Package org.eclipse.jface.text.presentation

Source Code of org.eclipse.jface.text.presentation.PresentationReconciler$InternalListener

/*******************************************************************************
* Copyright (c) 2000, 2008 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
*     IBM Corporation - initial API and implementation
*******************************************************************************/

package org.eclipse.jface.text.presentation;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.eclipse.swt.custom.StyleRange;

import org.eclipse.core.runtime.Assert;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.BadPositionCategoryException;
import org.eclipse.jface.text.DefaultPositionUpdater;
import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.DocumentPartitioningChangedEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentExtension3;
import org.eclipse.jface.text.IDocumentListener;
import org.eclipse.jface.text.IDocumentPartitioningListener;
import org.eclipse.jface.text.IDocumentPartitioningListenerExtension;
import org.eclipse.jface.text.IDocumentPartitioningListenerExtension2;
import org.eclipse.jface.text.IPositionUpdater;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextInputListener;
import org.eclipse.jface.text.ITextListener;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.ITextViewerExtension5;
import org.eclipse.jface.text.ITypedRegion;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.TextEvent;
import org.eclipse.jface.text.TextPresentation;
import org.eclipse.jface.text.TextUtilities;
import org.eclipse.jface.text.TypedPosition;



/**
* Standard implementation of <code>IPresentationReconciler</code>. 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.
* <p>
* Usually, clients instantiate this class and configure it before using it.
* </p>
*/
public class PresentationReconciler implements IPresentationReconciler, IPresentationReconcilerExtension {

  /** Prefix of the name of the position category for tracking damage regions. */
  protected final static String TRACKED_PARTITION= "__reconciler_tracked_partition"; //$NON-NLS-1$


  /**
   * Internal listener class.
   */
  class InternalListener implements
      ITextInputListener, IDocumentListener, ITextListener,
      IDocumentPartitioningListener, IDocumentPartitioningListenerExtension, IDocumentPartitioningListenerExtension2 {

    /** Set to <code>true</code> if between a document about to be changed and a changed event. */
    private boolean fDocumentChanging= false;
    /**
     * The cached redraw state of the text viewer.
     * @since 3.0
     */
    private boolean fCachedRedrawState= true;

    /*
     * @see ITextInputListener#inputDocumentAboutToBeChanged(IDocument, IDocument)
     */
    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 happened for former input documents;
        }
      }
    }

    /*
     * @see ITextInputListener#inputDocumenChanged(IDocument, IDocument)
     */
    public void inputDocumentChanged(IDocument oldDocument, IDocument newDocument) {

      fDocumentChanging= false;
      fCachedRedrawState= true;

      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(IDocument)
     */
    public void documentPartitioningChanged(IDocument document) {
      if (!fDocumentChanging && fCachedRedrawState)
        processDamage(new Region(0, document.getLength()), document);
      else
        fDocumentPartitioningChanged= true;
    }

    /*
     * @see IDocumentPartitioningListenerExtension#documentPartitioningChanged(IDocument, IRegion)
     * @since 2.0
     */
    public void documentPartitioningChanged(IDocument document, IRegion changedRegion) {
      if (!fDocumentChanging && fCachedRedrawState) {
        processDamage(new Region(changedRegion.getOffset(), changedRegion.getLength()), document);
      } else {
        fDocumentPartitioningChanged= true;
        fChangedDocumentPartitions= changedRegion;
      }
    }

    /*
     * @see org.eclipse.jface.text.IDocumentPartitioningListenerExtension2#documentPartitioningChanged(org.eclipse.jface.text.DocumentPartitioningChangedEvent)
     * @since 3.0
     */
    public void documentPartitioningChanged(DocumentPartitioningChangedEvent event) {
      IRegion changedRegion= event.getChangedRegion(getDocumentPartitioning());
      if (changedRegion != null)
        documentPartitioningChanged(event.getDocument(), changedRegion);
    }

    /*
     * @see IDocumentListener#documentAboutToBeChanged(DocumentEvent)
     */
    public void documentAboutToBeChanged(DocumentEvent e) {

      fDocumentChanging= true;
      if (fCachedRedrawState) {
        try {
          int offset= e.getOffset() + e.getLength();
          ITypedRegion region= getPartition(e.getDocument(), offset);
          fRememberedPosition= new TypedPosition(region);
          e.getDocument().addPosition(fPositionCategory, fRememberedPosition);
        } catch (BadLocationException x) {
          // can not happen
        } catch (BadPositionCategoryException x) {
          // should not happen on input elements
        }
      }
    }

