Author: reto
Date: Wed Nov 30 13:52:35 2011
New Revision: 1208428
URL: http://svn.apache.org/viewvc?rev=1208428&view=rev
Log:
CLEREZZA-661: sorting by hash and fall back to toString for equals hashes
Modified:
incubator/clerezza/trunk/parent/rdf.rdfjson/src/main/java/org/apache/clerezza/rdf/rdfjson/serializer/RdfJsonSerializingProvider.java
Modified:
incubator/clerezza/trunk/parent/rdf.rdfjson/src/main/java/org/apache/clerezza/rdf/rdfjson/serializer/RdfJsonSerializingProvider.java
URL:
http://svn.apache.org/viewvc/incubator/clerezza/trunk/parent/rdf.rdfjson/src/main/java/org/apache/clerezza/rdf/rdfjson/serializer/RdfJsonSerializingProvider.java?rev=1208428&r1=1208427&r2=1208428&view=diff
==============================================================================
---
incubator/clerezza/trunk/parent/rdf.rdfjson/src/main/java/org/apache/clerezza/rdf/rdfjson/serializer/RdfJsonSerializingProvider.java
(original)
+++
incubator/clerezza/trunk/parent/rdf.rdfjson/src/main/java/org/apache/clerezza/rdf/rdfjson/serializer/RdfJsonSerializingProvider.java
Wed Nov 30 13:52:35 2011
@@ -43,40 +43,48 @@ import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
/**
- * A {@link org.apache.clerezza.rdf.core.serializedform.SerializingProvider}
for rdf/json.
+ * A {@link org.apache.clerezza.rdf.core.serializedform.SerializingProvider}
for
+ * rdf/json.
*
* This implementation is based on first sorting the triples within the parsed
- * {@link TripleCollection} based on the {@link #SUBJECT_COMPARATOR
subject}.<p>
+ * {@link TripleCollection} based on the {@link #SUBJECT_COMPARATOR subject}.
+ * <p>
* The serialization is done on a subject scope. Meaning that all triples for a
- * subject are serialized and instantly written to the provided
- * {@link OutputStream}.<p>
- * 'UFT-8' is used as encoding to write the data.
+ * subject are serialized and instantly written to the provided
+ * {@link OutputStream}.
+ * <p>
+ * 'UFT-8' is used as encoding to write the data.
*
* @author tio, hasan, rwesten
*/
-@Component(immediate=true)
+@Component(immediate = true)
@Service(SerializingProvider.class)
@SupportedFormat(SupportedFormat.RDF_JSON)
public class RdfJsonSerializingProvider implements SerializingProvider {
@SuppressWarnings("unchecked")
@Override
- public void serialize(OutputStream serializedGraph, TripleCollection
tc, String formatIdentifier) {
- if (tc.isEmpty()) { //ensure writing an empty element in case
of an empty collection
+ public void serialize(OutputStream serializedGraph, TripleCollection tc,
+ String formatIdentifier) {
+ if (tc.isEmpty()) { // ensure writing an empty element in case
of an
+ // empty collection
try {
- serializedGraph.write(new
JSONObject().toJSONString().getBytes("UTF-8"));
+ serializedGraph.write(new
JSONObject().toJSONString().getBytes(
+ "UTF-8"));
} catch (IOException e) {
- throw new IllegalStateException("Exception
while writing to parsed OutputStream", e);
+ throw new IllegalStateException(
+ "Exception while writing to
parsed OutputStream", e);
}
return;
}
BNodeManager bNodeMgr = new BNodeManager();
BufferedWriter out;
try {
- out = new BufferedWriter(
- new OutputStreamWriter(serializedGraph,
"UTF-8"));
+ out = new BufferedWriter(new
OutputStreamWriter(serializedGraph,
+ "UTF-8"));
} catch (UnsupportedEncodingException e) {
- throw new IllegalStateException("Encoding 'UTF-8' is
not supported by this System", e);
+ throw new IllegalStateException(
+ "Encoding 'UTF-8' is not supported by
this System", e);
}
Triple[] sortedTriples = tc.toArray(new Triple[tc.size()]);
Arrays.sort(sortedTriples, SUBJECT_COMPARATOR);
@@ -87,23 +95,26 @@ public class RdfJsonSerializingProvider
Map<UriRef, JSONArray> predicateValues = new HashMap<UriRef,
JSONArray>();
