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Commit 18f259d0 authored by Brutzman, Don's avatar Brutzman, Don
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change epochLvc to java.time.Instant

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src/edu/nps/moves/dis7/utilities/DisTime.java
+ 90
− 29
View file @ 18f259d0
......@@ -9,6 +9,7 @@ import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.time.*;
import java.util.*;
/**
......@@ -75,7 +76,7 @@ import java.util.*;
* rollover, instead getting only a monotonically increasing timestamp value.</p>
*
* <p><b>TODO: timestamp normalization to an initial reference time.</b>
* Functionality is needed to define a shared common time origin (epoch) and also to
* Functionality is needed to define a shared common time origin (epochLvc) and also to
* precisely adjust stream timestamps when coordinating recorded PDU playback within LVC applications.
* We think the ability to "start at time 0.0", or normalizing initial time to zero
* for a recorded PDU stream, is actually a pretty common use case.
......@@ -121,11 +122,18 @@ public class DisTime
*/
private static boolean hostClockSynchronized = true;
/** Reference starting time for current timestamps
/** Whether to apply epochLvc as baseline starting time for DIS timestamps, enabling time normalization of LVC streams.
* Distinct from Unix timestamp EPOCH.
* <a href="https://en.wikipedia.org/wiki/Epoch_(computing)" target="_blank">https://en.wikipedia.org/wiki/Epoch_(computing)</a>.
*/
private static int epoch = 0;
private static boolean applyEpochLvc = false;
/** Reference starting time for current DIS timestamps, enabling time normalization of LVC streams.
* Distinct from Unix timestamp EPOCH.
* <a href="https://en.wikipedia.org/wiki/Epoch_(computing)" target="_blank">https://en.wikipedia.org/wiki/Epoch_(computing)</a>.
*/
private static Instant epochLvc = Instant.now(); // initialized at start
/** We can marshal the PDU with a timestamp set to any of several styles.
* Remember, you MUST set a timestamp. DIS will regard multiple packets sent
* with the same timestamp as duplicates and may discard them.
......@@ -141,8 +149,11 @@ public class DisTime
/** calendar instance */
private static GregorianCalendar calendar;
// private LocalDateTime todayDateTime = new LocalDateTime();
// private Instant todayInstant = new Instant();
private static String dateFormatPattern = "HH:mm:ss";
private static String dateFormatPattern = "yyyy-mm-dd";
private static String timeFormatPattern = "HH:mm:ss";
// public static DisTime disTime = null;
......@@ -167,7 +178,7 @@ public class DisTime
/**
* For current system time, returns the number of DIS time units since the top of the hour, or else
* number of DIS time units since previously set epoch timestamp (for time-zero-based streams).
* number of DIS time units since previously set epochLvc timestamp (for time-zero-based streams).
* Note that there are 2^31-1 DIS time units per hour.
* @return integer DIS time units since the start of the hour.
*/
......@@ -194,13 +205,14 @@ public class DisTime
double differenceValue;
int differenceTimestamp;
if (epoch == 0)
if (!hasEpochLvc())
{
timeDifferenceMsec = currentTime - topOfHourMsec;
}
else // normalized time reference having 00:00 at start
{
timeDifferenceMsec = currentTime - epoch;
Duration d = java.time.Duration.between(epochLvc, Instant.now());
timeDifferenceMsec = d.toMillis();
}
differenceValue = (timeDifferenceMsec / (3600.0 * 1000.0)) * Integer.MAX_VALUE;
differenceTimestamp = (int) differenceValue;
......@@ -292,7 +304,7 @@ public class DisTime
/**
* Convert timestamp value to string for logging and diagnostics,
* taking into account epoch and TimeStampStyle (DIS absolute/relative, Unix or Year).
* taking into account epochLvc and TimeStampStyle (DIS absolute/relative, Unix or Year).
* TODO consider different formats for different timestampStyle values.
