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CARP Documentation

DataType

Identifies a type of data by namespace and name.

Defines a type of data which can be processed by the platform (e.g., measured / collected / uploaded). This is used by the infrastructure to determine whether the requested data can be collected on a device, how to upload it, how to process it in a secondary data stream, or how triggers can act on it.

Its string form <namespace>.<name> (e.g., dk.cachet.carp.geolocation) is what Measure.type holds; see Measure.dataType and Data.dataType.

Annotations

Constructors

DataType.fromJson

DataType.fromJson(
  1. Map<String, dynamic> json
)

DataType.fromString

DataType.fromString(
  1. String type
)

Parses a fully qualified type like dk.cachet.carp.geolocation.

The part after the last '.' is the name; the rest is the namespace.

DataType

const DataType(
  1. String namespace,
  2. String name
)

Create a DataType.

Properties

hashCode

int get hashCode
override

The hash code for this object.

A hash code is a single integer which represents the state of the object that affects operator == comparisons.

All objects have hash codes. The default hash code implemented by Object represents only the identity of the object, the same way as the default operator == implementation only considers objects equal if they are identical (see identityHashCode).

If operator == is overridden to use the object state instead, the hash code must also be changed to represent that state, otherwise the object cannot be used in hash based data structures like the default Set and Map implementations.

Hash codes must be the same for objects that are equal to each other according to operator ==. The hash code of an object should only change if the object changes in a way that affects equality. There are no further requirements for the hash codes. They need not be consistent between executions of the same program and there are no distribution guarantees.

Objects that are not equal are allowed to have the same hash code. It is even technically allowed that all instances have the same hash code, but if clashes happen too often, it may reduce the efficiency of hash-based data structures like HashSet or HashMap.

If a subclass overrides hashCode, it should override the operator == operator as well to maintain consistency.

name

String name
final

The name of this data format.

Uniquely identifies something within the namespace. The name may not contain any periods. Periods are reserved for namespaces.

namespace

String namespace
final

The data type namespace. See NameSpace.

Uniquely identifies the organization/person who determines how to interpret name. To prevent conflicts, a reverse domain namespace is suggested: e.g., "org.openmhealth" or "dk.cachet.carp".

Methods

toJson

Map<String, dynamic> toJson()

toString

String toString()
override

A string representation of this object.

Some classes have a default textual representation, often paired with a static parse function (like int.parse). These classes will provide the textual representation as their string representation.

Other classes have no meaningful textual representation that a program will care about. Such classes will typically override toString to provide useful information when inspecting the object, mainly for debugging or logging.

Operators

operator ==

bool operator ==(
  1. Object other
)
override

The equality operator.

The default behavior for all Objects is to return true if and only if this object and other are the same object.

Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:

  • Total: It must return a boolean for all arguments. It should never throw.

  • Reflexive: For all objects o, o == o must be true.

  • Symmetric: For all objects o1 and o2, o1 == o2 and o2 == o1 must either both be true, or both be false.

  • Transitive: For all objects o1, o2, and o3, if o1 == o2 and o2 == o3 are true, then o1 == o3 must be true.

The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.

If a subclass overrides the equality operator, it should override the hashCode method as well to maintain consistency.