JSONObject jSubject = new JSONObject();
try {
- out.write("{"); //start the root object
+ out.write("{"); // start the root object
for (int i = 0; i < sortedTriples.length; i++) {
triple = sortedTriples[i];
boolean subjectChange =
!triple.getSubject().equals(subject);
if (subjectChange) {
if (subject != null) {
- //write the predicate values
- for (Entry<UriRef, JSONArray>
predicates : predicateValues.entrySet()) {
-
jSubject.put(predicates.getKey().getUnicodeString(), predicates.getValue());
+ // write the predicate values
+ for (Entry<UriRef, JSONArray>
predicates : predicateValues
+ .entrySet()) {
+ jSubject.put(
+
predicates.getKey().getUnicodeString(),
+
predicates.getValue());
}
- //write subject
+ // write subject
out.write(JSONObject.toString(subjectStr, jSubject));
out.write(",");
- jSubject.clear(); //just clear
+ jSubject.clear(); // just clear
predicateValues.clear();
}
- //init next subject
+ // init next subject
subject = triple.getSubject();
if (subject instanceof BNode) {
subjectStr =
bNodeMgr.getBNodeId((BNode) subject);
@@ -120,15 +131,18 @@ public class RdfJsonSerializingProvider
values.add(writeObject(bNodeMgr,
triple.getObject()));
}
if (subjectStr != null) {
- for (Entry<UriRef, JSONArray> predicates :
predicateValues.entrySet()) {
-
jSubject.put(predicates.getKey().getUnicodeString(), predicates.getValue());
+ for (Entry<UriRef, JSONArray> predicates :
predicateValues
+ .entrySet()) {
+
jSubject.put(predicates.getKey().getUnicodeString(),
+ predicates.getValue());
}
out.write(JSONObject.toString(subjectStr,
jSubject));
}
- out.write("}");//end the root object
+ out.write("}");// end the root object
out.flush();
} catch (IOException e) {
- throw new IllegalStateException("Exception while
writing on the parsed OutputStream", e);
+ throw new IllegalStateException(
+ "Exception while writing on the parsed
OutputStream", e);
}
}
@@ -140,7 +154,7 @@ public class RdfJsonSerializingProvider
String bNodeId = bNodeMap.get(node);
if (bNodeId == null) {
bNodeId = "_:b" + ++counter;
- bNodeMap.put((BNode)node, bNodeId);
+ bNodeMap.put((BNode) node, bNodeId);
}
return bNodeId;
}
@@ -149,9 +163,11 @@ public class RdfJsonSerializingProvider
/**
* Converts the {@link Resource object} of an triple to JSON
*
- * @param bNodeMgr used to lookup {@link BNode} instances
- * @param object the object of the triple
- * @return the JSON representation of parsed object
+ * @param bNodeMgr
+ * used to lookup {@link BNode} instances
+ * @param object
+ * the object of the triple
+ * @return the JSON representation of parsed object
*/
@SuppressWarnings("unchecked")
private JSONObject writeObject(BNodeManager bNodeMgr, Resource object) {
@@ -179,18 +195,28 @@ public class RdfJsonSerializingProvider
}
return jObject;
}
-
+
/**
- * Compares only the subjects of the triples. If they are equals
<code>0</code>
- * is returned. This will ensure that all triples with the same
subjects are
- * sorted correctly. However it does not sort predicates and objects!
+ * Compares only the subjects of the triples. If they are equals
+ * <code>0</code> is returned. This will ensure that all triples with
the
+ * same subjects are sorted correctly. However it does not sort
predicates
+ * and objects!
*/
public static final Comparator<Triple> SUBJECT_COMPARATOR = new
Comparator<Triple>() {
@Override
public int compare(Triple a, Triple b) {
- return a.getSubject().equals(b.getSubject()) ? 0
- :
a.getSubject().toString().compareTo(b.getSubject().toString());
+ return compare(a.getSubject(), b.getSubject());
}
+
+ private int compare(NonLiteral a, NonLiteral b) {
+ int hashA = a.hashCode();
+ int hashB = b.hashCode();
+ if (hashA != hashB) {
+ return hashB - hashA;
+ }
+ return a.toString().compareTo(b.toString());
+ }
+
};
}
