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

   1 /*******************************************************************************
   2  * Copyright (c) 2009, 2013 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  *   Patrick Tasse - Updated for removal of context clone
  13  *******************************************************************************/
  14
  15 package org.eclipse.linuxtools.tmf.core.trace;
  16
  17 import org.eclipse.linuxtools.tmf.core.trace.location.ITmfLocation;
  18
  19 /**
  20  * The basic trace context structure in TMF. The purpose of the context is to
  21  * associate a trace location to an event at a specific rank (order).
  22  * <p>
  23  * The context should be sufficient to allow the trace to position itself so
  24  * that performing a trace read operation will yield the corresponding 'nth'
  25  * event.
  26  *
  27  * @version 1.0
  28  * @author Francois Chouinard
  29  *
  30  * @see ITmfLocation
  31  */
  32 public interface ITmfContext {
  33
  34     // ------------------------------------------------------------------------
  35     // Constants
  36     // ------------------------------------------------------------------------
  37
  38     /**
  39      * The unknown event rank
  40      */
  41     public long UNKNOWN_RANK = -1L;
  42
  43     // ------------------------------------------------------------------------
  44     // Getters
  45     // ------------------------------------------------------------------------
  46
  47     /**
  48      * @return the rank of the event at the context location
  49      */
  50     long getRank();
  51
  52     /**
  53      * @return the location of the event at the context rank
  54      * @since 3.0
  55      */
  56     ITmfLocation getLocation();
  57
  58     /**
  59      * @return indicates if the context rank is valid (!= UNKNOWN_RANK)
  60      */
  61     boolean hasValidRank();
  62
  63     // ------------------------------------------------------------------------
  64     // Operations
  65     // ------------------------------------------------------------------------
  66
  67     /**
  68      * @param location the new location
  69      * @since 3.0
  70      */
  71     void setLocation(ITmfLocation location);
  72
  73     /**
  74      * @param rank the new rank
  75      */
  76     void setRank(long rank);
  77
  78     /**
  79      * Increment the context rank
  80      */
  81     void increaseRank();
  82
  83     /**
  84      * Cleanup hook
  85      */
  86     void dispose();
  87
  88 }