IPresentationReconciler.
- * This implementation assumes that the tasks performed by its
- * presentation damagers and repairers are lightweight and of low cost.
- * This presentation reconciler runs in the UI thread and always repairs
- * the complete damage caused by a document change rather than just the
- * portion overlapping with the viewer's viewport.
- * Usually, clients instantiate this class and configure it before using it.
- */
-public class CPresentationReconciler implements IPresentationReconciler {
-
- protected final static String TRACKED_PARTITION= "__reconciler_tracked_partition"; //$NON-NLS-1$
-
-
- /**
- * Internal listener class.
- */
- class InternalListener implements ITextInputListener, IDocumentListener, ITextListener,
- IDocumentPartitioningListener, IDocumentPartitioningListenerExtension {
-
- /*
- * @see ITextInputListener#inputDocumentAboutToBeChanged
- */
- public void inputDocumentAboutToBeChanged(IDocument oldDocument, IDocument newDocument) {
- if (oldDocument != null) {
- try {
-
- fViewer.removeTextListener(this);
- oldDocument.removeDocumentListener(this);
- oldDocument.removeDocumentPartitioningListener(this);
-
- oldDocument.removePositionUpdater(fPositionUpdater);
- oldDocument.removePositionCategory(fPositionCategory);
-
- } catch (BadPositionCategoryException x) {
- // should not happend for former input documents;
- }
- }
- }
-
- /*
- * @see ITextInputListener#inputDocumenChanged
- */
- public void inputDocumentChanged(IDocument oldDocument, IDocument newDocument) {
- if (newDocument != null) {
-
- newDocument.addPositionCategory(fPositionCategory);
- newDocument.addPositionUpdater(fPositionUpdater);
-
- newDocument.addDocumentPartitioningListener(this);
- newDocument.addDocumentListener(this);
- fViewer.addTextListener(this);
-
- setDocumentToDamagers(newDocument);
- setDocumentToRepairers(newDocument);
- processDamage(new Region(0, newDocument.getLength()), newDocument);
- }
- }
-
- /*
- * @see IDocumentPartitioningListener#documentPartitioningChanged
- */
- public void documentPartitioningChanged(IDocument document) {
- fDocumentPartitioningChanged= true;
- }
-
- /*
- * @see IDocumentPartitioningListenerExtension#documentPartitioningChanged
- */
- public void documentPartitioningChanged(IDocument document, IRegion changedRegion) {
- fDocumentPartitioningChanged= true;
- fChangedDocumentPartitions= changedRegion;
- }
-
- /*
- * @see IDocumentListener#documentAboutToBeChanged
- */
- public void documentAboutToBeChanged(DocumentEvent e) {
- try {
- int offset= e.getOffset() + e.getLength();
- fRememberedPosition= new TypedPosition(e.getDocument().getPartition(offset));
- e.getDocument().addPosition(fPositionCategory, fRememberedPosition);
- } catch (BadLocationException x) {
- // can not happen
- } catch (BadPositionCategoryException x) {
- // should not happen on input elements
- }
- }
-
- /*
- * @see IDocumentListener#documentChanged
- */
- public void documentChanged(DocumentEvent e) {
- try {
- e.getDocument().removePosition(fPositionCategory, fRememberedPosition);
- } catch (BadPositionCategoryException x) {
- // can not happen on input documents
- }
- }
-
- /*
- * @see ITextListener#textChanged
- */
- public void textChanged(TextEvent e) {
-
- DocumentEvent de= e.getDocumentEvent();
-
- if (de == null) {
-
- IDocument d= fViewer.getDocument();
- processDamage(new Region(0, d.getLength()), d);
-
- } else {
-
- IRegion damage= getDamage(de);
- if (damage != null)
- processDamage(damage, de.getDocument());
- }
-
- fDocumentPartitioningChanged= false;
- fChangedDocumentPartitions= null;
- }
- };
-
- /** The map of presentation damagers */
- private Map fDamagers;
- /** The map of presentation repairers */
- private Map fRepairers;
-
- private ITextViewer fViewer;
-
- private InternalListener fInternalListener= new InternalListener();
-
- private String fPositionCategory;
- private IPositionUpdater fPositionUpdater;
- private TypedPosition fRememberedPosition;
-
- private boolean fDocumentPartitioningChanged= false;
- private IRegion fChangedDocumentPartitions= null;
-
-
- /**
- * Creates a new presentation reconciler. There are no damagers or repairers
- * registered with this reconciler.
