encode

[swuecho]

You can create a custom encoder for handling java.util.Date instances in Circe by utilizing the Encoder type class from the Circe library. Here's an example:

import io.circe._
import java.text.SimpleDateFormat
import java.util.Date

object DateEncoders {
  implicit val encodeDate: Encoder[Date] = new Encoder[Date] {
    val sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ")

    override def apply(a: Date): Json = Json.fromString(sdf.format(a))
  }
}

In this example, we create a custom encoder for java.util.Date instances by implicitly defining an Encoder[Date]. Inside the Encoder instance, we define a SimpleDateFormat to format the date and then use it to convert the Date instance to a String representation, which is then wrapped in a Json object using Json.fromString.

To use this custom encoder, you can import it alongside the rest of your Circe code and Circe will use it automatically when encountering Date instances during encoding.

[swuecho]

In Scala 3, you can create a custom given instance for encoding java.time.LocalDateTime instances using Circe. Here's an example:

import io.circe._
import java.time.LocalDateTime
import java.time.format.DateTimeFormatter

object LocalDateTimeEncoders {
  given Encoder[LocalDateTime] with {
    val formatter: DateTimeFormatter = DateTimeFormatter.ISO_LOCAL_DATE_TIME

    override def apply(a: LocalDateTime): Json = Json.fromString(formatter.format(a))
  }
}

In this example, we define a given instance of Encoder for java.time.LocalDateTime. Inside the given block, we define a DateTimeFormatter to format the LocalDateTime and then use it to convert the LocalDateTime instance to a String representation, which is then wrapped in a Json object using Json.fromString.

To use this custom encoder, you can import it alongside the rest of your Circe code and Circe will use it automatically when encountering LocalDateTime instances during encoding.