--- /dev/null
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ * VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.db.common.utils;\r
+\r
+import java.util.ArrayList;\r
+import java.util.Collection;\r
+import java.util.Collections;\r
+import java.util.HashSet;\r
+import java.util.List;\r
+import java.util.ListIterator;\r
+import java.util.Set;\r
+\r
+import org.simantics.databoard.Bindings;\r
+import org.simantics.db.AsyncReadGraph;\r
+import org.simantics.db.ReadGraph;\r
+import org.simantics.db.Resource;\r
+import org.simantics.db.WriteGraph;\r
+import org.simantics.db.WriteOnlyGraph;\r
+import org.simantics.db.common.request.ReadRequest;\r
+import org.simantics.db.exception.DatabaseException;\r
+import org.simantics.db.exception.RuntimeDatabaseException;\r
+import org.simantics.db.exception.ValidationException;\r
+import org.simantics.db.function.DbFunction;\r
+import org.simantics.db.procedure.AsyncMultiProcedure;\r
+import org.simantics.layer0.Layer0;\r
+import org.simantics.utils.datastructures.Pair;\r
+\r
+public class OrderedSetUtils {\r
+\r
+ /**\r
+ * Returns true, if <tt>l</tt> contains the element <tt>el</tt>.\r
+ */\r
+ public static boolean contains(ReadGraph g, Resource l, Resource el) throws DatabaseException {\r
+ return g.hasStatement(el, l) && !l.equals(el);\r
+ }\r
+\r
+ /**\r
+ * Returns the next element in the ordered set or <tt>l</tt>,\r
+ * if <tt>el</tt> is the last element. Called for <tt>el</tt>, returns\r
+ * the first element in the set.\r
+ */\r
+ public static Resource next(ReadGraph g, Resource l, Resource el) throws DatabaseException {\r
+ Collection<Resource> nexts = g.getObjects(el, l);\r
+ if(nexts.size() != 1)\r
+ throw new InvalidOrderedSetException("Invalid list element: " + l + " " + el + " " + nexts.size() + " successors.");\r
+ for(Resource r : nexts)\r
+ return r;\r
+ return null;\r
+ }\r
+\r
+ public static void forNext(AsyncReadGraph g, final Resource l, Resource el, final AsyncMultiProcedure<Resource> procedure) {\r
+ g.forEachObject(el, l, new AsyncMultiProcedure<Resource>() {\r
+\r
+ @Override\r
+ public void exception(AsyncReadGraph graph, Throwable t) {\r
+ procedure.exception(graph, t);\r
+ }\r
+\r
+ @Override\r
+ public void finished(AsyncReadGraph graph) {\r
+ }\r
+\r
+ @Override\r
+ public void execute(AsyncReadGraph graph, Resource nel) {\r
+ if(!nel.equals(l)) {\r
+ procedure.execute(graph, nel);\r
+ forNext(graph, l, nel, procedure);\r
+ }\r
+ }\r
+ });\r
+// Collection<Resource> nexts = g.getObjects(el, l);\r
+// if(nexts.size() != 1)\r
+// throw new NoSingleResultException("Invalid list element: " + nexts.size() + " successors.");\r
+// for(Resource r : nexts)\r
+// return r;\r
+// return null;\r
+ }\r
+\r
+ /**\r
+ * Returns the previouse element in the ordered set or <tt>l</tt>,\r
+ * if <tt>el</tt> is the first element. Called for <tt>el</tt>, returns\r
+ * the last element in the set.\r
+ */\r
+ public static Resource prev(ReadGraph g, Resource l, Resource el) throws DatabaseException {\r
+ Collection<Resource> prevs = g.getObjects(el, g.getInverse(l));\r
+ if(prevs.size() != 1) {\r
+ throw new InvalidOrderedSetException("Invalid list element, " + prevs.size() + " predecessors.");\r
