X-Git-Url: https://gerrit.simantics.org/r/gitweb?p=simantics%2Fplatform.git;a=blobdiff_plain;f=bundles%2Forg.simantics.db.layer0%2Fsrc%2Forg%2Fsimantics%2Fdb%2Flayer0%2Futil%2FLayer0Utils.java;h=c04ca3cd1e0b758d1d66a8a8628887dab576f5cc;hp=beec63aa1b5a3f928111097b08284f497ba96b43;hb=f2f1f3fe7b467654a0afa4e586ebcd06a54ebfea;hpb=3a10ce856f7124f83cf03d6e7f7576da237a7cbb

diff --git a/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/util/Layer0Utils.java b/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/util/Layer0Utils.java
index beec63aa1..c04ca3cd1 100644
--- a/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/util/Layer0Utils.java
+++ b/bundles/org.simantics.db.layer0/src/org/simantics/db/layer0/util/Layer0Utils.java
@@ -1394,10 +1394,40 @@ public class Layer0Utils {
      * @param graph
      * @param component
      *            for which the identifier is added
+     * @param add
+     *            <code>true</code> to invoke addLiteral, <code>false</code> to
+     *            invoke claimLiteral
      * @throws DatabaseException
      */
-    public static void addL0Identifier(WriteGraph graph, Resource component) throws DatabaseException {
+    public static void claimNewIdentifier(WriteGraph graph, Resource component, boolean add) throws DatabaseException {
         Layer0 L0 = Layer0.getInstance(graph);
-        graph.addLiteral(component, L0.identifier, L0.identifier_Inverse, L0.GUID, GUID.random(), GUID.BINDING);
+        GUID guid = GUID.random();
+        if (add)
+            graph.addLiteral(component, L0.identifier, L0.identifier_Inverse, L0.GUID, guid, GUID.BINDING);
+        else
+            graph.claimLiteral(component, L0.identifier, L0.identifier_Inverse, L0.GUID, guid, GUID.BINDING);
+    }
+
+    /**
+     * Sets a new random unique identifier for the specified entity if it already
+     * has an identifier. If the entity does not have a previous identifier, nothing
+     * is done.
+     * 
+     * @param graph
+     * @param entity
+     *            for which the identifier is added
+     * @return <code>true</code> if the identifier was renewed, <code>false</code>
+     *         otherwise
+     * @throws DatabaseException
+     * @see {@link #claimNewIdentifier(WriteGraph, Resource, boolean)}
+     */
+    public static boolean renewIdentifier(WriteGraph graph, Resource entity) throws DatabaseException {
+        Layer0 L0 = Layer0.getInstance(graph);
+        Statement stm = graph.getPossibleStatement(entity, L0.identifier);
+        if (stm != null) {
+            graph.claimValue(stm.getObject(), GUID.random(), GUID.BINDING);
+            return true;
+        }
+        return false;
     }
 }