package ccw.editors.clojure;
import java.util.ArrayList;
import java.util.List;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jdt.core.ISourceRange;
import org.eclipse.jface.viewers.ISelectionChangedListener;
import org.eclipse.jface.viewers.SelectionChangedEvent;
public class SelectionHistory {
private List fHistory;
private IClojureEditor fEditor;
private ISelectionChangedListener fSelectionListener;
private int fSelectionChangeListenerCounter;
public SelectionHistory(IClojureEditor editor) {
Assert.isNotNull(editor);
fEditor= editor;
fHistory= new ArrayList(3);
fSelectionListener= new ISelectionChangedListener() {
public void selectionChanged(SelectionChangedEvent event) {
if (fSelectionChangeListenerCounter == 0)
flush();
}
};
fEditor.getSelectionProvider().addSelectionChangedListener(fSelectionListener);
}
public boolean isEmpty() {
return fHistory.isEmpty();
}
public void remember(ISourceRange range) {
// System.out.println("asked to remember range:" + range);
fHistory.add(range);
// fHistoryAction.update(); TODO correctement
}
public ISourceRange getLast() {
if (isEmpty())
return null;
int size= fHistory.size();
ISourceRange result= (ISourceRange)fHistory.remove(size - 1);
// fHistoryAction.update(); TODO correctement
return result;
}
public void flush() {
if (fHistory.isEmpty())
return;
fHistory.clear();
// fHistoryAction.update(); TODO correctement
}
public void ignoreSelectionChanges() {
fSelectionChangeListenerCounter++;
}
public void listenToSelectionChanges() {
fSelectionChangeListenerCounter--;
}
public void dispose() {
fEditor.getSelectionProvider().removeSelectionChangedListener(fSelectionListener);
}
}