- */
- public CPresentationReconciler() {
- super();
- fPositionCategory= TRACKED_PARTITION + hashCode();
- fPositionUpdater= new DefaultPositionUpdater(fPositionCategory);
- }
-
- /**
- * Registers a given presentation damager for a particular content type.
- * If there is already a damager registered for this type, the new damager
- * is registered instead of the old one.
- *
- * @param damager the presentation damager to register, or null to remove an existing one
- * @param contentType the content type under which to register
- */
- public void setDamager(IPresentationDamager damager, String contentType) {
-
- Assert.isNotNull(contentType);
-
- if (fDamagers == null)
- fDamagers= new HashMap();
-
- if (damager == null)
- fDamagers.remove(contentType);
- else
- fDamagers.put(contentType, damager);
- }
-
- /**
- * Registers a given presentation repairer for a particular content type.
- * If there is already a repairer registered for this type, the new repairer
- * is registered instead of the old one.
- *
- * @param repairer the presentation repairer to register, or null to remove an existing one
- * @param contentType the content type under which to register
- */
- public void setRepairer(IPresentationRepairer repairer, String contentType) {
-
- Assert.isNotNull(contentType);
-
- if (fRepairers == null)
- fRepairers= new HashMap();
-
- if (repairer == null)
- fRepairers.remove(contentType);
- else
- fRepairers.put(contentType, repairer);
- }
-
- /*
- * @see IPresentationReconciler#install
- */
- public void install(ITextViewer viewer) {
- Assert.isNotNull(viewer);
-
- fViewer= viewer;
- fViewer.addTextInputListener(fInternalListener);
- }
-
- /*
- * @see IPresentationReconciler#uninstall
- */
- public void uninstall() {
- fViewer.removeTextInputListener(fInternalListener);
- }
-
- /*
- * @see IPresentationReconciler#getDamager
- */
- public IPresentationDamager getDamager(String contentType) {
-
- if (fDamagers == null)
- return null;
-
- return (IPresentationDamager) fDamagers.get(contentType);
- }
-
- /*
- * @see IPresentationReconciler#getRepairer
- */
- public IPresentationRepairer getRepairer(String contentType) {
-
- if (fRepairers == null)
- return null;
-
- return (IPresentationRepairer) fRepairers.get(contentType);
- }
-
- /**
- * Informs all registed damagers about the document on which they will work.
- *
- * @param document the document on which to work
- */
- private void setDocumentToDamagers(IDocument document) {
- if (fDamagers != null) {
- Iterator e= fDamagers.values().iterator();
- while (e.hasNext()) {
- IPresentationDamager damager= (IPresentationDamager) e.next();
- damager.setDocument(document);
- }
- }
- }
-
- /**
- * Informs all registed repairers about the document on which they will work.
- *
- * @param document the document on which to work
- */
- private void setDocumentToRepairers(IDocument document) {
- if (fRepairers != null) {
- Iterator e= fRepairers.values().iterator();
- while (e.hasNext()) {
- IPresentationRepairer repairer= (IPresentationRepairer) e.next();
- repairer.setDocument(document);
- }
- }
- }
-
- /**
- * Constructs a "repair description" for the given damage and returns
- * this description as a text presentation. For this, it queries the
- * partitioning of the damage region and asks for each partition an
- * appropriate presentation repairer to construct the "repair description"
- * for this partition.
