Extension methods for Jackson Json for typesafe Json handling in Kotlin

JacksonExtensions.kt

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()
}