package org.apidesign.javabeans.with;

 import java.util.ArrayList;

 import java.util.List;

 public abstract class AbstractHighlightsContainer implements HighlightsContainer {

     private List<HighlightsChangeListener> listeners = new ArrayList<HighlightsChangeListener>();

     protected AbstractHighlightsContainer() {

     }

     public abstract HighlightsSequence getHighlights(int startOffset, int endOffset);

     public final void addHighlightsChangeListener(HighlightsChangeListener listener) {

         synchronized (listeners) {

             listeners.add(listener);

         }

     }

     public final void removeHighlightsChangeListener(HighlightsChangeListener listener) {

         synchronized (listeners) {

             listeners.remove(listener);

         }

     }

     protected final void fireHighlightsChange(int changeStartOffset, int changeEndOffset) {

         List<HighlightsChangeListener> targets;

         synchronized (listeners) {

             targets = new ArrayList<HighlightsChangeListener>(listeners);

         }

         if (targets.size() > 0) {

             HighlightsChangeEvent evt = new HighlightsChangeEvent(this, changeStartOffset, changeEndOffset);

             for (HighlightsChangeListener l : targets) {

                 l.highlightChanged(evt);

             }

         }

     }

 }