Improve time based UUID speed and configuration.

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

diff --git a/org.argeo.api.uuid/src/org/argeo/api/uuid/NodeIdSupplier.java b/org.argeo.api.uuid/src/org/argeo/api/uuid/NodeIdSupplier.java
new file mode 100644 (file)
index 0000000..ae9686c
--- /dev/null
+++ b/org.argeo.api.uuid/src/org/argeo/api/uuid/NodeIdSupplier.java
@@ -0,0 +1,20 @@
+package org.argeo.api.uuid;
+
+import java.util.function.Supplier;
+
+/** A factory for node id base */
+public interface NodeIdSupplier extends Supplier<Long> {
+       long LEAST_SIG_RFC4122_VARIANT = (1l << 63);
+
+       static long toNodeIdBase(byte[] node) {
+               assert node.length == 6;
+               return LEAST_SIG_RFC4122_VARIANT // base for Leach–Salz UUID
+                               | (node[0] & 0xFFL) //
+                               | ((node[1] & 0xFFL) << 8) //
+                               | ((node[2] & 0xFFL) << 16) //
+                               | ((node[3] & 0xFFL) << 24) //
+                               | ((node[4] & 0xFFL) << 32) //
+                               | ((node[5] & 0xFFL) << 40); //
+       }
+
+}