[
https://issues.apache.org/jira/browse/FLINK-4823?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15571746#comment-15571746
]
Sajeev Ramakrishnan commented on FLINK-4823:
--------------------------------------------
DataSet<Tuple2<String, VertexDTO>> vertices1 =
group.flatMap(new MapToVertex());
DataSet<Tuple2<String, VertexDTO>> vertices2 = user.flatMap(new
MapToVertex());
DataSet<Tuple2<String, VertexDTO>> vertices =
vertices1.union(vertices2);
DataSet<Tuple3<String,String,String>> edges =
member.flatMap(new MapToEdge());
Graph<String, VertexDTO, String> graph =
Graph.fromTupleDataSet(vertices,edges, env);
System.out.println("Vertices
"+graph.runVertexCentricIteration(new ComputeTraversal(expFile), null,
iterations).numberOfVertices());
static final class ComputeTraversal extends ComputeFunction<String,
VertexDTO, String, String> {
private static final long serialVersionUID =
4883900514255635602L;
String fileExpd;
FileWriter fw;
String DD="|";
public ComputeTraversal(String file) { fileExpd = file; }
public void preSuperstep() throws Exception { fw = new
FileWriter(fileExpd,true); System.out.println("iteration
"+getSuperstepNumber());}
public void postSuperstep() throws Exception { fw.close(); }
public void compute(Vertex<String, VertexDTO> v,
MessageIterator<String> msgIter) throws IOException {
List<String> targets = new ArrayList<String>();
if (getSuperstepNumber() == 1){
if (v.f1.visit && v.f1.type.equals("GROUP")){
if(v.f1.childList!=null &&
!v.f1.childList.isEmpty()){
for(String
child:v.f1.childList){
targets.add(child);
}
}
else
for (Edge<String, String> e :
getEdges())
targets.add(e.getTarget());
sendMessageToMembers(v, targets, null);
}
}
else {
if(v.f1.childList!=null && !v.f1.childList.isEmpty()){
for(String child:v.f1.childList){
targets.add(child);
}
}
else
for (Edge<String, String> e : getEdges())
targets.add(e.getTarget());
for (String msgIn : msgIter) {
if (!msgIn.contains(v.getId()+"\t")) { // prevent
cyclic graph
String msgOut =
sendMessageToMembers(v,targets,msgIn);
}
}
}
}
private String sendMessageToMembers(Vertex<String,VertexDTO> v,
List<String> targets, String msgIn) {
String msgOut = (msgIn==null ? "" : msgIn+">") +
v.getId()+"\t"+v.getValue().domain+"/"+v.getValue().name;
for (String t : targets) sendMessageTo(t,msgOut);
return msgOut;
}
}
static final class MapToEdge implements FlatMapFunction<InputT,
Tuple3<String, String,String>> {
/**
*
*/
private static final long serialVersionUID =
1930826776772888046L;
@Override
public void flatMap(InputT mem,Collector<Tuple3<String,
String,String>> out) throws Exception {
Tuple3<String,String,String> e = new
Tuple3<String,String,String>(mem.gKey+"",mem.mKey+"",mem.rKey+"");
out.collect(e);
}
}
// map combinedUserGroup data set to VertexDTO object
static final class MapToVertex implements FlatMapFunction<InputT,
Tuple2<String, VertexDTO>> {
private static final long serialVersionUID =
170886364461479813L;
@Override
public void flatMap(InputT vertex, Collector<Tuple2<String,
VertexDTO>> out) throws Exception {
VertexDTO VertexDTO = null;
//vertex.key is long. So making it as string
VertexDTO = new
VertexDTO(vertex.key+"",vertex.domain,vertex.accountName,vertex.memberType,vertex.childList,true);
out.collect(new Tuple2<String, VertexDTO>(VertexDTO.id,
VertexDTO));
}
}
static final class VertexDTO implements Serializable {
private static final long serialVersionUID =
-7095619486072713817L;
public String id = "";
public String domain = "";
public String name = "";
public String type = "";
public boolean visit;
Set<String> childList;
public VertexDTO() {}
public VertexDTO(String id, String domain, String account,
String type,Set<String> childList,boolean visit) {
this.id = id;
this.domain = domain;
this.name = account;
this.type = type;
this.childList = childList;
this.visit = visit;
}
public boolean equals(Object obj) {
return id.equals(((VertexDTO)obj).id);
}
}
> org.apache.flink.types.NullFieldException: Field 0 is null, but expected to
> hold a value
> ----------------------------------------------------------------------------------------
>
> Key: FLINK-4823
> URL: https://issues.apache.org/jira/browse/FLINK-4823
> Project: Flink
> Issue Type: Bug
> Components: Gelly
> Affects Versions: 1.1.0
> Environment: RHEL 6.6
> Reporter: Sajeev Ramakrishnan
> Priority: Blocker
>
> Team,
> We are getting NULL pointer exception while doing the vertex centric graph
> traversal.
> org.apache.flink.types.NullFieldException: Field 0 is null, but expected to
> hold a value.
> at
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:126)
> at
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:30)
> at
> org.apache.flink.runtime.plugable.SerializationDelegate.write(SerializationDelegate.java:56)
> at
> org.apache.flink.runtime.io.network.api.serialization.SpanningRecordSerializer.addRecord(SpanningRecordSerializer.java:83)
> at
> org.apache.flink.runtime.io.network.api.writer.RecordWriter.emit(RecordWriter.java:85)
> at
> org.apache.flink.runtime.operators.shipping.OutputCollector.collect(OutputCollector.java:65)
> at
> org.apache.flink.api.java.operators.JoinOperator$DefaultJoin$WrappingFlatJoinFunction.join(JoinOperator.java:572)
> at
> org.apache.flink.runtime.operators.JoinWithSolutionSetFirstDriver.run(JoinWithSolutionSetFirstDriver.java:196)
> at
> org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:486)
> at
> org.apache.flink.runtime.iterative.task.AbstractIterativeTask.run(AbstractIterativeTask.java:146)
> at
> org.apache.flink.runtime.iterative.task.IterationIntermediateTask.run(IterationIntermediateTask.java:92)
> at
> org.apache.flink.runtime.operators.BatchTask.invoke(BatchTask.java:351)
> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:584)
> at java.lang.Thread.run(Thread.java:745)
> Caused by: java.lang.NullPointerException
> at
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:122)
> at
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:30)
> at
> org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:124)
> ... 13 more
> All the parameters that I am passing for the vertex and edges are not null.
> Not able to find out the root cause.
> Thanks & Regards,
> Sajeev Ramakrishnan
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