* @param timestamp value in milliseconds
* @see GregorianCalendar
......@@ -302,13 +314,13 @@ public class DisTime
public static String convertToString(int timestamp)
{
GregorianCalendar newCalendar = new GregorianCalendar();
DateFormat formatter = new SimpleDateFormat(dateFormatPattern);
DateFormat formatter = new SimpleDateFormat(dateFormatPattern + " " + timeFormatPattern);
if ((timestampStyle == TimestampStyle.IEEE_ABSOLUTE) ||
(timestampStyle == TimestampStyle.IEEE_RELATIVE))
{
// if epoch is not set, this is regular DIS value
newCalendar.setTimeInMillis(timestamp - epoch);
// if epochLvc is not set, this is regular DIS value
newCalendar.setTimeInMillis(timestamp); // - epochLvc
return formatter.format(newCalendar.getTime());
}
else if (timestampStyle == TimestampStyle.UNIX) // TODO
......@@ -401,46 +413,95 @@ public class DisTime
return hostClockSynchronized;
}
/** Set epoch using current time for zero-based clock, meaning timestamps are normalized to "time zero" of simulation
/** Reset epochLvc using current time for zero-based clock, meaning timestamps are normalized to "time zero" of simulation
* as initial starting time
*/
public static void setEpochCurrentTimestamp()
public static void setEpochLvcNow()
{
setEpoch(getCurrentDisAbsoluteTimestamp());
applyEpochLvc = true;
setEpochLvc(Instant.now()); // getCurrentDisAbsoluteTimestamp());
}
/** Set initial timestamp as epoch for zero-based clock, meaning timestamps normalized to 0 as initial starting time
* @param initialTimestamp first timestamp in series, considered time zero
/** Set Instant value as epochLvc for zero-based clock, meaning timestamps normalized to 0 at that initial starting time
* @param newEpoch Instant corresponding to first PDU in series, considered time zero
*/
public static void setEpoch(int initialTimestamp)
public static void setEpochLvc(java.time.Instant newEpoch)
{
epoch = initialTimestamp;
epochLvc = newEpoch;
}
/** Get initial timestamp for zero-based clock, meaning all timestamps are measured with resepct to given starting time
/** Get initial timestamp for zero-based clock, meaning all timestamps are measured with respect to given starting time
* @return whether localhost is synchronized to time reference
*/
public static int getEpoch()
public static java.time.Instant getEpochLvc()
{
return epochLvc;
}
/** Whether epochLvc is currently applied
* @return whether epochLvc is active
*/
public static boolean hasEpochLvc()
{
return applyEpochLvc;
}
/** Reset epochLvc so it is no longer active
*/
public static void clearEpochLvc()
{
return epoch;
applyEpochLvc = false;
}
private void sleep(long ms) {
sleep(ms, 0);
}
private void sleep(long ms, int ns)
{
try {
Thread.sleep(ms, ns);
}
catch (InterruptedException ex) {}
}
/** Self-test for basic smoke testing */
private void selfTest()
{
DisTime.initializeTimestampMethod();
System.out.println("=== legacy java.util.Date, calendar methods ===");
System.out.println("DisTime.getTimestampStyle() = " + DisTime.getTimestampStyle());
System.out.println(" = " + dateFormatPattern);
System.out.println("patterns = " + dateFormatPattern + " " + timeFormatPattern);
int initialTimestamp = DisTime.getTimestamp();
System.out.println("DisTime.getTimestamp() initialTimestamp = " + convertToString(initialTimestamp) + " = " + Integer.toUnsignedString(initialTimestamp) + " = " + initialTimestamp + " (unsigned vs signed output)");
System.out.println("DisTime.getTimestamp() = " + convertToString(DisTime.getTimestamp()) + " = " + Integer.toUnsignedString(DisTime.getTimestamp()) + " = " + DisTime.getTimestamp()+ " (unsigned vs signed output)");
System.out.println("DisTime.getCurrentDisAbsoluteTimestamp() = " + convertToString(DisTime.getCurrentDisAbsoluteTimestamp()) + " = " + Integer.toUnsignedString(DisTime.getCurrentDisAbsoluteTimestamp()));
System.out.println("DisTime.getCurrentDisRelativeTimestamp() = " + convertToString(DisTime.getCurrentDisRelativeTimestamp()) + " = " + Integer.toUnsignedString(DisTime.getCurrentDisRelativeTimestamp()));
System.out.println("DisTime.getCurrentDisTimeUnitsSinceTopOfHour() = " + convertToString(DisTime.getCurrentDisTimeUnitsSinceTopOfHour()) + " = " + DisTime.getCurrentDisTimeUnitsSinceTopOfHour());
System.out.println("DisTime.getEpoch() = " + convertToString(DisTime.getEpoch()) + " = " + DisTime.getEpoch());
setEpochCurrentTimestamp();
System.out.println("DisTime.setEpochCurrentTimestamp();");
System.out.println("DisTime.getEpoch() = " + convertToString(DisTime.getEpoch()) + " = " + DisTime.getEpoch());
System.out.println("DisTime.getCurrentDisTimeUnitsSinceTopOfHour() = " + convertToString(DisTime.getCurrentDisTimeUnitsSinceTopOfHour()) + " = " + DisTime.getCurrentDisTimeUnitsSinceTopOfHour());
}
System.out.println();
System.out.println("=== modern java.time methods ===");
System.out.println("note that LocalDateTime is current time zone while default Instant is UTC with time zone Z appended");
System.out.println("java.time.LocalDateTime.now(), Instant.now() = " + java.time.LocalDateTime.now() + ", " + java.time.Instant.now());
System.out.println("java.time.LocalDateTime.now(), Instant.now() = " + java.time.LocalDateTime.now() + ", " + java.time.Instant.now());
System.out.println("java.time.LocalDateTime.now(), Instant.now() = " + java.time.LocalDateTime.now() + ", " + java.time.Instant.now());
System.out.println("sleep for 1000 msec...");
sleep(1000l); // hold on a second
System.out.println("java.time.LocalDateTime.now(), Instant.now() = " + java.time.LocalDateTime.now() + ", " + java.time.Instant.now());
System.out.println("java.time.LocalDateTime.now(), Instant.now() = " + java.time.LocalDateTime.now() + ", " + java.time.Instant.now());
System.out.println("java.time.LocalDateTime.now(), Instant.now() = " + java.time.LocalDateTime.now() + ", " + java.time.Instant.now());
System.out.println("DisTime.hasEpochLvc() = " + DisTime.hasEpochLvc());
System.out.println("DisTime.setEpochLvcNow()...");
setEpochLvcNow();
System.out.println("DisTime.hasEpochLvc(), = " + DisTime.hasEpochLvc());
Instant now = Instant.now();
System.out.println("DisTime.getEpochLvc(), Instant.now(), duration = " + DisTime.getEpochLvc() + ", " + now + ", " +
java.time.Duration.between(getEpochLvc(), now).toMillis() + " msec");
System.out.println("sleep for 1000 msec...");
sleep(1000l); // hold on a second
now = Instant.now();
System.out.println("DisTime.getEpochLvc(), Instant.now(), duration = " + DisTime.getEpochLvc() + ", " + now + ", " +
java.time.Duration.between(getEpochLvc(), now).toMillis() + " msec");
// System.out.println("DisTime.getCurrentDisTimeUnitsSinceTopOfHour() = " + convertToString(DisTime.getCurrentDisTimeUnitsSinceTopOfHour()) + " = " + DisTime.getCurrentDisTimeUnitsSinceTopOfHour());
}
/**
* Main method for testing.