- *
- * @param damage the damage to be repaired
- * @param document the document whose presentation must be repaired
- * @return the presentation repair descritption as text presentation
- */
- private TextPresentation createPresentation(IRegion damage, IDocument document) {
- try {
-
- TextPresentation presentation= new TextPresentation();
-
- ITypedRegion[] partitioning= document.computePartitioning(damage.getOffset(), damage.getLength());
- for (int i= 0; i < partitioning.length; i++) {
- ITypedRegion r= partitioning[i];
- IPresentationRepairer repairer= getRepairer(r.getType());
- if (repairer != null)
- repairer.createPresentation(presentation, r);
- }
-
- return presentation;
-
- } catch (BadLocationException x) {
- }
-
- return null;
- }
-
-
- /**
- * Checks for the first and the last affected partition and calls their damagers.
- * Invalidates everything from the start of the damage for the first partition
- * until the end of the damage for the last partition.
- *
- * @param e the event describing the document change
- * @return the damaged caused by the change
- */
- private IRegion getDamage(DocumentEvent e) {
-
- IRegion damage= null;
-
- try {
-
- ITypedRegion partition= e.getDocument().getPartition(e.getOffset());
- IPresentationDamager damager= getDamager(partition.getType());
- if (damager == null)
- return null;
-
- IRegion r= damager.getDamageRegion(partition, e, fDocumentPartitioningChanged);
-
- if (!fDocumentPartitioningChanged) {
- damage= r;
- } else {
-
- int damageEnd= getDamageEndOffset(e);
-
- int parititionDamageEnd= -1;
- if (fChangedDocumentPartitions != null)
- parititionDamageEnd= fChangedDocumentPartitions.getOffset() + fChangedDocumentPartitions.getLength();
-
- int end= Math.max(damageEnd, parititionDamageEnd);
-
- damage= end == -1 ? r : new Region(r.getOffset(), end - r.getOffset());
- }
-
- } catch (BadLocationException x) {
- }
-
- return damage;
- }
-
- /**
- * Returns the end offset of the damage. If a partition has been splitted by
- * the given document event also the second half of the original
- * partition must be considered. This is achieved by using the remembered
- * partition range.
- *
- * @param e the event describing the change
- * @return the damage end offset (excluding)
- * @exception BadLocationException if method accesses invalid offset
- */
- private int getDamageEndOffset(DocumentEvent e) throws BadLocationException {
-
- IDocument d= e.getDocument();
-
- int length= 0;
- if (e.getText() != null) {
- length= e.getText().length();
- if (length > 0)
- -- length;
- }
-
- ITypedRegion partition= d.getPartition(e.getOffset() + length);
- int endOffset= partition.getOffset() + partition.getLength();
- if (endOffset == e.getOffset())
- return -1;
-
- int end= fRememberedPosition.getOffset() + fRememberedPosition.getLength();
- if (endOffset < end)
- partition= d.getPartition(end);
-
- IPresentationDamager damager= getDamager(partition.getType());
- if (damager == null)
- return -1;
-
- IRegion r= damager.getDamageRegion(partition, e, fDocumentPartitioningChanged);
-
- return r.getOffset() + r.getLength();
- }
-
- /**
- * Processes the given damage.
- * @param damage the damage to be repaired
- * @param document the document whose presentation must be repaired
- */
- private void processDamage(IRegion damage, IDocument document) {
- if (damage != null && damage.getLength() > 0) {
- TextPresentation p= createPresentation(damage, document);
- if (p != null && !p.isEmpty())
- applyTextRegionCollection(p);
- }
- }
-
- /**
- * Applies the given text presentation to the text viewer the presentation
- * reconciler is installed on.
- *
- * @param presentation the text presentation to be applied to the text viewer
- */
- private void applyTextRegionCollection(TextPresentation presentation) {
- fViewer.changeTextPresentation(presentation, false);
- }
-}
-
-