IDs and Addresses on sillysky.net

CIdFactory

Tue, 14 Oct 2025 00:00:00 +0000

We use a factory to create IDs. The reason for this is the possibility to introduce additional ID types. The CIdFactory is therefore also a registry for factories of type IIdFactory.

We have not designed the CIdFactory as a service, because in the code many static IDs are defined.

Create an ID

The simplest method is to create IDs from an integer, from a string or from a UUID:

@NotNull
public static IId fromObject(@Nullable final Object aId);

Beispiele:

CNamespaceAddress

Tue, 14 Oct 2025 00:00:00 +0000

The namespace address is the address of a namespace. It consists of a node address to identify the node and a namespace ID. In string form, the address is structured like this: "nid.nodeId.segmentId".

Constructors

The default constructor creates an invalid address.

final CNamespaceAddress a = new CNamespaceAddress();

There is a constructor that takes a namespace ID and creates a local address. The node address remains empty. Empty or invalid node addresses are considered local addresses.

CNodeAddress

Tue, 14 Oct 2025 00:00:00 +0000

The node address is the rear half of a target address, consisting of NodeId and SegmentId. The node address can be used to identify a node precisely.

Constructors and static factory methods

The default constructor is used to create the local node address, i.e. the address, which belongs to the own node.

final CNodeAddress n = new CNodeAddress();

An invalid or empty node address is created with the constructor, which takes a Boolean. The value does not matter. However, it is better to use the EMPTY public field here.

CNodeId

Tue, 14 Oct 2025 00:00:00 +0000

The NodeId has its own class CNodeId , which is derived from the IId. It is unique in a segment and can be freely assigned.

Empty NodeId

There is a public EMPTY field, which is an invalid NodeId .

Constructors

The default constructor creates an invalid ID.

public CNodeId();

A NodeId can be made from a normal ID.

public CNodeId(@NotNull final IId aId);

Probably the most used is the constructor, which takes a string.

public CNodeId(@NotNull final String aId);

There is a factory method that creates a NodeId from an object.

CSegmentId

Tue, 14 Oct 2025 00:00:00 +0000

A Segment is a group of Nodes with the same ID. The SegmentId has its own class CSegmentId , which is derived from the IId.

Empty SegmentId

There is a public EMPTY field, which is an invalid SegmentId .

Constructors

The default constructor creates an invalid SegmentID .

public CSegmentId();

A SegmentId can be made from a normal ID.

public CSegmentId(@NotNull final IId aId);

Probably the most used is the constructor, which takes a string.

public CSegmentId(@NotNull final String aId);

Another constructor converts a UUID into an ID.

CTargetAddress

Tue, 14 Oct 2025 00:00:00 +0000

The target address is assigned to a target when it has been successfully registered with the target registry. The target address is composed of a target ID (unique for a namespace) and the namespace address.

Constructors

First follows a constructor with the passing of all four components:

public CTargetAddress(@NotNull final IId aTargetID,
                      @NotNull final IId aNamespaceID,
                      @NotNull final CNodeId aNodeId,
                      @NotNull final CSegmentId aSegmentId);

The SegmentId remains empty here. An empty NodeId or SegmentId is equivalent to specifying a local ID.

IIdFactory

Tue, 14 Oct 2025 00:00:00 +0000

The IIdFactory serves as a factory for classes that implement the IId interface. Currently, 4 different IDs are implemented:

the Integer ID for positive integer
the String ID
the UUID ID
the empty ID

You can write your own custom ID classes.

Create an ID

The factory must be able to create an ID from a Java object:

@Nullable IId fromObject(@Nullable Object aObj);

Creation of a random value

The factory should be able to create a random ID:

The Namespace ID (NID)

Tue, 14 Oct 2025 00:00:00 +0000

The namespace ID is of type ID and unique to a namespace within a node.

The CWellKnownNID class

In the CWellKnownNID class, many namespace IDs are defined that are used by supplied plugins.

The Target ID (TID)

Tue, 14 Oct 2025 00:00:00 +0000

Each target (object that can receive messages) receives an ID during registration. The target ID (short: TID) is of type ID and is unique for a target within a namespace. The same TID can exist again in other namespaces. This is used when loading multiple instances of apps.

If no TID is given when registering the target, then a "random" numeric TID is generated. This is the normal case.

If a TID is given, it will be used if no target with this ID has been registered in this namespace yet.