......
src/edu/nps/moves/dis7/utilities/DisTimeLog.txt
+ 24
− 10
View file @ 18f259d0
......@@ -7,15 +7,29 @@ Compiling 1 source file to C:\x3d-github\open-dis7-java\build\classes
compile-single:
run-single:
*** DisTime.main() self test started...
=== legacy java.util.Date, calendar methods ===
DisTime.getTimestampStyle() = IEEE_ABSOLUTE
DisTime.getTimestamp() initialTimestamp = 08:52:40 = 1011160571 = 1011160571 (unsigned vs signed output)
DisTime.getTimestamp() = 08:52:59 = 1011180853 = 1011180853 (unsigned vs signed output)
DisTime.getCurrentDisAbsoluteTimestamp() = 08:53:00 = 1011180853
DisTime.getCurrentDisRelativeTimestamp() = 08:53:03 = 1011184430
DisTime.getCurrentDisTimeUnitsSinceTopOfHour() = 12:26:32 = 505592215
DisTime.getEpoch() = 16:00:00 = 0
DisTime.setEpochCurrentTimestamp();
DisTime.getEpoch() = 16:00:00 = 1011184431
DisTime.getCurrentDisTimeUnitsSinceTopOfHour() = 19:38:19 = 2147483647
patterns = yyyy-mm-dd HH:mm:ss
DisTime.getTimestamp() initialTimestamp = 1970-10-02 08:10:52 = 144652113 = 144652113 (unsigned vs signed output)
DisTime.getTimestamp() = 1970-11-02 08:11:01 = 144662849 = 144662849 (unsigned vs signed output)
DisTime.getCurrentDisAbsoluteTimestamp() = 1970-11-02 08:11:02 = 144662849
DisTime.getCurrentDisRelativeTimestamp() = 1970-11-02 08:11:02 = 144662848
DisTime.getCurrentDisTimeUnitsSinceTopOfHour() = 1970-05-01 12:05:31 = 72331424
=== modern java.time methods ===
note that LocalDateTime is current time zone while default Instant is UTC with time zone Z appended
java.time.LocalDateTime.now(), Instant.now() = 2022-01-23T20:02:01.267763900, 2022-01-24T04:02:01.269764Z
java.time.LocalDateTime.now(), Instant.now() = 2022-01-23T20:02:01.270748500, 2022-01-24T04:02:01.270748500Z
java.time.LocalDateTime.now(), Instant.now() = 2022-01-23T20:02:01.271426100, 2022-01-24T04:02:01.271426100Z
sleep for 1000 msec...
java.time.LocalDateTime.now(), Instant.now() = 2022-01-23T20:02:02.277595700, 2022-01-24T04:02:02.277595700Z
java.time.LocalDateTime.now(), Instant.now() = 2022-01-23T20:02:02.277735400, 2022-01-24T04:02:02.277735400Z
java.time.LocalDateTime.now(), Instant.now() = 2022-01-23T20:02:02.277735400, 2022-01-24T04:02:02.277735400Z
DisTime.hasEpochLvc() = false
DisTime.setEpochLvcNow()...
DisTime.hasEpochLvc(), = true
DisTime.getEpochLvc(), Instant.now(), duration = 2022-01-24T04:02:02.279866100Z, 2022-01-24T04:02:02.279866100Z, 0 msec
sleep for 1000 msec...
DisTime.getEpochLvc(), Instant.now(), duration = 2022-01-24T04:02:02.279866100Z, 2022-01-24T04:02:03.289787Z, 1009 msec
*** DisTime.main() self test complete.
BUILD SUCCESSFUL (total time: 0 seconds)
BUILD SUCCESSFUL (total time: 2 seconds)
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