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=3da57809ae0f381debf8e6520c017855b2ad7144;hb=f2f1f3fe7b467654a0afa4e586ebcd06a54ebfea;hpb=61033f112b0a2e643bf8530b99bcf90c64464f30

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 3da57809a..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
@@ -1407,4 +1407,27 @@ public class Layer0Utils {
         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;
+    }
 }