+ }\r
+ for(Resource r : prevs)\r
+ return r;\r
+ return null;\r
+ }\r
+\r
+ /**\r
+ * Adds a given elements <tt>el</tt> to the list <tt>l</tt>. Returns\r
+ * true, if the element was really added.\r
+ */\r
+ public static boolean add(WriteGraph g, Resource l, Resource el) throws DatabaseException {\r
+ if(g.hasStatement(el, l))\r
+ return false;\r
+ Resource back = prev(g, l, l);\r
+ g.denyStatement(back, l, l);\r
+ g.claim(back, l, el);\r
+ g.claim(el, l, l);\r
+ return true;\r
+ }\r
+\r
+ /**\r
+ * Adds a given elements <tt>el</tt> to the list <tt>l</tt>. Returns\r
+ * true, if the element was really added.\r
+ */\r
+ public static boolean addFirst(WriteGraph g, Resource l, Resource el) throws DatabaseException {\r
+ return addAfter(g, l, l, el);\r
+ }\r
+\r
+ public static boolean addAll(WriteGraph g, Resource l, Iterable<Resource> els) throws DatabaseException {\r
+ for(Resource r : els)\r
+ if(g.hasStatement(r, l))\r
+ return false;\r
+ Resource cur = prev(g, l, l);\r
+ g.denyStatement(cur, l, l);\r
+ for(Resource r : els) {\r
+ g.claim(cur, l, r);\r
+ cur = r;\r
+ }\r
+ g.claim(cur, l, l);\r
+ return true;\r
+ }\r
+\r
+ public static boolean addAllNew(WriteGraph g, Resource l, Iterable<Resource> els) throws DatabaseException {\r
+ Resource cur = prev(g, l, l);\r
+ Resource inv = g.getInverse(l);\r
+ g.deny(cur, l, inv, l);\r
+ for(Resource r : els) {\r
+ g.claim(cur, l, inv, r);\r
+ cur = r;\r
+ }\r
+ g.claim(cur, l, inv, l);\r
+ return true;\r
+ }\r
+\r
+ public static boolean addAfter(WriteGraph g, Resource l, Resource pos, Resource el) throws DatabaseException {\r
+ if(g.hasStatement(el, l))\r
+ return false;\r
+ Resource next = next(g, l, pos);\r
+ g.denyStatement(pos, l, next);\r
+ g.claim(pos, l, el);\r
+ g.claim(el, l, next);\r
+ return true;\r
+ }\r
+\r
+ public static boolean addBefore(WriteGraph g, Resource l, Resource pos, Resource el) throws DatabaseException {\r
+ if(g.hasStatement(el, l))\r
+ return false;\r
+ Resource prev = prev(g, l, pos);\r
+ g.denyStatement(prev, l, pos);\r
+ g.claim(prev, l, el);\r
+ g.claim(el, l, pos);\r
+ return true;\r
+ }\r
+\r
+ /**\r
+ * Removes a given elements <tt>el</tt> from the list <tt>l</tt>. Returns\r
+ * true, if the element was really removed.\r
+ */\r
+ public static boolean remove(WriteGraph g, Resource l, Resource el) throws DatabaseException {\r
+ Collection<Resource> nexts = g.getObjects(el, l);\r
+ if(nexts.size() == 0)\r
+ return false;\r
+ if(nexts.size() != 1)\r
+ throw new InvalidOrderedSetException("Invalid list element.");\r
+ Collection<Resource> prevs = g.getObjects(el, g.getInverse(l));\r
+ if(prevs.size() != 1)\r
+ throw new InvalidOrderedSetException("Invalid list element.");\r
+\r
+ for(Resource p : prevs)\r
+ for(Resource n : nexts) {\r
+ g.denyStatement(p, l, el);\r
+ g.denyStatement(el, l, n);\r
+ g.claim(p, l, n);\r
+ return true;\r
+ }\r
+ return true;\r
+ }\r
+\r
+ public static List<Resource> removeList(WriteGraph g, Resource l) throws DatabaseException {\r
+ List<Resource> els = toList(g, l);\r
+ for(Resource el : els)\r
+ g.deny(el, l);\r
+ g.deny(l, l);\r
+ Resource inv = g.getInverse(l);\r
+ g.deny(l);\r
+ g.deny(inv);\r
+ return els;\r
+ }\r
+\r
