getValue<T> method

T getValue<T>(CborObject key)

Retrieves the value associated with the specified key from the CborMapValue.

If key does not exist in the map and T is nullable, returns null. Otherwise, throws a MessageException.

Implementation

T getValue<T>(CborObject key) {
  if (!value.containsKey(key)) {
    if (null is T) return null as T;
    throw MessageException("Key does not exist.", details: {
      "Key": "${key.runtimeType}",
      "Keys": value.keys.map((e) => e.runtimeType).join(", ")
    });
  }
  final val = value[key];
  if (null is T && val is CborNullValue) return null as T;
  if (val is CborObject && val.value is T) return val.value;
  if (val is! T) {
    throw MessageException("Failed to cast value.",
        details: {"Excepted": "${val.runtimeType}", "Type": "$T"});
  }
  return val;
}