    /*
     * @see IDocumentListener#documentChanged(DocumentEvent)
     */
    public void documentChanged(DocumentEvent e) {
      if (fCachedRedrawState) {
        try {
          e.getDocument().removePosition(fPositionCategory, fRememberedPosition);
        } catch (BadPositionCategoryException x) {
          // can not happen on input documents
        }
      }
      fDocumentChanging= false;
    }

    /*
     * @see ITextListener#textChanged(TextEvent)
     */
    public void textChanged(TextEvent e) {

      fCachedRedrawState= e.getViewerRedrawState();
       if (!fCachedRedrawState)
         return;

       IRegion damage= null;
       IDocument document= null;

       if (e.getDocumentEvent() == null) {
         document= fViewer.getDocument();
         if (document != null)  {
           if (e.getOffset() == 0 && e.getLength() == 0 && e.getText() == null) {
            // redraw state change, damage the whole document
            damage= new Region(0, document.getLength());
           } else {
            IRegion region= widgetRegion2ModelRegion(e);
            try {
              String text= document.get(region.getOffset(), region.getLength());
              DocumentEvent de= new DocumentEvent(document, region.getOffset(), region.getLength(), text);
              damage= getDamage(de, false);
            } catch (BadLocationException x) {
            }
           }
         }
       } else  {
         DocumentEvent de= e.getDocumentEvent();
         document= de.getDocument();
         damage= getDamage(de, true);
       }

      if (damage != null && document != null)
        processDamage(damage, document);

      fDocumentPartitioningChanged= false;
      fChangedDocumentPartitions= null;
    }

    /**
     * Translates the given text event into the corresponding range of the viewer's document.
     *
     * @param e the text event
     * @return the widget region corresponding the region of the given event
     * @since 2.1
     */
    protected IRegion widgetRegion2ModelRegion(TextEvent e) {

      String text= e.getText();
      int length= text == null ? 0 : text.length();

      if (fViewer instanceof ITextViewerExtension5) {
        ITextViewerExtension5 extension= (ITextViewerExtension5) fViewer;
        return extension.widgetRange2ModelRange(new Region(e.getOffset(), length));
      }

      IRegion visible= fViewer.getVisibleRegion();
      IRegion region= new Region(e.getOffset() + visible.getOffset(), length);
      return region;
    }
  }

  /** The map of presentation damagers. */
  private Map fDamagers;
  /** The map of presentation repairers. */
  private Map fRepairers;
  /** The target viewer. */
  private ITextViewer fViewer;
  /** The internal listener. */
  private InternalListener fInternalListener= new InternalListener();
  /** The name of the position category to track damage regions. */
  private String fPositionCategory;
  /** The position updated for the damage regions' position category. */
  private IPositionUpdater fPositionUpdater;
  /** The positions representing the damage regions. */
  private TypedPosition fRememberedPosition;
  /** Flag indicating the receipt of a partitioning changed notification. */
  private boolean fDocumentPartitioningChanged= false;
  /** The range covering the changed partitioning. */
  private IRegion fChangedDocumentPartitions= null;
  /**
   * The partitioning used by this presentation reconciler.
   * @since 3.0
   */
  private String fPartitioning;

  /**
   * Creates a new presentation reconciler. There are no damagers or repairers
   * registered with this reconciler by default. The default partitioning
   * <code>IDocumentExtension3.DEFAULT_PARTITIONING</code> is used.
   */
  public PresentationReconciler() {
    super();
    fPartitioning= IDocumentExtension3.DEFAULT_PARTITIONING;
    fPositionCategory= TRACKED_PARTITION + hashCode();
    fPositionUpdater= new DefaultPositionUpdater(fPositionCategory);
  }

  /**
   * Sets the document partitioning for this presentation reconciler.
   *
   * @param partitioning the document partitioning for this presentation reconciler.
   * @since 3.0
   */
  public void setDocumentPartitioning(String partitioning) {
    Assert.isNotNull(partitioning);
    fPartitioning= partitioning;
  }

  /*
   * @see org.eclipse.jface.text.presentation.IPresentationReconcilerExtension#geDocumenttPartitioning()
   * @since 3.0
   */
  public String getDocumentPartitioning() {
    return fPartitioning;
  }