+ public static void replace(WriteGraph g, Resource l, Resource oldEl, Resource newEl) throws DatabaseException {\r
+ Collection<Resource> nexts = g.getObjects(oldEl, l);\r
+ if(nexts.size() != 1)\r
+ throw new InvalidOrderedSetException("Invalid list element.");\r
+ Collection<Resource> prevs = g.getObjects(oldEl, g.getInverse(l));\r
+ if(prevs.size() != 1)\r
+ throw new InvalidOrderedSetException("Invalid list element.");\r
+\r
+ for(Resource p : prevs)\r
+ for(Resource n : nexts) {\r
+ g.denyStatement(p, l, oldEl);\r
+ g.denyStatement(oldEl, l, n);\r
+ g.claim(p, l, newEl);\r
+ g.claim(newEl, l, n);\r
+ return;\r
+ }\r
+ }\r
+\r
+ /**\r
+ * Converts ordered set into a list.\r
+ */\r
+ public static List<Resource> toList(ReadGraph g, Resource l) throws DatabaseException {\r
+ ArrayList<Resource> ret = new ArrayList<Resource>();\r
+ Resource cur = l;\r
+ while(true) {\r
+ cur = next(g, l, cur);\r
+ if(cur.equals(l))\r
+ return ret;\r
+ ret.add(cur);\r
+ }\r
+ }\r
+\r
+ /**\r
+ * Converts ordered set into a list.\r
+ */\r
+ public static void forEach(AsyncReadGraph g, final Resource l, final AsyncMultiProcedure<Resource> procedure) {\r
+ g.asyncRequest(new ReadRequest() {\r
+\r
+ @Override\r
+ public void run(ReadGraph graph) throws DatabaseException {\r
+ for(Resource r : toList(graph, l))\r
+ procedure.execute(graph, r);\r
+ }\r
+\r
+ });\r
+ }\r
+\r
+ /**\r
+ * Creates an empty ordered set.\r
+ */\r
+ public static Resource create(WriteOnlyGraph g, Resource type) throws DatabaseException {\r
+ Layer0 l0 = g.getService(Layer0.class);\r
+ Resource l = g.newResource();\r
+ g.claim(l, l0.InstanceOf, null, type);\r
+ g.claim(l, l0.SubrelationOf, null, l0.HasNext);\r
+ Resource invL = g.newResource();\r
+ g.claim(invL, l0.SubrelationOf, null, l0.HasPrevious);\r
+ g.claim(l, l0.InverseOf, l0.InverseOf, invL);\r
+ g.claim(l, l, invL, l);\r
+ return l;\r
+ }\r
+\r
+ /**\r
+ * Creates an ordered set containing the given elements.\r
+ * It is assumed that the elements do not contain duplicates.\r
+ */\r
+ @Deprecated\r
+ public static Resource create(WriteOnlyGraph g, Resource type, Iterable<Resource> c) throws DatabaseException {\r
+ Layer0 l0 = g.getService(Layer0.class);\r
+ Resource l = g.newResource();\r
+ g.claim(l, l0.InstanceOf, null, type);\r
+ g.claim(l, l0.SubrelationOf, null, l0.HasNext);\r
+ Resource invL = g.newResource();\r
+ g.claim(invL, l0.SubrelationOf, null, l0.HasPrevious);\r
+ g.claim(l, l0.InverseOf, l0.InverseOf, invL);\r
+ Resource cur = l;\r
+ for(Resource r : c) {\r
+ g.claim(cur, l, invL, r);\r
+ cur = r;\r
+ }\r
+ g.claim(cur, l, invL, l);\r
+ return l;\r
+ }\r
+\r
+ public static Resource create(WriteOnlyGraph g, Resource type, String name, Iterable<Resource> c) throws DatabaseException {\r
+ return createExisting(g, g.newResource(), type, name, c);\r
+ }\r
+\r
+ public static Resource createExisting(WriteOnlyGraph g, Resource l, Resource type, String name, Iterable<Resource> c) throws DatabaseException {\r
+ Layer0 l0 = g.getService(Layer0.class);\r
+ g.claim(l, l0.InstanceOf, null, type);\r
+ g.claim(l, l0.SubrelationOf, null, l0.HasNext);\r
+ g.addLiteral(l, l0.HasName, l0.NameOf, l0.String, name, Bindings.STRING);\r
+ Resource invL = g.newResource();\r
