tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/trace/ITmfTraceWithPreDefinedEvents.java

   1 /*******************************************************************************
   2  * Copyright (c) 2014 École Polytechnique de Montréal, 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  *   Geneviève Bastien - Initial API and implementation
  11  *   Matthew Khouzam - Initial API and implementation
  12  *******************************************************************************/
  13
  14 package org.eclipse.tracecompass.tmf.core.trace;
  15
  16 import java.util.Set;
  17
  18 import org.eclipse.jdt.annotation.NonNullByDefault;
  19 import org.eclipse.tracecompass.tmf.core.event.ITmfEventType;
  20
  21 /**
  22  * This interface should be implemented by all trace classes who have a way to
  23  * know in advance what events it may contain. It allows analyses and other
  24  * external components to ask the list of events for the trace might contain.
  25  *
  26  * The methods from this interface will typically be called to determine whether
  27  * or not it is worth reading a trace. If we can know in advance that a trace
  28  * does not contain the events required by an analysis, then the analysis will
  29  * not be run. So the response should not involve having to actually read the
  30  * trace.
  31  *
  32  * @author Geneviève Bastien
  33  * @author Matthew Khouzam
  34  */
  35 @NonNullByDefault
  36 public interface ITmfTraceWithPreDefinedEvents {
  37
  38     /**
  39      * Return a set of event types declared in the trace, without actually
  40      * reading the trace. This method can be called before reading a trace but
  41      * after it is initialized, in order to compare this set with a set of
  42      * events that a request handles, to determine whether or not it is worth
  43      * reading the trace.
  44      *
  45      * Some trace types have ways to determine the events that were traced
  46      * without having to read the whole trace and this is what this method will
  47      * query. The presence of an event in the returned set does not guarantee
  48      * that an event with this name actually happened during this trace, only
  49      * that it can be there.
  50      *
  51      * The set should be immutable. Destructive set operations should be
  52      * performed on a copy of this set.A helper class
  53      * {@link TmfEventTypeCollectionHelper} will provide ways of working with
  54      * this data structure.
  55      *
  56      * @return The set of events that might be present in the trace
  57      */
  58     Set<? extends ITmfEventType> getContainedEventTypes();
  59
  60 }