Introduce typed UUIDs.

[lgpl/argeo-commons.git] / org.argeo.api.uuid / src / org / argeo / api / uuid / TypedUuid.java

diff --git a/org.argeo.api.uuid/src/org/argeo/api/uuid/TypedUuid.java b/org.argeo.api.uuid/src/org/argeo/api/uuid/TypedUuid.java
new file mode 100644 (file)
index 0000000..55a67ab
--- /dev/null
+++ b/org.argeo.api.uuid/src/org/argeo/api/uuid/TypedUuid.java
@@ -0,0 +1,60 @@
+package org.argeo.api.uuid;
+
+import java.util.Objects;
+import java.util.UUID;
+
+/**
+ * Base class for objects which are explicitly typed, based on the various UUID
+ * versions. Such a derivation hierarchy still represents the {@link UUID}
+ * itself, not the objects, data or concept that it identifies. Just like
+ * {@link UUID}s, {@link TypedUuid} should be used as identifier, not as base
+ * class for complex objects. It should rather be seen as a framework to build
+ * richer IDs, which are strictly compliant with the UUID specifications.
+ */
+public abstract class TypedUuid extends UuidHolder {
+       private static final long serialVersionUID = APM.SERIAL;
+
+       /** Default constructor. */
+       public TypedUuid(UUID uuid) {
+               super(uuid);
+       }
+
+       /**
+        * Whether this {@link UUID} has no meaning in itself (RFC4122 v3, v4 and v5,
+        * and Microsoft GUID). Only RFC4122 v1 and v2 can be interpreted.
+        */
+       public boolean isOpaque() {
+               if (uuid.variant() == 2) {// RFC4122
+                       return uuid.version() == 4 || uuid.version() == 5 || uuid.version() == 3;
+               } else if (uuid.variant() == 6) {// Microsoft
+                       return true;
+               } else {
+                       return true;
+               }
+       }
+
+       /**
+        * Constructs a {@link TypedUuid} of the most appropriate subtype, based on this
+        * {@link UUID}.
+        */
+       public static TypedUuid of(UUID uuid) {
+               Objects.requireNonNull(uuid, "UUID cannot be null");
+               if (uuid.variant() == 2) {// RFC 4122
+                       switch (uuid.version()) {
+                       case 1:
+                               return new TimeUuid(uuid);
+                       case 4:
+                               return new RandomUuid(uuid);
+                       case 3:
+                       case 5:
+                               return new UnkownNameUuid(uuid);
+                       default:
+                               throw new IllegalArgumentException("UUIDs with version " + uuid.version() + " are not supported.");
+                       }
+               } else if (uuid.variant() == 6) {// Microsoft
+                       throw new IllegalArgumentException("Microsoft UUIDs (aka. GUIDs) are not supported.");
+               } else {
+                       throw new IllegalArgumentException("UUIDs with variant " + uuid.variant() + " are not supported.");
+               }
+       }
+}