+ g.claim(invL, l0.SubrelationOf, null, l0.HasPrevious);\r
+ g.addLiteral(invL, l0.HasName, l0.NameOf, l0.String, "Inverse", Bindings.STRING);\r
+ g.claim(l, l0.InverseOf, l0.InverseOf, invL);\r
+ g.claim(l, l0.ConsistsOf, l0.PartOf, invL);\r
+ Resource cur = l;\r
+ for(Resource r : c) {\r
+ g.claim(cur, l, invL, r);\r
+ cur = r;\r
+ }\r
+ g.claim(cur, l, invL, l);\r
+ return l;\r
+ }\r
+ \r
+ public static Resource create(WriteOnlyGraph g, Resource type, Resource ... c) throws DatabaseException {\r
+ Layer0 l0 = g.getService(Layer0.class);\r
+ Resource l = g.newResource();\r
+ g.claim(l, l0.InstanceOf, null, type);\r
+ g.claim(l, l0.SubrelationOf, null, l0.HasNext);\r
+ Resource invL = g.newResource();\r
+ g.claim(invL, l0.SubrelationOf, null, l0.HasPrevious);\r
+ g.claim(l, l0.InverseOf, l0.InverseOf, invL);\r
+ Resource cur = l;\r
+ for(Resource r : c) {\r
+ g.claim(cur, l, invL, r);\r
+ cur = r;\r
+ }\r
+ g.claim(cur, l, invL, l);\r
+ return l;\r
+ }\r
+\r
+ public static Resource createExisting(WriteGraph g, Resource l, Resource ... c) throws DatabaseException {\r
+ Layer0 l0 = Layer0.getInstance(g);\r
+ g.claim(l, l0.SubrelationOf, null, l0.HasNext);\r
+ Resource invL = g.newResource();\r
+ g.claim(invL, l0.SubrelationOf, null, l0.HasPrevious);\r
+ g.claim(l, l0.InverseOf, l0.InverseOf, invL);\r
+ Resource cur = l;\r
+ for(Resource r : c) {\r
+ g.claim(cur, l, invL, r);\r
+ cur = r;\r
+ }\r
+ g.claim(cur, l, invL, l);\r
+ return l;\r
+ }\r
+ \r
+// public static Resource create(GraphWriter graph, Resource type, Iterable<Resource> c) throws DatabaseException {\r
+// ReadGraph g = w.getGraph();\r
+// Builtins b = g.getBuiltins();\r
+// Resource l = w.create(type).get();\r
+// w.let(b.SubrelationOf, b.IsRelatedTo);\r
+// w.createInverse(l).let(b.SubrelationOf, g.getInverse(b.IsRelatedTo));\r
+//\r
+// Resource cur = l;\r
+// for(Resource r : c) {\r
+// w.stat(cur, l, r);\r
+// cur = r;\r
+// }\r
+// w.stat(cur, l, l);\r
+// return l;\r
+// }\r
+\r
+ public static class OrderedSetIterator implements ListIterator<Resource> {\r
+\r
+ ReadGraph g;\r
+ Resource l;\r
+ Resource prev;\r
+ Resource next;\r
+ int index;\r
+ boolean direction;\r
+\r
+ WriteGraph getWriteGraph() {\r
+ if (!(g instanceof WriteGraph))\r
+ throw new UnsupportedOperationException("");\r
+ return (WriteGraph) g;\r
+ }\r
+\r
+ public OrderedSetIterator(ReadGraph g, Resource l) throws DatabaseException {\r
+ this.g = g;\r
+ this.l = l;\r
+ this.prev = l;\r
+ this.next = OrderedSetUtils.next(g, l, l);\r
+ this.index = 0;\r
+ }\r
+\r
+ @Override\r
+ public boolean hasNext() {\r
+ return !next.equals(l);\r
+ }\r
+\r
+ @Override\r
+ public Resource next() {\r
+ prev = next;\r
+ try {\r
+ next = OrderedSetUtils.next(g, l, next);\r
+ } catch (DatabaseException e) {\r
+ throw new RuntimeDatabaseException(e);\r
+ }\r
+ ++index;\r
+ direction = true;\r
+ return prev;\r
+ }\r
+\r
+ @Override\r
+ public void remove() {\r
+ try {\r
+ WriteGraph wg = getWriteGraph();\r
+ if(direction) {\r
+ OrderedSetUtils.remove(wg, l, prev);\r
+ prev = OrderedSetUtils.prev(wg, l, next);\r
+ }\r
+ else {\r
+ OrderedSetUtils.remove(wg, l, next);\r
+ next = OrderedSetUtils.next(wg, l, prev);\r
+ }\r
