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# Time Types
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Cross-platform time and duration types that map to Google Well-Known Types (google.protobuf.Duration and google.protobuf.Timestamp). These provide consistent time handling across all Kotlin multiplatform targets.
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## Capabilities
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### Duration
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Represents a time duration with nanosecond precision, mapping to google.protobuf.Duration.
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```kotlin { .api }
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/**
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 * A measurement of time. Durations may be positive, zero, or negative.
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 * Maps to google.protobuf.Duration
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 */
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expect class Duration {
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    /** Get seconds component */
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    fun getSeconds(): Long
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    /** Get nanoseconds component (0-999,999,999) */
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    fun getNano(): Int
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}
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/** Create duration from seconds and nanoseconds */
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expect fun durationOfSeconds(seconds: Long, nano: Long): Duration
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```
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### Instant
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Represents a timestamp with nanosecond precision, mapping to google.protobuf.Timestamp.
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```kotlin { .api }
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/**
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 * Represents a timestamp (google.protobuf.Timestamp)
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 */
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expect class Instant {
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    /** Seconds since Unix epoch (1970-01-01T00:00:00Z) */
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    fun getEpochSecond(): Long
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    /** Nanoseconds component (0-999,999,999) */
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    fun getNano(): Int
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}
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/** Create instant from epoch seconds and nanoseconds */
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expect fun ofEpochSecond(epochSecond: Long, nano: Long): Instant
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```
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**Usage Examples:**
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```kotlin
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import com.squareup.wire.*
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// Create duration (5.5 seconds)
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val duration = durationOfSeconds(5, 500_000_000)
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println("Seconds: ${duration.getSeconds()}") // 5
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println("Nanos: ${duration.getNano()}")     // 500000000
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// Create instant (Unix timestamp)
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val instant = ofEpochSecond(1640995200, 123_456_789) // 2022-01-01T00:00:00.123456789Z
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println("Epoch seconds: ${instant.getEpochSecond()}") // 1640995200
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println("Nanos: ${instant.getNano()}")               // 123456789
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// Use with ProtoAdapter
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val encodedDuration = ProtoAdapter.DURATION.encode(duration)
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val decodedDuration = ProtoAdapter.DURATION.decode(encodedDuration)
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val encodedInstant = ProtoAdapter.INSTANT.encode(instant)
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val decodedInstant = ProtoAdapter.INSTANT.decode(encodedInstant)
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```