org.matsim.utils.eventsfilecomparison.EventFingerprint Class Reference

Public Member Functions
String	toString ()

Static Public Member Functions
static void	write (String filePath, EventFingerprint eventFingerprint)
static EventFingerprint	read (String fingerprintPath) throws IOException

Private Member Functions
	EventFingerprint (FloatList timeArray, Object2IntMap< String > eventTypeCounter, byte[] hash)

Private Attributes
final MessageDigest	digest

Detailed Description

Class holding reduced information about an events file. If two such fingerprint are different, one can conclude that the event files are semantically different.

The fingerprint is based on the following information:

• Array of all timestamps
• Counts of each event type
• Hash of string concatenation of all event strings

Note: Events with the same timestamp are allowed to occur in any order.

Definition at line 30 of file EventFingerprint.java.

Constructor & Destructor Documentation

EventFingerprint()

org.matsim.utils.eventsfilecomparison.EventFingerprint.EventFingerprint ( FloatList  timeArray, Object2IntMap< String >  eventTypeCounter, byte []  hash  )

private

Definition at line 46 of file EventFingerprint.java.

                                                                                                       {
        this.timeArray = timeArray;
        this.eventTypeCounter = eventTypeCounter;
        this.hash = hash;
        this.digest = null;
    }

Member Function Documentation

write()

static void org.matsim.utils.eventsfilecomparison.EventFingerprint.write ( String  filePath, EventFingerprint  eventFingerprint  )

static

Definition at line 65 of file EventFingerprint.java.

References org.matsim.core.utils.io.IOUtils.getFileUrl(), and org.matsim.core.utils.io.IOUtils.getOutputStream().

Referenced by org.matsim.core.events.EventsUtils.assertEqualEventsFingerprint(), org.matsim.core.events.EventsUtils.createAndCompareEventsFingerprint(), and org.matsim.core.events.EventsUtils.createEventsFingerprint().

                                                                                 {
        try (DataOutputStream dataOutputStream = new DataOutputStream(IOUtils.getOutputStream(IOUtils.getFileUrl(filePath), false))) {
            // Write header and version
            dataOutputStream.writeInt(EventFingerprint.HEADER_V1);

            // Write time array size and elements
            dataOutputStream.writeInt(eventFingerprint.timeArray.size());
            for (float time : eventFingerprint.timeArray) {
                dataOutputStream.writeFloat(time);
            }

            // Write event type counter map size and elements
            dataOutputStream.writeInt(eventFingerprint.eventTypeCounter.size());
            for (Map.Entry<String, Integer> entry : eventFingerprint.eventTypeCounter.entrySet()) {
                dataOutputStream.writeUTF(entry.getKey());
                dataOutputStream.writeInt(entry.getValue());
            }

            // Hash should always be computed at this point
            assert !Arrays.equals(eventFingerprint.hash, new byte[20]) : "Hash was not computed";

            // Write byte hash
            dataOutputStream.write(eventFingerprint.hash);

        } catch (IOException e) {
            throw new UncheckedIOException(e);
        }
    }

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read()

static EventFingerprint org.matsim.utils.eventsfilecomparison.EventFingerprint.read ( String  fingerprintPath ) throws IOException

static

Definition at line 94 of file EventFingerprint.java.

References org.matsim.core.utils.io.IOUtils.getFileUrl(), and org.matsim.core.utils.io.IOUtils.getInputStream().

Referenced by org.matsim.utils.eventsfilecomparison.EventsFileFingerprintComparator.compareFingerprints(), and org.matsim.utils.eventsfilecomparison.EventsFileFingerprintComparator.createFingerprintHandler().

                                                                                   {
        EventFingerprint eventFingerprint;

        try (DataInputStream dataInputStream = new DataInputStream(IOUtils.getInputStream(IOUtils.getFileUrl(fingerprintPath)))) {
            // Read header and version
            int fileHeader = dataInputStream.readInt();

            if (fileHeader != EventFingerprint.HEADER_V1) {
                throw new IllegalArgumentException("Invalid fingerprint file header");
            }

            // Read time array
            int timeArraySize = dataInputStream.readInt();
            FloatList timeArray = new FloatArrayList();
            for (int i = 0; i < timeArraySize; i++) {
                timeArray.add(dataInputStream.readFloat());
            }

            // Read event type counter map
            int eventTypeCounterSize = dataInputStream.readInt();
            Object2IntMap<String> eventTypeCounter = new Object2IntOpenHashMap<>();
            for (int i = 0; i < eventTypeCounterSize; i++) {
                String eventType = dataInputStream.readUTF();
                int count = dataInputStream.readInt();
                eventTypeCounter.put(eventType, count);
            }

            // Read string hash
            byte[] hash = dataInputStream.readNBytes(20);

            // Create EventFingerprint object
            eventFingerprint = new EventFingerprint(timeArray, eventTypeCounter, hash);
        }

        return eventFingerprint;
    }

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toString()

String org.matsim.utils.eventsfilecomparison.EventFingerprint.toString

(

)

Definition at line 158 of file EventFingerprint.java.

                             {
        return "EventFingerprint{" +
            "timeArray=" + timeArray.size() +
            ", eventTypeCounter=" + eventTypeCounter +
            ", hash=" + Arrays.toString(hash) +
            '}';
    }

Member Data Documentation

digest

final MessageDigest org.matsim.utils.eventsfilecomparison.EventFingerprint.digest

private

Builder for the hash.

Definition at line 44 of file EventFingerprint.java.

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The documentation for this class was generated from the following file:

• utils/eventsfilecomparison/EventFingerprint.java