fiftyone.mobile.detection.entities.stream.NodeV32 Maven / Gradle / Ivy
/* *********************************************************************
* This Source Code Form is copyright of 51Degrees Mobile Experts Limited.
* Copyright © 2017 51Degrees Mobile Experts Limited, 5 Charlotte Close,
* Caversham, Reading, Berkshire, United Kingdom RG4 7BY
*
* This Source Code Form is the subject of the following patents and patent
* applications, owned by 51Degrees Mobile Experts Limited of 5 Charlotte
* Close, Caversham, Reading, Berkshire, United Kingdom RG4 7BY:
* European Patent No. 2871816;
* European Patent Application No. 17184134.9;
* United States Patent Nos. 9,332,086 and 9,350,823; and
* United States Patent Application No. 15/686,066.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0.
*
* If a copy of the MPL was not distributed with this file, You can obtain
* one at http://mozilla.org/MPL/2.0/.
*
* This Source Code Form is "Incompatible With Secondary Licenses", as
* defined by the Mozilla Public License, v. 2.0.
* ********************************************************************* */
package fiftyone.mobile.detection.entities.stream;
import fiftyone.mobile.detection.IndirectDataset;
import fiftyone.mobile.detection.factories.NodeFactoryShared;
import fiftyone.mobile.detection.readers.BinaryReader;
import fiftyone.properties.DetectionConstants;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/**
* Represents a Node which can be used with the Stream data set. NumericChidren
* and RankedSignatureIndexes are not loaded into memory when the entity is
* constructed, they're only loaded from the data source when requested.
*
* Objects of this class should not be created directly as they are part of the
* internal logic.
*/
public class NodeV32 extends Node {
/**
* A list of all the signature indexes that relate to this node.
*/
@SuppressWarnings("VolatileArrayField")
private volatile List rankedSignatureIndexes;
/**
* Constructs a new instance of NodeV32.
*
* @param dataSet The data set the node is contained within.
* @param offset The offset in the data structure to the node.
* @param reader Reader connected to the source data structure and
* positioned to start reading.
* @throws java.io.IOException if there was a problem accessing data file.
*/
public NodeV32(IndirectDataset dataSet,
int offset, BinaryReader reader) throws IOException {
super(dataSet, offset, reader);
super.rankedSignatureCount = reader.readUInt16();
super.children = NodeFactoryShared.readNodeIndexesV32(
dataSet,
reader,
(int)(offset + reader.getPos() - nodeStartStreamPosition),
childrenCount);
super.numericChildrenPosition = reader.getPos();
}
/**
* @return a list of all the signature indexes that relate to this node.
* @throws java.io.IOException if there was a problem accessing data file.
*/
@Override
@SuppressWarnings("DoubleCheckedLocking")
public List getRankedSignatureIndexes() throws IOException {
List localRankedSignatureIndexes = rankedSignatureIndexes;
if (localRankedSignatureIndexes == null) {
synchronized (this) {
localRankedSignatureIndexes = rankedSignatureIndexes;
if (localRankedSignatureIndexes == null) {
rankedSignatureIndexes = localRankedSignatureIndexes =
getRankedSignatureIndexesAsArray();
}
}
}
return localRankedSignatureIndexes;
}
//
private int getRankedSignatureIndexValue() throws IOException {
BinaryReader reader = pool.getReader();
try {
// Position the reader after the numeric children.
reader.setPos(numericChildrenPosition + (
( DetectionConstants.SIZE_OF_SHORT +
DetectionConstants.SIZE_OF_INT ) *
getNumericChildrenLength()));
return reader.readInt32();
} finally {
pool.release(reader);
}
}
/**
* Gets the ranked signature indexes array for the node.
*
* @return An array of length _rankedSignatureCount filled with ranked
* signature indexes.
*/
private List getRankedSignatureIndexesAsArray() throws IOException {
// RankedSignatureIndexes (RSI).
List rsi = null;
if (rankedSignatureCount == 0) {
rsi = new ArrayList(0);
} else {
int rankedSignatureValue = getRankedSignatureIndexValue();
if (rankedSignatureCount == 1) {
rsi = new ArrayList();
rsi.add(rankedSignatureValue);
} else {
rsi = dataSet.getNodeRankedSignatureIndexes().getRange(
rankedSignatureValue, rankedSignatureCount);
}
}
return rsi;
}
//
}