GraphStream - Problems using netstream

Question

I'm using a standard example, given in the following code, but the java application returns the following error:

[//NetStreamDecoder | NetStreamReceiver: Don't know this command: 0]

I've been compiling the java example with:

javac -cp lib/gs-core-1.2.jar:. ExampleReceiver.java

while the C++ sender is the one provided in https://github.com/graphstream/gs-netstream. How could I see the update in the Java application? Thanks in advance.

Example.java

import java.io.IOException;
import java.net.UnknownHostException;

import org.graphstream.graph.Graph;
import org.graphstream.graph.implementations.MultiGraph;
import org.graphstream.stream.netstream.packing.Base64Unpacker;
import org.graphstream.stream.netstream.NetStreamReceiver;
import org.graphstream.stream.thread.ThreadProxyPipe;

public class ExampleReceiver {

    public static void main(String[] args) throws UnknownHostException, IOException, InterruptedException {

        Graph g = new MultiGraph("G",false,true);
        g.display();
        NetStreamReceiver net = new NetStreamReceiver(2001);

        ThreadProxyPipe pipe = net.getDefaultStream();
        pipe.addSink(g);
        while (true) {
            pipe.pump();
            Thread.sleep(100);
        }
    }
}

gs-netstream/cpp/src/netstream-main.cpp

void events_test(){
  string source_id="C++_netstream_test";
  long time_id=0L;
  NetStreamSender stream("localhost", 2001);
  stream.addNode(source_id, time_id++, "node0");
  stream.addEdge(source_id, time_id++, "edge", "node0", "node1", true);
  stream.addNodeAttribute(source_id, time_id++, "node0","nodeAttribute", 0);
  stream.changeNodeAttribute(source_id, time_id++, "node0","nodeAttribute",0, 1);
  stream.removeNodeAttribute(source_id, time_id++, "node0","nodeAttribute");
  stream.addEdgeAttribute(source_id, time_id++, "edge","edgeAttribute", 0);
  stream.changeEdgeAttribute(source_id, time_id++, "edge","edgeAttribute", 0,1);
  stream.removeEdgeAttribute(source_id, time_id++, "edge","edgeAttribute");
  stream.addGraphAttribute(source_id, time_id++, "graphAttribute", 0);
  stream.changeGraphAttribute(source_id, time_id++, "graphAttribute", 0, 1);
  stream.removeGraphAttribute(source_id, time_id++, "graphAttribute");
  stream.stepBegins(source_id, time_id++, 1.1);
  stream.removeEdge(source_id, time_id++, "edge");
  stream.removeNode(source_id, time_id++, "node0");
  stream.graphClear(source_id, time_id++);
}

Answer 1

The C++ and python version of NetStream are not in sync with the implementation in gs-core version 1.2. We have to update the C++ and python implementations.

In the mean time you can use an older version of gs-core. I suggest checking out revision a3f70d2 from the github repository.