Re: Couldn't instantiate

[Carmen Manzulli]

ok; i've done what you have told me...but now i've got this problem..

ava.lang.Throwable: Child Error
        at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:271)
Caused by: java.io.IOException: Task process exit with nonzero status of 1.
        at org.apache.hadoop.mapred.TaskRunner.run(TaskRunner.java:258)

this is my Computation code:
import org.apache.giraph.GiraphRunner;
import org.apache.giraph.graph.BasicComputation;
import org.apache.giraph.graph.Vertex;
import org.apache.giraph.edge.Edge;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.util.ToolRunner;



public class SimpleSelectionComputation extends
BasicComputation<Text,NullWritable,Text,NullWritable> {
        
@Override
public void compute(Vertex<Text,NullWritable,Text>
vertex,Iterable<NullWritable> messages){
        
        
        Text source = new Text("http://dbpedia.org/resource/1040s";);
        
        if (getSuperstep()==0)
        {
                if(vertex.getId()==source)
                {
                        System.out.println("il soggetto "+vertex.getId()+" ha i 
seguenti
predicati e oggetti:");
                        for(Edge<Text,Text> e : vertex.getEdges())
                        {
                                
System.out.println(e.getValue()+"\t"+e.getTargetVertexId());
                        }
                }
                vertex.voteToHalt();
        }
        
}

public static void main(String[] args) throws Exception {
    System.exit(ToolRunner.run(new GiraphRunner(), args));
  }

        
}