org.eclipse.linuxtools.lttng2.ui/src/org/eclipse/linuxtools/internal/lttng2/ui/views/control/handlers/ChangeSessionStateHandler.java

   1 /**********************************************************************
   2  * Copyright (c) 2012 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Bernd Hufmann - Initial API and implementation
  11  **********************************************************************/
  12 package org.eclipse.linuxtools.internal.lttng2.ui.views.control.handlers;
  13
  14 import java.util.ArrayList;
  15 import java.util.Iterator;
  16 import java.util.List;
  17
  18 import org.eclipse.core.commands.ExecutionEvent;
  19 import org.eclipse.core.commands.ExecutionException;
  20 import org.eclipse.core.runtime.IProgressMonitor;
  21 import org.eclipse.core.runtime.IStatus;
  22 import org.eclipse.core.runtime.Status;
  23 import org.eclipse.core.runtime.jobs.Job;
  24 import org.eclipse.jface.viewers.ISelection;
  25 import org.eclipse.jface.viewers.StructuredSelection;
  26 import org.eclipse.linuxtools.internal.lttng2.core.control.model.TraceSessionState;
  27 import org.eclipse.linuxtools.internal.lttng2.ui.Activator;
  28 import org.eclipse.linuxtools.internal.lttng2.ui.views.control.ControlView;
  29 import org.eclipse.linuxtools.internal.lttng2.ui.views.control.messages.Messages;
  30 import org.eclipse.linuxtools.internal.lttng2.ui.views.control.model.impl.TraceSessionComponent;
  31 import org.eclipse.ui.IWorkbenchPage;
  32 import org.eclipse.ui.IWorkbenchWindow;
  33 import org.eclipse.ui.PlatformUI;
  34
  35 /**
  36  * <p>
  37  * Abstract command handler implementation to start or stop one or more trace sessions.
  38  * </p>
  39  *
  40  * @author Bernd Hufmann
  41  */
  42 abstract public class ChangeSessionStateHandler extends BaseControlViewHandler {
  43
  44     // ------------------------------------------------------------------------
  45     // Attributes
  46     // ------------------------------------------------------------------------
  47     /**
  48      * The list of session components the command is to be executed on.
  49      */
  50     protected List<TraceSessionComponent> fSessions = new ArrayList<TraceSessionComponent>();
  51
  52     // ------------------------------------------------------------------------
  53     // Accessors
  54     // ------------------------------------------------------------------------
  55
  56     /**
  57      * @return new required state.
  58      */
  59     abstract TraceSessionState getNewState();
  60
  61     // ------------------------------------------------------------------------
  62     // Operations
  63     // ------------------------------------------------------------------------
  64
  65     /**
  66      * Performs the state change on given session.
  67      *
  68      * @param session
  69      *            - a session which state is to be changed
  70      * @param monitor
  71      *            - a progress monitor
  72      * @throws ExecutionException
  73      *             If the command fails
  74      */
  75     abstract public void changeState(TraceSessionComponent session, IProgressMonitor monitor) throws ExecutionException;
  76
  77     /*
  78      * (non-Javadoc)
  79      * @see org.eclipse.core.commands.AbstractHandler#execute(org.eclipse.core.commands.ExecutionEvent)
  80      */
  81     @Override
  82     public Object execute(ExecutionEvent event) throws ExecutionException {
  83
  84         IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow();
  85
  86         if (window == null) {
  87             return false;
  88         }
  89
  90         fLock.lock();
  91         try {
  92
  93             final List<TraceSessionComponent> sessions = new ArrayList<TraceSessionComponent>();
  94             sessions.addAll(fSessions);
  95
  96             Job job = new Job(Messages.TraceControl_ChangeSessionStateJob) {
  97                 @Override
  98                 protected IStatus run(IProgressMonitor monitor) {
  99                     try {
 100                         for (Iterator<TraceSessionComponent> iterator = sessions.iterator(); iterator.hasNext();) {
 101
 102                             // Start all selected sessions
 103                             TraceSessionComponent session = iterator.next();
 104                             changeState(session, monitor);
 105
 106                             // Set Session state
 107                             session.setSessionState(getNewState());
 108                             session.fireComponentChanged(session);
 109                         }
 110                     } catch (ExecutionException e) {
 111                         return new Status(IStatus.ERROR, Activator.PLUGIN_ID, Messages.TraceControl_ChangeSessionStateFailure, e);
 112                     }
 113                     return Status.OK_STATUS;
 114                 }
 115             };
 116             job.setUser(true);
 117             job.schedule();
 118         } finally {
 119             fLock.unlock();
 120         }
 121         return null;
 122     }
 123
 124     /*
 125      * (non-Javadoc)
 126      * @see org.eclipse.core.commands.AbstractHandler#isEnabled()
 127      */
 128     @Override
 129     public boolean isEnabled() {
 130         // Get workbench page for the Control View
 131         IWorkbenchPage page = getWorkbenchPage();
 132         if (page == null) {
 133             return false;
 134         }
 135
 136         List<TraceSessionComponent> sessions = new ArrayList<TraceSessionComponent>(0);
 137
 138         // Check if one or more session are selected
 139         ISelection selection = page.getSelection(ControlView.ID);
 140         if (selection instanceof StructuredSelection) {
 141             StructuredSelection structered = ((StructuredSelection) selection);
 142             for (Iterator<?> iterator = structered.iterator(); iterator.hasNext();) {
 143                 Object element = iterator.next();
 144                 if (element instanceof TraceSessionComponent) {
 145                     // Add only TraceSessionComponents that are inactive and not destroyed
 146                     TraceSessionComponent session = (TraceSessionComponent) element;
 147                     if ((session.getSessionState() != getNewState()) && (!session.isDestroyed())) {
 148                         sessions.add(session);
 149                     }
 150                 }
 151             }
 152         }
 153         boolean isEnabled = !sessions.isEmpty();
 154         fLock.lock();
 155         try {
 156             fSessions = null;
 157             if (isEnabled) {
 158                 fSessions = sessions;
 159             }
 160         } finally {
 161             fLock.unlock();
 162         }
 163         return isEnabled;
 164     }
 165 }