org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/tmf/core/statesystem/IStateChangeInput.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012 Ericsson
   3  * Copyright (c) 2010, 2011 École Polytechnique de Montréal
   4  * Copyright (c) 2010, 2011 Alexandre Montplaisir <alexandre.montplaisir@gmail.com>
   5  *
   6  * All rights reserved. This program and the accompanying materials are
   7  * made available under the terms of the Eclipse Public License v1.0 which
   8  * accompanies this distribution, and is available at
   9  * http://www.eclipse.org/legal/epl-v10.html
  10  *
  11  *******************************************************************************/
  12
  13 package org.eclipse.linuxtools.tmf.core.statesystem;
  14
  15 import org.eclipse.linuxtools.tmf.core.event.ITmfEvent;
  16 import org.eclipse.linuxtools.tmf.core.trace.ITmfTrace;
  17
  18 /**
  19  * This is the interface used to define the "state change input", which is the
  20  * main type of input that goes in the state system.
  21  *
  22  * Usually a state change input, also called "state provider" is the piece of
  23  * the pipeline which converts trace events to state changes.
  24  *
  25  * @version 1.0
  26  * @author Alexandre Montplaisir
  27  */
  28 public interface IStateChangeInput {
  29
  30     /**
  31      * Get the trace with which this state input plugin is associated.
  32      *
  33      * @return The associated trace
  34      */
  35     public ITmfTrace getTrace();
  36
  37     /**
  38      * Return the start time of this "state change input", which is normally the
  39      * start time of the originating trace (or it can be the time of the first
  40      * state-changing event).
  41      *
  42      * @return The start time
  43      */
  44     public long getStartTime();
  45
  46     /**
  47      * Method for the input plugin to specify which type of events it expects.
  48      * This will guarantee that all events it receives via processEvent() are
  49      * indeed of the given type, so it should be safe to cast to that type.
  50      *
  51      * @return An example event of the expected class, which implements
  52      *         ITmfEvent. The contents of that event doesn't matter, only the
  53      *         class will be checked.
  54      */
  55     public ITmfEvent getExpectedEventType();
  56
  57     /**
  58      * Assign the target state system where this SCI will insert its state
  59      * changes. Because of dependencies issues, this can normally not be done at
  60      * the constructor.
  61      *
  62      * This needs to be called before .run()!
  63      *
  64      * @param ssb
  65      *            Target state system for the state changes generated by this
  66      *            input plugin
  67      */
  68     public void assignTargetStateSystem(IStateSystemBuilder ssb);
  69
  70     /**
  71      * Send an event to this input plugin for processing. The implementation
  72      * should check the contents, and call the state-modifying methods of its
  73      * IStateSystemBuilder object accordingly.
  74      *
  75      * @param event
  76      *            The event (which should be safe to cast to the
  77      *            expectedEventType) that has to be processed.
  78      */
  79     public void processEvent(ITmfEvent event);
  80
  81     /**
  82      * Indicate to the state history building process that we are done (for now),
  83      * and that it should close its current history.
  84      */
  85     public void dispose();
  86 }