--- /dev/null
+package org.simantics.db.layer0.genericrelation;\r
+\r
+import org.simantics.db.ReadGraph;\r
+import org.simantics.db.Resource;\r
+import org.simantics.db.Session;\r
+import org.simantics.db.common.request.ParametrizedPrimitiveRead;\r
+import org.simantics.db.layer0.adapter.GenericRelationIndex;\r
+import org.simantics.db.procedure.Listener;\r
+import org.simantics.utils.datastructures.Pair;\r
+\r
+class ExternalRequest extends ParametrizedPrimitiveRead<Pair<GenericRelationIndex,Resource>,Long> implements Runnable {\r
+\r
+ private static long value = 0;\r
+ private Session session;\r
+ private Listener<Long> procedure;\r
+\r
+ public ExternalRequest(GenericRelationIndex index, Resource model) {\r
+ super(Pair.make(index, model));\r
+ }\r
+\r
+ @Override\r
+ public void register(ReadGraph graph, Listener<Long> procedure) {\r
+ synchronized(getClass()) {\r
+ procedure.execute(value++);\r
+ }\r
+ if(procedure.isDisposed()) return;\r
+ assert(this.procedure == null);\r
+ this.session = graph.getSession();\r
+ this.procedure = procedure;\r
+ parameter.first.addListener(graph, parameter.second, this);\r
+ }\r
+ \r
+ @Override\r
+ public void unregistered() {\r
+ parameter.first.removeListener(session, parameter.second, this);\r
+ }\r
+ \r
+ @Override\r
+ public void run() {\r
+ synchronized(getClass()) {\r
+ procedure.execute(value++);\r
+ }\r
+ }\r
+ \r
+}
\ No newline at end of file