+ } catch (DatabaseException e) {\r
+ throw new RuntimeDatabaseException(e);\r
+ }\r
+ }\r
+\r
+ @Override\r
+ public void add(Resource e) {\r
+ try {\r
+ WriteGraph wg = getWriteGraph();\r
+ wg.denyStatement(prev, l, next);\r
+ wg.claim(prev, l, e);\r
+ wg.claim(e, l, next);\r
+ prev = e;\r
+ } catch (DatabaseException ex) {\r
+ throw new RuntimeDatabaseException(ex);\r
+ }\r
+ }\r
+\r
+ @Override\r
+ public boolean hasPrevious() {\r
+ return !prev.equals(l);\r
+ }\r
+\r
+ @Override\r
+ public int nextIndex() {\r
+ return index;\r
+ }\r
+\r
+ @Override\r
+ public Resource previous() {\r
+ try {\r
+ next = prev;\r
+ prev = OrderedSetUtils.prev(g, l, prev);\r
+ --index;\r
+ direction = false;\r
+ return next;\r
+ } catch (DatabaseException ex) {\r
+ throw new RuntimeDatabaseException(ex);\r
+ }\r
+ }\r
+\r
+ @Override\r
+ public int previousIndex() {\r
+ return index-1;\r
+ }\r
+\r
+ @Override\r
+ public void set(Resource e) {\r
+ try {\r
+ WriteGraph wg = getWriteGraph();\r
+ if(direction) {\r
+ OrderedSetUtils.replace(wg, l, prev, e);\r
+ prev = e;\r
+ }\r
+ else {\r
+ OrderedSetUtils.replace(wg, l, next, e);\r
+ next = e;\r
+ }\r
+ } catch (DatabaseException ex) {\r
+ throw new RuntimeDatabaseException(ex);\r
+ }\r
+ }\r
+\r
+ }\r
+\r
+ public static ListIterator<Resource> iterator(ReadGraph g, Resource l) throws DatabaseException {\r
+ return new OrderedSetIterator(g, l);\r
+ }\r
+\r
+ public static boolean set(WriteGraph g, Resource l, Iterable<Resource> els) throws DatabaseException {\r
+\r
+ // Compute delta\r
+ Set<Pair<Resource,Resource>> removed = new HashSet<Pair<Resource,Resource>>();\r
+ Collection<Pair<Resource,Resource>> added = new ArrayList<Pair<Resource,Resource>>();\r
+ Resource cur = l;\r
+ do {\r
+ Resource temp = next(g, l, cur);\r
+ removed.add(new Pair<Resource,Resource>(cur, temp));\r
+ cur = temp;\r
+ } while(!cur.equals(l));\r
+\r
+ cur = l;\r
+ for(Resource temp : els) {\r
+ Pair<Resource,Resource> pair = new Pair<Resource, Resource>(cur, temp);\r
+ if(!removed.remove(pair))\r
+ added.add(pair);\r
+ cur = temp;\r
+ }\r
+\r
+ {\r
+ Pair<Resource,Resource> pair = new Pair<Resource, Resource>(cur, l);\r
+ if(!removed.remove(pair))\r
+ added.add(pair);\r
+ }\r
+\r
+ // Apply\r
+ if(added.isEmpty() && removed.isEmpty())\r
+ return false;\r
+ for(Pair<Resource,Resource> pair : removed)\r
+ g.denyStatement(pair.first, l, pair.second);\r
+ for(Pair<Resource,Resource> pair : added)\r
+ g.claim(pair.first, l, pair.second);\r
+ return true;\r
+ }\r
+\r
+ /**\r
+ * Retrieves the owner list the specified list element\r
+ * \r
+ * @param g\r
+ * @param el a possible element of a list of the specified type\r
+ * @param listBaseRelation a base relation of the list to look for\r
+ * @return\r
+ */\r
+ public static Resource getSingleOwnerList(ReadGraph g, Resource el, Resource listBaseRelation) throws DatabaseException {\r
+ Collection<Resource> result = getOwnerLists(g, el, listBaseRelation);\r
+ if (result.size() != 1)\r
+ throw new ValidationException(NameUtils.getSafeName(g, el) + " is part of " + result.size() + " lists of base type " + NameUtils.getSafeName(g, listBaseRelation) + ", expected only one list.");\r
+ return result.iterator().next();\r
