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  * <b><u>ITmfContext</u></b>
  18  * <p>
  19  * The basic trace context structure in TMF. The purpose of the context is to
  20  * associate a trace location to an event of a specific rank (order).
  21  * <p>
  22  * The context should be sufficient to allow the trace to position itself so
  23  * that performing a trace read operation will yield the corresponding event.
  24  */
  25 public interface ITmfContext extends Cloneable {
  26
  27     // ------------------------------------------------------------------------
  28     // Constants
  29     // ------------------------------------------------------------------------
  30
  31     /**
  32      * The initial context event rank, before anything is read from the trace
  33      */
  34     public long INITIAL_RANK = -1L;
  35
  36     /**
  37      * The unknown event rank
  38      */
  39     public long UNKNOWN_RANK = -2L;
  40
  41     // ------------------------------------------------------------------------
  42     // Getters
  43     // ------------------------------------------------------------------------
  44
  45     /**
  46      * @return the rank of the event referred to by the context
  47      */
  48     public long getRank();
  49
  50     /**
  51      * @return the location of the event referred to by the context
  52      */
  53     public ITmfLocation<? extends Comparable<?>> getLocation();
  54
  55     /**
  56      * @return indicates if the context rank is valid (!= UNKNOWN_RANK)
  57      */
  58     public boolean hasValidRank();
  59
  60     // ------------------------------------------------------------------------
  61     // Operations
  62     // ------------------------------------------------------------------------
  63
  64     /**
  65      * @param location the new location
  66      */
  67     public void setLocation(ITmfLocation<? extends Comparable<?>> location);
  68
  69     /**
  70      * @param rank the new rank
  71      */
  72     public void setRank(long rank);
  73
  74     /**
  75      * Increment the context rank
  76      */
  77     public void increaseRank();
  78
  79     /**
  80      * Cleanup hook
  81      */
  82     public void dispose();
  83
  84     // ------------------------------------------------------------------------
  85     // Cloneable
  86     // ------------------------------------------------------------------------
  87
  88     /**
  89      * @return a clone of the context
  90      */
  91     public ITmfContext clone();
  92
  93 }