Java tutorial
/* * Copyright (c) 2015 Eike Stepper (Berlin, Germany) 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: * Eike Stepper - initial API and implementation */ package org.eclipse.emf.cdo.ui.widgets; import org.eclipse.emf.cdo.CDOObject; import org.eclipse.emf.cdo.common.branch.CDOBranch; import org.eclipse.emf.cdo.common.branch.CDOBranchPoint; import org.eclipse.emf.cdo.common.branch.CDOBranchPointRange; import org.eclipse.emf.cdo.common.id.CDOID; import org.eclipse.emf.cdo.session.CDOSession; import org.eclipse.emf.cdo.spi.common.branch.CDOBranchUtil; import org.eclipse.emf.cdo.util.CDOUtil; import org.eclipse.emf.cdo.view.CDOStaleReferencePolicy; import org.eclipse.emf.cdo.view.CDOView; import org.eclipse.emf.cdo.view.CDOViewTargetChangedEvent; import org.eclipse.net4j.util.event.IEvent; import org.eclipse.net4j.util.event.IListener; import org.eclipse.net4j.util.lifecycle.ILifecycleEvent; import org.eclipse.net4j.util.lifecycle.ILifecycleEvent.Kind; import org.eclipse.emf.ecore.EObject; import org.eclipse.jface.viewers.ITreeViewerListener; import org.eclipse.jface.viewers.TreeExpansionEvent; import org.eclipse.jface.viewers.TreeViewer; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Scale; import java.util.HashSet; import java.util.Set; /** * @author Eike Stepper * @since 4.4 */ public class TimeSlider extends Scale implements IListener, ITreeViewerListener { private static final int MIN = 0; private static final int MAX = 100000; private static final double FACTOR = MAX - MIN; private final Set<CDOID> expandedIDs = new HashSet<CDOID>(); private long startTimeStamp; private long endTimeStamp; private long absoluteTimeWindowLength; private double stepSize; private long timeStamp; private CDOStaleReferencePolicy.DynamicProxy.Enhanced staleReferencePolicy; private CDOView view; private TreeViewer viewer; public TimeSlider(Composite parent, int style) { super(parent, style); setMinimum(MIN); setMaximum(MAX); setSelection(MAX); setPageIncrement(MAX - MIN); addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { long value = getSelection(); long timeStamp = startTimeStamp + Math.round(stepSize * value); setTimeStamp(timeStamp); if (viewer != null) { viewer.refresh(); setExpandedStates(); } } protected void setExpandedStates() { for (CDOID id : expandedIDs) { try { CDOObject object = view.getObject(id); viewer.setExpandedState(object, true); } catch (Exception ex) { // Ignore } } } }); } public final long getTimeStamp() { return timeStamp; } public void setTimeStamp(long timeStamp) { if (timeStamp == CDOBranchPoint.UNSPECIFIED_DATE) { timeStamp = endTimeStamp; } else if (timeStamp < startTimeStamp) { timeStamp = startTimeStamp; } else if (timeStamp > endTimeStamp) { timeStamp = endTimeStamp; } if (this.timeStamp != timeStamp) { this.timeStamp = timeStamp; final int newSelection = (int) ((timeStamp - startTimeStamp) / stepSize); Display display = getDisplay(); if (display == Display.getCurrent()) { if (getSelection() != newSelection) { setSelection(newSelection); } } else { display.asyncExec(new Runnable() { public void run() { if (getSelection() != newSelection) { setSelection(newSelection); } } }); } timeStampChanged(timeStamp); } } public void connect(CDOView view, TreeViewer viewer) { if (this.view != view) { disconnect(); if (view != null) { this.view = view; this.viewer = viewer; CDOBranchPointRange lifetime = null; if (this.viewer != null) { for (Object element : viewer.getExpandedElements()) { CDOID id = getID(element); if (id != null) { expandedIDs.add(id); } } this.viewer.addTreeListener(this); Object input = viewer.getInput(); if (input instanceof EObject) { lifetime = CDOUtil.getLifetime(CDOUtil.getCDOObject((EObject) input)); } } if (lifetime == null) { CDOSession session = view.getSession(); CDOBranch branch = view.getBranch(); CDOBranchPoint firstPoint = branch.getPoint(session.getRepositoryInfo().getCreationTime()); CDOBranchPoint lastPoint = branch.getHead(); lifetime = CDOBranchUtil.createRange(firstPoint, lastPoint); } startTimeStamp = lifetime.getStartPoint().getTimeStamp(); endTimeStamp = lifetime.getEndPoint().getTimeStamp(); if (endTimeStamp == CDOBranchPoint.UNSPECIFIED_DATE) { CDOSession session = view.getSession(); endTimeStamp = session.getLastUpdateTime(); } absoluteTimeWindowLength = endTimeStamp - startTimeStamp; stepSize = absoluteTimeWindowLength / FACTOR; setTimeStamp(view.getTimeStamp()); staleReferencePolicy = new CDOStaleReferencePolicy.DynamicProxy.Enhanced(view); view.addListener(this); setEnabled(true); } else { setEnabled(false); } } else if (this.view == null) { setEnabled(false); } } public void disconnect() { if (view != null) { if (staleReferencePolicy != null) { view.removeListener(this); staleReferencePolicy.dispose(); staleReferencePolicy = null; if (viewer != null) { expandedIDs.clear(); viewer.removeTreeListener(this); viewer = null; } } view = null; } } public void notifyEvent(IEvent event) { if (event instanceof CDOViewTargetChangedEvent) { CDOViewTargetChangedEvent e = (CDOViewTargetChangedEvent) event; setTimeStamp(e.getBranchPoint().getTimeStamp()); } else if (event instanceof ILifecycleEvent) { ILifecycleEvent e = (ILifecycleEvent) event; if (e.getKind() == Kind.ABOUT_TO_DEACTIVATE) { disconnect(); } } } public void treeExpanded(TreeExpansionEvent event) { CDOID id = getID(event.getElement()); if (id != null) { expandedIDs.add(id); } } public void treeCollapsed(TreeExpansionEvent event) { CDOID id = getID(event.getElement()); if (id != null) { expandedIDs.remove(id); } } @Override public void dispose() { disconnect(); super.dispose(); } protected void timeStampChanged(long timeStamp) { if (view != null) { view.setTimeStamp(timeStamp); } } @Override protected void checkSubclass() { // Allow overriding. } private CDOID getID(Object element) { if (element instanceof EObject) { CDOObject object = CDOUtil.getCDOObject((EObject) element, false); if (object != null) { return object.cdoID(); } } return null; } }