  /**
   * Registers the given presentation damager for a particular content type.
   * If there is already a damager registered for this type, the old damager
   * is removed first.
   *
   * @param damager the presentation damager to register, or <code>null</code> 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 the given presentation repairer for a particular content type.
   * If there is already a repairer registered for this type, the old repairer
   * is removed first.
   *
   * @param repairer the presentation repairer to register, or <code>null</code> 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(ITextViewer)
   */
  public void install(ITextViewer viewer) {
    Assert.isNotNull(viewer);

    fViewer= viewer;
    fViewer.addTextInputListener(fInternalListener);
   
    IDocument document= viewer.getDocument();
    if (document != null)
      fInternalListener.inputDocumentChanged(null, document);
  }

  /*
   * @see IPresentationReconciler#uninstall()
   */
  public void uninstall() {
    fViewer.removeTextInputListener(fInternalListener);

    // Ensure we uninstall all listeners
    fInternalListener.inputDocumentAboutToBeChanged(fViewer.getDocument(), null);
  }

  /*
   * @see IPresentationReconciler#getDamager(String)
   */
  public IPresentationDamager getDamager(String contentType) {

    if (fDamagers == null)
      return null;

    return (IPresentationDamager) fDamagers.get(contentType);
  }

  /*
   * @see IPresentationReconciler#getRepairer(String)
   */
  public IPresentationRepairer getRepairer(String contentType) {

    if (fRepairers == null)
      return null;

    return (IPresentationRepairer) fRepairers.get(contentType);
  }

  /**
   * Informs all registered damagers about the document on which they will work.
   *
   * @param document the document on which to work
   */
  protected 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 registered repairers about the document on which they will work.
   *
   * @param document the document on which to work
   */
  protected 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 the appropriate presentation repairer for
   * each partition 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 description as text presentation or
   *         <code>null</code> if the partitioning could not be computed
   */
  protected TextPresentation createPresentation(IRegion damage, IDocument document) {
    try {
      if (fRepairers == null || fRepairers.isEmpty()) {
        TextPresentation presentation= new TextPresentation(damage, 100);
        presentation.setDefaultStyleRange(new StyleRange(damage.getOffset(), damage.getLength(), null, null));
        return presentation;
      }

      TextPresentation presentation= new TextPresentation(damage, 1000);

      ITypedRegion[] partitioning= TextUtilities.computePartitioning(document, getDocumentPartitioning(), damage.getOffset(), damage.getLength(), false);
      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 affected by a
   * document event 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
   * @param optimize <code>true</code> if partition changes should be
   *        considered for optimization
   * @return the damaged caused by the change or <code>null</code> if
   *         computing the partitioning failed
   * @since 3.0
   */
  private IRegion getDamage(DocumentEvent e, boolean optimize) {
    int length= e.getText() == null ? 0 : e.getText().length();
   
    if (fDamagers == null || fDamagers.isEmpty()) {
      length= Math.max(e.getLength(), length);
      length= Math.min(e.getDocument().getLength() - e.getOffset(), length);
      return new Region(e.getOffset(), length);
    }

    boolean isDeletion= length == 0;
    IRegion damage= null;
    try {
      int offset= e.getOffset();
      if (isDeletion)
        offset= Math.max(0, offset - 1);
      ITypedRegion partition= getPartition(e.getDocument(), offset);
      IPresentationDamager damager= getDamager(partition.getType());
      if (damager == null)
        return null;

      IRegion r= damager.getDamageRegion(partition, e, fDocumentPartitioningChanged);

      if (!fDocumentPartitioningChanged && optimize && !isDeletion) {
        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 split 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= getPartition(d, e.getOffset() + length);
    int endOffset= partition.getOffset() + partition.getLength();
    if (endOffset == e.getOffset())
      return -1;

    int end= fRememberedPosition == null ? -1 : fRememberedPosition.getOffset() + fRememberedPosition.getLength();
    if (endOffset < end && end < d.getLength())
      partition= getPartition(d, 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)
        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);
  }

  /**
   * Returns the partition for the given offset in the given document.
   *
   * @param document the document
   * @param offset the offset
   * @return the partition
   * @throws BadLocationException if offset is invalid in the given document
   * @since 3.0
   */
  private ITypedRegion getPartition(IDocument document, int offset) throws BadLocationException {
    return TextUtilities.getPartition(document, getDocumentPartitioning(), offset, false);
  }
}
TOP

Related Classes of org.eclipse.jface.text.presentation.PresentationReconciler$InternalListener

TOP
Copyright © 2018 www.massapi.com. All rights reserved.
All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.