Caches the length of the newly inserted text
fDocument
protected
IDocument fDocument
- Catches the document
DefaultPositionUpdater
public DefaultPositionUpdater(
String category)
- Creates a new default position updater for the given category.
-
Parameters:
-
category - the category the updater is responsible for
getCategory
protected
String getCategory()
- Returns the category this updater is responsible for.
-
-
-
Returns:
- the category this updater is responsible for
isAffectingReplace
protected boolean isAffectingReplace()
- Returns whether the current event describes a well formed replace
by which the current position is directly affected.
-
-
-
Returns:
-
true the current position is directly affected -
Since:
- 3.0
adaptToInsert
protected void adaptToInsert()
- Adapts the currently investigated position to an insertion.
-
-
adaptToRemove
protected void adaptToRemove()
- Adapts the currently investigated position to a deletion.
-
-
adaptToReplace
protected void adaptToReplace()
- Adapts the currently investigated position to the replace operation.
First it checks whether the change replaces the whole range of the position.
If not, it performs first the deletion of the previous text and afterwards
the insertion of the new text.
-
-
notDeleted
protected boolean notDeleted()
- Determines whether the currently investigated position has been deleted by
the replace operation specified in the current event. If so, it deletes
the position and removes it from the document's position category.
-
-
-
Returns:
-
true if position has not been deleted
update
public void update(
DocumentEvent event)
-
Description copied from interface:
IPositionUpdater
- Adapts positions to the change specified by the document event.
It is ensured that the document's partitioning has been adapted to
this document change and that all the position updaters which have
a smaller index in the document's position updater list have been called.
-
-
Specified by:
-
update
in interface
IPositionUpdater
-
-
Parameters:
-
event - the document event describing the document change
Guidelines for using Eclipse APIs.
Copyright (c) Eclipse contributors and others 2000, 2008. All rights reserved.
