Instant truncatedTo() method in Java with Examples

The truncatedTo() method of an Instant class is used to get the value of this Instant in the specified unit. This method takes a parameter Unit, which is the Unit in which this Instant is to be truncated to. It returns a truncated immutable Instant with the value in the specified unit. Syntax:

public Instant truncatedTo(TemporalUnit unit)

Parameter: This method takes a parameter unit which is the unit in which this Instant is to be truncated to. It should not be null. Returns: This method returns an immutable truncated Instant with the value in the specified unit. Exception: This method throws following Exceptions:

DateTimeException: if the unit is invalid for truncation.
UnsupportedTemporalTypeException: if the unit is not supported.

Below programs illustrate the Instant.truncatedTo() method: Program 1:

Java

// Java program to demonstrate
// Instant.truncatedTo() method

import java.time.*;
import java.time.temporal.ChronoUnit;

public class GFG {
    public static void main(String[] args)
    {

        // create a Instant object
        Instant instant
            = Instant.parse("2018-12-30T09:24:54.63Z");

        // print instance
        System.out.println("Instant before"
                           + " truncate: "
                           + instant);

        // truncate to ChronoUnit.HOURS
        // means unit smaller than Hour
        // will be Zero
        Instant returnvalue
            = instant.truncatedTo(ChronoUnit.HOURS);

        // print result
        System.out.println("Instant after "
                           + " truncate: "
                           + returnvalue);
    }
}

Output:

Instant before truncate: 2018-12-30T09:24:54.630Z
Instant after  truncate: 2018-12-30T09:00:00Z

Program 2:

Java

// Java program to demonstrate
// Instant.truncatedTo() method

import java.time.*;
import java.time.temporal.ChronoUnit;

public class GFG {
    public static void main(String[] args)
    {

        // create a Instant object
        Instant instant
            = Instant.parse("2018-12-30T09:24:54.63Z");

        // print instance
        System.out.println("Instant before"
                           + " truncate: "
                           + instant);

        // truncate to ChronoUnit.DAYS
        // means unit smaller than DAY
        // will be Zero
        Instant returnvalue
            = instant.truncatedTo(ChronoUnit.DAYS);

        // print result
        System.out.println("Instant after "
                           + " truncate: "
                           + returnvalue);
    }
}

Output:

Instant before truncate: 2018-12-30T09:24:54.630Z
Instant after  truncate: 2018-12-30T00:00:00Z

Program 3: To show Exception:

Java

// Java program to demonstrate
// Instant.truncatedTo() method

import java.time.*;
import java.time.temporal.ChronoUnit;

public class GFG {
    public static void main(String[] args)
    {

        // create a Instant object
        Instant instant
            = Instant.parse("2018-12-30T09:24:54.63Z");

        try {
            instant.truncatedTo(ChronoUnit.ERAS);
        }
        catch (Exception e) {

            // print result
            System.out.println("Exception: " + e);
        }
    }
}

Output:

Exception:
 java.time.temporal.UnsupportedTemporalTypeException:
 Unit is too large to be used for truncation

Reference: https://docs.oracle.com/javase/10/docs/api/java/time/Instant.html#truncatedTo(java.time.temporal.TemporalUnit)

Instant truncatedTo() method in Java with Examples

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