org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/internal/tmf/core/statesystem/backends/historytree/CoreNode.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.internal.tmf.core.statesystem.backends.historytree;
  14
  15 import java.nio.ByteBuffer;
  16
  17 /**
  18  * A Core node is a first-level node of a History Tree which is not a leaf node.
  19  *
  20  * It extends HTNode by adding support for child nodes, and also extensions.
  21  *
  22  * @author alexmont
  23  *
  24  */
  25 class CoreNode extends HTNode {
  26
  27     /* Nb. of children this node has */
  28     private int nbChildren;
  29
  30     /* Seq. numbers of the children nodes (size = MAX_NB_CHILDREN) */
  31     private int[] children;
  32
  33     /* Start times of each of the children (size = MAX_NB_CHILDREN) */
  34     private long[] childStart;
  35
  36     /* Seq number of this node's extension. -1 if none */
  37     private int extension;
  38
  39     /**
  40      * Initial constructor. Use this to initialize a new EMPTY node.
  41      *
  42      * @param tree
  43      *            The HistoryTree to which this node belongs
  44      * @param seqNumber
  45      *            The (unique) sequence number assigned to this particular node
  46      * @param parentSeqNumber
  47      *            The sequence number of this node's parent node
  48      * @param start
  49      *            The earliest timestamp stored in this node
  50      */
  51     CoreNode(HistoryTree tree, int seqNumber, int parentSeqNumber,
  52             long start) {
  53         super(tree, seqNumber, parentSeqNumber, start);
  54         this.nbChildren = 0;
  55
  56         /*
  57          * We instantiate the two following arrays at full size right away,
  58          * since we want to reserve that space in the node's header.
  59          * "this.nbChildren" will tell us how many relevant entries there are in
  60          * those tables.
  61          */
  62         this.children = new int[ownerTree.config.maxChildren];
  63         this.childStart = new long[ownerTree.config.maxChildren];
  64     }
  65
  66     @Override
  67     protected void readSpecificHeader(ByteBuffer buffer) {
  68         int i;
  69
  70         extension = buffer.getInt();
  71         nbChildren = buffer.getInt();
  72
  73         children = new int[ownerTree.config.maxChildren];
  74         for (i = 0; i < nbChildren; i++) {
  75             children[i] = buffer.getInt();
  76         }
  77         for (i = nbChildren; i < ownerTree.config.maxChildren; i++) {
  78             buffer.getInt();
  79         }
  80
  81         this.childStart = new long[ownerTree.config.maxChildren];
  82         for (i = 0; i < nbChildren; i++) {
  83             childStart[i] = buffer.getLong();
  84         }
  85         for (i = nbChildren; i < ownerTree.config.maxChildren; i++) {
  86             buffer.getLong();
  87         }
  88     }
  89
  90     @Override
  91     protected void writeSpecificHeader(ByteBuffer buffer) {
  92         int i;
  93
  94         buffer.putInt(extension);
  95         buffer.putInt(nbChildren);
  96
  97         /* Write the "children's seq number" array */
  98         for (i = 0; i < nbChildren; i++) {
  99             buffer.putInt(children[i]);
 100         }
 101         for (i = nbChildren; i < ownerTree.config.maxChildren; i++) {
 102             buffer.putInt(0);
 103         }
 104
 105         /* Write the "children's start times" array */
 106         for (i = 0; i < nbChildren; i++) {
 107             buffer.putLong(childStart[i]);
 108         }
 109         for (i = nbChildren; i < ownerTree.config.maxChildren; i++) {
 110             buffer.putLong(0);
 111         }
 112     }
 113
 114     int getNbChildren() {
 115         return nbChildren;
 116     }
 117
 118     int getChild(int index) {
 119         return children[index];
 120     }
 121
 122     int getLatestChild() {
 123         return children[nbChildren - 1];
 124     }
 125
 126     long getChildStart(int index) {
 127         return childStart[index];
 128     }
 129
 130     long getLatestChildStart() {
 131         return childStart[nbChildren - 1];
 132     }
 133
 134     int getExtensionSequenceNumber() {
 135         return extension;
 136     }
 137
 138     /**
 139      * Tell this node that it has a new child (Congrats!)
 140      *
 141      * @param childNode
 142      *            The SHTNode object of the new child
 143      */
 144     void linkNewChild(CoreNode childNode) {
 145         assert (this.nbChildren < ownerTree.config.maxChildren);
 146
 147         this.children[nbChildren] = childNode.getSequenceNumber();
 148         this.childStart[nbChildren] = childNode.getNodeStart();
 149         this.nbChildren++;
 150     }
 151
 152     @Override
 153     protected byte getNodeType() {
 154         return 1;
 155     }
 156
 157     @Override
 158     protected int getTotalHeaderSize() {
 159         int specificSize;
 160         specificSize = 4 /* 1x int (extension node) */
 161                 + 4 /* 1x int (nbChildren) */
 162
 163                 /* MAX_NB * int ('children' table) */
 164                 + 4 * ownerTree.config.maxChildren
 165
 166                 /* MAX_NB * Timevalue ('childStart' table) */
 167                 + 8 * ownerTree.config.maxChildren;
 168
 169         return getCommonHeaderSize() + specificSize;
 170     }
 171
 172     @Override
 173     protected String toStringSpecific() {
 174         /* Only used for debugging, shouldn't be externalized */
 175         return "Core Node, " + nbChildren + " children, "; //$NON-NLS-1$ //$NON-NLS-2$
 176     }
 177
 178 }