bundles/org.simantics.db.indexing/src/org/simantics/db/indexing/QueryIndexResources.java

   1 package org.simantics.db.indexing;
   2
   3 import java.util.Collections;
   4 import java.util.List;
   5
   6 import org.simantics.db.ReadGraph;
   7 import org.simantics.db.Resource;
   8 import org.simantics.db.common.primitiverequest.Adapter;
   9 import org.simantics.db.common.procedure.adapter.TransientCacheListener;
  10 import org.simantics.db.common.request.BinaryRead;
  11 import org.simantics.db.exception.DatabaseException;
  12 import org.simantics.operation.Layer0X;
  13 import org.simantics.scl.runtime.function.Function;
  14
  15 /**
  16  * A (cacheable) query to optimize single index queries for immutable
  17  * indexes such as ontologies.
  18  */
  19 class QueryIndexResources extends BinaryRead<Resource, String, List<Resource>> {
  20
  21         public QueryIndexResources(Resource index, String filter) {
  22                 super(index, filter);
  23         }
  24
  25         @Override
  26         public List<Resource> perform(ReadGraph graph) throws DatabaseException {
  27
  28                 Layer0X L0X = Layer0X.getInstance(graph);
  29
  30                 @SuppressWarnings({ "unchecked", "rawtypes" })
  31                 Function dependencies = graph.syncRequest(new Adapter(L0X.DependencyResources, Function.class), TransientCacheListener.<Function>instance());
  32
  33                 @SuppressWarnings("unchecked")
  34                 List<Resource> results = (List<Resource>)dependencies.apply(graph, parameter, parameter2);
  35                 if (results == null || results.isEmpty())
  36                         return Collections.emptyList();
  37
  38                 return results;
  39
  40         }
  41
  42 }