Author: ito
Date: Mon Feb 28 12:41:22 2011
New Revision: 1075314
URL: http://svn.apache.org/viewvc?rev=1075314&view=rev
Log:
CLEREZZA-431: triple <listUri, owl:sameAs, rdf:Nil> will not be added in the
constructor
Modified:
incubator/clerezza/trunk/parent/rdf.utils/src/main/java/org/apache/clerezza/rdf/utils/RdfList.java
Modified:
incubator/clerezza/trunk/parent/rdf.utils/src/main/java/org/apache/clerezza/rdf/utils/RdfList.java
URL:
http://svn.apache.org/viewvc/incubator/clerezza/trunk/parent/rdf.utils/src/main/java/org/apache/clerezza/rdf/utils/RdfList.java?rev=1075314&r1=1075313&r2=1075314&view=diff
==============================================================================
---
incubator/clerezza/trunk/parent/rdf.utils/src/main/java/org/apache/clerezza/rdf/utils/RdfList.java
(original)
+++
incubator/clerezza/trunk/parent/rdf.utils/src/main/java/org/apache/clerezza/rdf/utils/RdfList.java
Mon Feb 28 12:41:22 2011
@@ -27,13 +27,11 @@ import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
-import java.util.concurrent.locks.Lock;
import org.apache.clerezza.rdf.core.BNode;
import org.apache.clerezza.rdf.core.NonLiteral;
import org.apache.clerezza.rdf.core.Resource;
import org.apache.clerezza.rdf.core.TripleCollection;
import org.apache.clerezza.rdf.core.UriRef;
-import org.apache.clerezza.rdf.core.access.LockableMGraph;
import org.apache.clerezza.rdf.core.impl.TripleImpl;
import org.apache.clerezza.rdf.core.serializedform.Serializer;
import org.apache.clerezza.rdf.core.serializedform.SupportedFormat;
@@ -72,9 +70,7 @@ public class RdfList extends AbstractLis
private boolean totallyExpanded = false;
/**
- * Get a list for the specified resource. If the resource does not have
- * rdf:first and rdf:rest properties an empty list is created by
- * specifying that the resource is owl:sameAs rdf:nil.
+ * Get a list for the specified resource.
*
* If the list is modified using the created instance
* <code>listResource</code> will always be the first list.
@@ -85,40 +81,11 @@ public class RdfList extends AbstractLis
public RdfList(NonLiteral listResource, TripleCollection tc) {
firstList = listResource;
this.tc = tc;
- boolean addNilStmt;
- if (tc instanceof LockableMGraph) {
- LockableMGraph lg = (LockableMGraph) tc;
- final Lock readLock = lg.getLock().readLock();
- readLock.lock();
- try {
- addNilStmt = listIncomplete(listResource);
- } finally {
- readLock.unlock();
- }
- } else {
- addNilStmt = listIncomplete(listResource);
- }
- if (addNilStmt) {
- tc.add(new TripleImpl(listResource, OWL.sameAs,
RDF_NIL));
- }
- }
- private boolean listIncomplete(NonLiteral listResource) {
- if (!tc.filter(listResource, RDF.first, null).hasNext()) {
- if (!tc.filter(listResource, OWL.sameAs,
RDF_NIL).hasNext()) {
- return true;
- }
- }
- return false;
}
/**
- * Get a list for the specified resource node. If the resource node
does not
- * have rdf:first and rdf:rest properties an empty list is created by
- * specifying that the resource is owl:sameAs rdf:nil.
- *
- * If the list is modified using the created instance
- * <code>listResource</code> will always be the first list.
+ * Get a list for the specified resource node.
*
* @param listNode
*/
@@ -126,6 +93,28 @@ public class RdfList extends AbstractLis
this((NonLiteral)listNode.getNode(), listNode.getGraph());
}
+ /**
+ * Creates an empty RdfList by writing a triple
+ * "{@code listResource} owl:sameAs rdf.nil ." to {@code tc}.
+ *
+ * @param listResource
+ * @param tc
+ * @return an empty rdf:List.
+ * @throws IllegalArgumentException
+ * if the provided {@code listResource} is a non-empty
rdf:List.
+ */
+ public static RdfList createEmptyList(NonLiteral listResource,
TripleCollection tc)
+ throws IllegalArgumentException {
+
+ if (!tc.filter(listResource, RDF.first, null).hasNext()) {
+ RdfList list = new RdfList(listResource, tc);
+ list.tc.add(new TripleImpl(listResource, OWL.sameAs,
RDF_NIL));
+ return list;
+ } else {
+ throw new IllegalArgumentException(listResource + "is a
non-empty rdf:List.");
+ }
+ }
+
private void expandTill(int pos) {
if (totallyExpanded) {
return;
@@ -135,7 +124,7 @@ public class RdfList extends AbstractLis
currentList = listList.get(listList.size()-1);
} else {
currentList = firstList;
- if (tc.filter(currentList, OWL.sameAs,
RDF_NIL).hasNext()) {
+ if (!tc.filter(currentList, RDF.first, null).hasNext())
{
return;
}
listList.add(currentList);
