MpLocalTime

A time of day — no date, no timezone. The right type for business hours, alarm times, and recurring schedule patterns.

When to use MpLocalTime

• Business hours ("open 9:00 to 17:00")
• Alarm or reminder times
• Time-of-day patterns in scheduling
• Time slots and availability windows (see MpLocalTimeSlot)

Creating

import io.peekandpoke.ultra.datetime.MpLocalTime

val time = MpLocalTime.of(14, 30, 15)             // 14:30:15
val withMillis = MpLocalTime.of(14, 30, 15, 500)  // 14:30:15.500
val parsed = MpLocalTime.parse("14:30:15")
val maybe = MpLocalTime.tryParse("not-a-time")    // null

// From raw units
val fromMillis = MpLocalTime.ofMilliSeconds(52_215_000L)  // 14:30:15
val fromSeconds = MpLocalTime.ofSecondOfDay(52_215L)       // 14:30:15

// Constants
val midnight = MpLocalTime.Min   // 00:00:00.000
val endOfDay = MpLocalTime.Max   // 23:59:59.999
val noon = MpLocalTime.Noon      // 12:00:00.000

Properties

val time = MpLocalTime.of(14, 30, 15, 500)

time.hour          // 14
time.minute        // 30
time.second        // 15
time.milliSecond   // 500

What MpLocalTime can do

MpLocalTime is deliberately small. A time of day without a date can only support a few operations safely:

import kotlin.time.Duration.Companion.hours
import kotlin.time.Duration.Companion.minutes

val time = MpLocalTime.of(14, 30)

// Add and subtract Duration — wraps around midnight
val later = time.plus(2.hours)       // 16:30
val earlier = time.minus(30.minutes) // 14:00
val wrapped = time.plus(12.hours)    // 02:30 (next day, wraps)

// Duration between two times
val other = MpLocalTime.of(17, 0)
val diff = other - time  // 2h 30m

// Convert to raw milliseconds of day
time.inWholeMilliSeconds()  // 52200000

What MpLocalTime does not have

A time of day has no calendar context, so these operations are not available:

• No date components (.year, .month, .day)
• No calendar arithmetic (plusDays, plusMonths)
• No conversion to instant or zoned datetime (where would it go without a date?)
• No timezone offset information

To combine a time with a date, use MpLocalDate.atTime():

val date = MpLocalDate.of(2025, 3, 15)
val time = MpLocalTime.of(14, 30)

// Combine into a LocalDateTime
val dt = date.atTime(time)  // 2025-03-15T14:30

// Or directly into a ZonedDateTime
val zoned = date.atTime(time, MpTimezone.of("Europe/Berlin"))

Formatting

val time = MpLocalTime.of(14, 30, 15)

time.toIsoString()     // "14:30:15.000"
time.formatHhMm()      // "14:30"
time.formatHhMmSs()    // "14:30:15"
time.format("HH:mm")   // "14:30"

Time constants

JVM interop

// MpLocalTime -> java.time.LocalTime
val javaTime: java.time.LocalTime = mpTime.jvm

// java.time.LocalTime -> MpLocalTime
val mpTime: MpLocalTime = javaTime.mp