+ }\r
+\r
+ public static Resource getSingleOwnerList(ReadGraph g, Resource el) throws DatabaseException {\r
+ Layer0 l0 = Layer0.getInstance(g);\r
+ Collection<Resource> result = getOwnerLists(g, el, l0.OrderedSet);\r
+ if (result.size() != 1)\r
+ throw new ValidationException(NameUtils.getSafeName(g, el) + " is part of " + result.size() + " lists of base type L0.OrderedSet, expected only one list.");\r
+ return result.iterator().next();\r
+ }\r
+ \r
+ public static Collection<Resource> getSubjects(ReadGraph g, Resource object) throws DatabaseException {\r
+ Collection<Resource> result = new ArrayList<Resource>(1);\r
+ Layer0 l0 = Layer0.getInstance(g);\r
+ for(Resource pred : g.getPredicates(object)) {\r
+ if(g.isInstanceOf(pred, l0.OrderedSet) && !pred.equals(object))\r
+ result.add(pred);\r
+ }\r
+ return result;\r
+ }\r
+\r
+ private static void forSubjects(ReadGraph g, Resource object, DbFunction<Resource, Boolean> consumer) throws DatabaseException {\r
+ for (Resource pred : g.getPredicates(object)) {\r
+ if (!pred.equals(object))\r
+ if (!consumer.apply(pred))\r
+ break;\r
+ }\r
+ }\r
+\r
+ /**\r
+ * Retrieves the owner list the specified list element\r
+ * \r
+ * @param g\r
+ * @param el a possible element of a list of the specified type\r
+ * @param listBaseRelation a base relation of the list to look for\r
+ * @return\r
+ */\r
+ public static Collection<Resource> getOwnerLists(ReadGraph g, Resource el, Resource listBaseRelation) throws DatabaseException {\r
+ Collection<Resource> result = null;\r
+ Collection<Resource> rs = getSubjects(g, el);\r
+ for (Resource r : rs) {\r
+ if (g.isInstanceOf(r, listBaseRelation)) {\r
+ if (result == null)\r
+ result = new ArrayList<Resource>(2);\r
+ result.add(r);\r
+ }\r
+ }\r
+ if (result == null)\r
+ result = Collections.emptyList();\r
+ return result;\r
+ }\r
+\r
+ private static class PossibleOwnerList implements DbFunction<Resource, Boolean> {\r
+ private ReadGraph graph;\r
+ private final Resource listBaseRelation;\r
+ public Layer0 L0;\r
+ public Resource result;\r
+\r
+ PossibleOwnerList(ReadGraph graph, Resource listBaseRelation) {\r
+ this.graph = graph;\r
+ this.listBaseRelation = listBaseRelation;\r
+ this.L0 = Layer0.getInstance(graph);\r
+ }\r
+\r
+ @Override\r
+ public Boolean apply(Resource t) throws DatabaseException {\r
+ Set<Resource> types = graph.getTypes(t);\r
+ if (types.contains(L0.OrderedSet) && types.contains(listBaseRelation)) {\r
+ if (result != null) {\r
+ result = null;\r
+ return false;\r
+ }\r
+ result = t;\r
+ }\r
+ return true;\r
+ }\r
+ }\r
+\r
+ /**\r
+ * Retrieves a possible single owner list the specified list element\r
+ * \r
+ * @param g\r
+ * @param el\r
+ * a possible element of a list of the specified type\r
+ * @param listBaseRelation\r
+ * a base relation of the list to look for\r
+ * @return <code>null</code> if there is zero or more than one owner lists\r
+ * with specified base relation\r
+ */\r
+ public static Resource getPossibleOwnerList(ReadGraph g, Resource el, Resource listBaseRelation) throws DatabaseException {\r
+ PossibleOwnerList proc = new PossibleOwnerList(g, listBaseRelation);\r
+ forSubjects(g, el, proc);\r
+ return proc.result;\r
+ }\r
+\r
+}\r