org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/tmf/core/trace/ITmfContext.java

   1 /*******************************************************************************
   2  * Copyright (c) 2009, 2010, 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  *   Francois Chouinard - Initial API and implementation
  11  *   Francois Chouinard - Updated as per TMF Trace Model 1.0
  12  *******************************************************************************/
  13
  14 package org.eclipse.linuxtools.tmf.core.trace;
  15
  16 /**
  17  * The basic trace context structure in TMF. The purpose of the context is to
  18  * associate a trace location to an event at a specific rank (order).
  19  * <p>
  20  * The context should be sufficient to allow the trace to position itself so
  21  * that performing a trace read operation will yield the corresponding 'nth'
  22  * event.
  23  *
  24  * @version 1.0
  25  * @author Francois Chouinard
  26  *
  27  * @see ITmfLocation
  28  */
  29 public interface ITmfContext {
  30
  31     // ------------------------------------------------------------------------
  32     // Constants
  33     // ------------------------------------------------------------------------
  34
  35     /**
  36      * The unknown event rank
  37      */
  38     public long UNKNOWN_RANK = -1L;
  39
  40     // ------------------------------------------------------------------------
  41     // Getters
  42     // ------------------------------------------------------------------------
  43
  44     /**
  45      * @return the rank of the event at the context location
  46      */
  47     public long getRank();
  48
  49     /**
  50      * @return the location of the event at the context rank
  51      */
  52     public ITmfLocation<? extends Comparable<?>> getLocation();
  53
  54     /**
  55      * @return indicates if the context rank is valid (!= UNKNOWN_RANK)
  56      */
  57     public boolean hasValidRank();
  58
  59     // ------------------------------------------------------------------------
  60     // Operations
  61     // ------------------------------------------------------------------------
  62
  63     /**
  64      * @param location the new location
  65      */
  66     public void setLocation(ITmfLocation<? extends Comparable<?>> location);
  67
  68     /**
  69      * @param rank the new rank
  70      */
  71     public void setRank(long rank);
  72
  73     /**
  74      * Increment the context rank
  75      */
  76     public void increaseRank();
  77
  78     /**
  79      * Cleanup hook
  80      */
  81     public void dispose();
  82
  83     /**
  84      * @return a clone of the context
  85      */
  86     public ITmfContext clone();
  87
  88 }