Skip to content

Instantly share code, notes, and snippets.

Embed
What would you like to do?
Extension methods for Jackson Json for typesafe Json handling in Kotlin
import com.fasterxml.jackson.databind.JsonNode
object JsonExtensions {
fun JsonNode.objectAt(key: String): JsonNode? = this.takeIf { it.isObject }?.get(key)?.takeIf { it.isObject }
fun JsonNode.arrayAt(key: String): JsonNode? = this.takeIf { it.isObject }?.get(key)?.takeIf { it.isArray }
fun JsonNode.booleanAt(key: String): Boolean? = this.takeIf { it.isObject && it.has(key) }?.get(key)?.takeIf { it.isBoolean }?.asBoolean()
fun JsonNode.intAt(key: String): Int? = this.takeIf { it.isObject && it.has(key) }?.get(key)?.takeIf { it.isIntegralNumber }?.asInt()
fun JsonNode.longAt(key: String): Long? = this.takeIf { it.isObject && it.has(key) }?.get(key)?.takeIf { it.isIntegralNumber }?.asLong()
fun JsonNode.doubleAt(key: String): Double? = this.takeIf { it.isObject && it.has(key) }?.get(key)?.takeIf { it.isFloatingPointNumber }?.asDouble()
fun JsonNode.stringAt(key: String): String? = this.takeIf { it.isObject && it.has(key) }?.get(key)?.takeIf { it.isTextual }?.asText()
fun JsonNode.objectAt(index: Int): JsonNode? = this.takeIf { it.isArray }?.get(index)?.takeIf { it.isObject }
fun JsonNode.arrayAt(index: Int): JsonNode? = this.takeIf { it.isArray }?.get(index)?.takeIf { it.isArray }
fun JsonNode.booleanAt(index: Int): Boolean? = this.takeIf { it.isArray && index < it.size() }?.get(index)?.takeIf { it.isBoolean }?.asBoolean()
fun JsonNode.intAt(index: Int): Int? = this.takeIf { it.isArray && index < it.size() }?.get(index)?.takeIf { it.isIntegralNumber }?.asInt()
fun JsonNode.longAt(index: Int): Long? = this.takeIf { it.isArray && index < it.size() }?.get(index)?.takeIf { it.isIntegralNumber }?.asLong()
fun JsonNode.doubleAt(index: Int): Double? = this.takeIf { it.isArray && index < it.size() }?.get(index)?.takeIf { it.isFloatingPointNumber }?.asDouble()
fun JsonNode.stringAt(index: Int): String? = this.takeIf { it.isArray && index < it.size() }?.get(index)?.takeIf { it.isTextual }?.asText()
fun JsonNode.values(): List<JsonNode>? = this.takeIf { it.isArray }?.elements()?.asSequence()?.toList()
}
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment