DateTime

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id: py-DateTime

DateTime

Represents a point in time with date, time, and timezone offset information. Use DateTime when you need to work with timestamps, compare moments, or format dates for output.

DateTime instances are immutable — all modification methods return new instances.

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At a Glance

# Current time
now = DateTime.now()

# Specific moment
meeting = DateTime.of(2024, 12, 25, 14, 30)

# From a string
parsed = DateTime.parse('2024-12-25 14:30:00', 'uuuu-MM-dd HH:mm:ss')

# Format for output
stream.log_info(meeting.toString('EEEE, MMM dd uuuu'))  # "Wednesday, Dec 25 2024"

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Properties

Property	Type	Description
year	int	Year (e.g., 2024)
month	int	Month of year, 1–12
dayOfMonth	int	Day of month, 1–31
dayOfWeek	int	Day of week, 1 (Monday) – 7 (Sunday)
dayOfYear	int	Day of year, 1–366
hour	int	Hour of day, 0–23
minute	int	Minute of hour, 0–59
second	int	Second of minute, 0–59
nano	int	Nanosecond of second, 0–999,999,999
date	LocalDate	Date component only
time	Time	Time component only

dt = DateTime.of(2024, 3, 15, 10, 30, 45)

stream.log_info(f"{dt.year}-{dt.month}-{dt.dayOfMonth}")        # "2024-3-15"
stream.log_info(f"{dt.hour}:{dt.minute}:{dt.second}")           # "10:30:45"
stream.log_info(f"Day {dt.dayOfYear} of the year")              # "Day 75 of the year"
stream.log_info(f"Day of week: {dt.dayOfWeek}")                 # 5 (Friday)

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Creating DateTime

now(zone?)

Returns the current date and time.

Parameter	Type	Description
zone (optional)	TimeZone	Timezone; defaults to system timezone

now = DateTime.now()
ny_now = DateTime.now(TimeZone.of('America/New_York'))

of(year, month?, day?, hour?, minute?, second?, nano?, zone?)

Creates a DateTime from individual components.

# Minimal: just year
y2k = DateTime.of(2000)

# Date only
birthday = DateTime.of(1990, 5, 15)

# Full datetime
precise = DateTime.of(2024, 12, 25, 14, 30, 0, 0)

# With timezone offset
india_time = DateTime.of(2024, 12, 25, 14, 30, 0, 0, ZoneOffset.of(5, 30))

parse(value, format?)

Parses a string into a DateTime.

# ISO format (default)
dt1 = DateTime.parse('2024-12-25T14:30:00')

# Custom format
dt2 = DateTime.parse('25/12/2024 14:30', 'dd/MM/uuuu HH:mm')

Format Patterns

See Java DateTimeFormatter for full pattern syntax. Common patterns:

• uuuu — year (2024)
• MM — month (03)
• dd — day (15)
• HH — hour 24h (14)
• mm — minute (30)
• ss — second (45)

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Comparing DateTimes

Method	Returns	Description
isAfter(other)	bool	This moment is later than other
isBefore(other)	bool	This moment is earlier than other
isEqual(other)	bool	Same moment in time

start = DateTime.parse('2024-01-01T00:00:00')
end = DateTime.parse('2024-12-31T23:59:59')

if end.isAfter(start):
    stream.log_info('End is after start')

# Check if within business hours
now = DateTime.now()
if now.hour >= 9 and now.hour < 17:
    stream.log_info('Within business hours')

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Adding Time

All plusX() methods return a new DateTime. The original is unchanged.

Method	Description
plusYears(years)	Add years
plusMonths(months)	Add months
plusDays(days)	Add days
plusHours(hours)	Add hours
plusMinutes(minutes)	Add minutes
plusSeconds(seconds)	Add seconds
plusNanos(nanos)	Add nanoseconds

now = DateTime.now()

tomorrow = now.plusDays(1)
next_week = now.plusDays(7)
next_hour = now.plusHours(1)

# Calculate expiry (30 days from now)
expiry = now.plusDays(30)
message.setDateTime(dataDictionary.type.Order.EXPIRY_DATE, expiry)

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Subtracting Time

Method	Description
minusYears(years)	Subtract years
minusMonths(months)	Subtract months
minusDays(days)	Subtract days
minusHours(hours)	Subtract hours
minusMinutes(minutes)	Subtract minutes
minusSeconds(seconds)	Subtract seconds
minusNanos(nanos)	Subtract nanoseconds

now = DateTime.now()
yesterday = now.minusDays(1)
last_month = now.minusMonths(1)

# Check if record is older than 90 days
created = message.getDateTime(dataDictionary.type.Record.CREATED_AT)
if created.plusDays(90).isBefore(now):
    message.addStatus(Severity.WARNING, Status.create(VENDOR, 'STALE_RECORD'))

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Changing Components

Set individual components without affecting others.

Method	Description
withYear(year)	Set year
withMonth(month)	Set month (1–12)
withDayOfMonth(day)	Set day of month (1–31)
withHour(hour)	Set hour (0–23)
withMinute(minute)	Set minute (0–59)
withSecond(second)	Set second (0–59)
withNano(nano)	Set nanosecond

dt = DateTime.of(2024, 3, 15, 10, 30)

# Same date, different time
noon = dt.withHour(12).withMinute(0)

# Same time, first of month
first_of_month = dt.withDayOfMonth(1)

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Timezone Conversion

atZone(zone)

Returns the same moment in a different timezone.

utc = DateTime.now(TimeZone.UTC)
berlin = utc.atZone(TimeZone.of('Europe/Berlin'))
tokyo = utc.atZone(TimeZone.of('Asia/Tokyo'))

stream.log_info(f"UTC: {utc.toString()}")
stream.log_info(f"Berlin: {berlin.toString()}")
stream.log_info(f"Tokyo: {tokyo.toString()}")

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Converting to Numbers

Method	Returns	Description
toEpochSecond()	int	Seconds since Unix epoch (1970-01-01T00:00:00Z)
toEpochMilli()	int	Milliseconds since Unix epoch

now = DateTime.now()
epoch_seconds = now.toEpochSecond()   # 1700000000
epoch_millis = now.toEpochMilli()     # 1700000000000

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Formatting

toString(format?)

Converts to a formatted string.

dt = DateTime.of(2024, 12, 25, 14, 30, 0)

# Default ISO format
dt.toString()                          # "2024-12-25T14:30:00"

# Custom formats
dt.toString('uuuu-MM-dd')              # "2024-12-25"
dt.toString('dd/MM/uuuu HH:mm')        # "25/12/2024 14:30"
dt.toString('EEEE, MMMM dd uuuu')      # "Wednesday, December 25 2024"

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Complete Example

def on_message():
    order_date = message.getDateTime(dataDictionary.type.Order.ORDER_DATE)
    now = DateTime.now()

    # Check if order is recent (within 7 days)
    if order_date.plusDays(7).isAfter(now):
        stream.log_info('Recent order')

    # Set expected delivery (5 business days later — simplified)
    delivery_date = order_date.plusDays(5)
    message.setDateTime(dataDictionary.type.Order.EXPECTED_DELIVERY, delivery_date)

    # Format for customer notification
    formatted = delivery_date.toString('EEEE, MMMM dd uuuu')
    message.setString(dataDictionary.type.Order.DELIVERY_TEXT, formatted)

    stream.emit(message, OUTPUT_PORT)

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See Also

• LocalDate — Date without time
• Time — Time without date
• TimeZone — Timezone definitions
• ZoneOffset — UTC offset