Hello everyone,

i have one problem that often occurs as i try to run ProSys Java Evaluation Stack for a longer time period with multiple client session:

below is my code:

for the initialization of UaVariableNode:

private void createCartesianForceValues() throws StatusException {

CartesianForceValues = new UaVariableNode[3];

final String[] name = { “ForceInX”, “ForceInY”, “ForceInZ” };
final NodeId[] variableId = new NodeId[3];

variableId[0] = new NodeId(getNamespaceIndex(), name[0]);
variableId[1] = new NodeId(getNamespaceIndex(), name[1]);
variableId[2] = new NodeId(getNamespaceIndex(), name[2]);
CartesianForceValues[0] = new PlainVariable(this,
variableId[0], name[0], Locale.ENGLISH);
CartesianForceValues[0].setValue(Double.valueOf(0));
CartesianForceValues[0].setValueRank(-1);
CartesianForceValues[0].setBrowseName(new QualifiedName(name[0]));
CartesianForceValues[0].setAccessLevel(AccessLevel.READONLY);

CartesianForceValues[1] = new PlainVariable(this,
variableId[1], name[1], Locale.ENGLISH);
CartesianForceValues[1].setValue(Double.valueOf(0));
CartesianForceValues[1].setValueRank(-1);
CartesianForceValues[1].setBrowseName(new QualifiedName(name[1]));
CartesianForceValues[1].setAccessLevel(AccessLevel.READONLY);

CartesianForceValues[2] = new PlainVariable(this,
variableId[2], name[2], Locale.ENGLISH);
CartesianForceValues[2].setValue(Double.valueOf(0));
CartesianForceValues[2].setValueRank(-1);
CartesianForceValues[2].setBrowseName(new QualifiedName(name[2]));
CartesianForceValues[2].setAccessLevel(AccessLevel.READONLY);

this.addNodeAndReference(ExternalCartesianForceOnFlange,
CartesianForceValues[0], Identifiers.HasComponent);

this.addNodeAndReference(ExternalCartesianForceOnFlange,
CartesianForceValues[1], Identifiers.HasComponent);

this.addNodeAndReference(ExternalCartesianForceOnFlange,
CartesianForceValues[2], Identifiers.HasComponent);

}
To update the value of UaVariable Node
public void setCartesianForceValues(Vector forces) throws StatusException {

CartesianForceValues[0].updateValue(Double.valueOf(forces.getX()));
CartesianForceValues[1].updateValue(Double.valueOf(forces.getY()));
CartesianForceValues[2].updateValue(Double.valueOf(forces.getZ()));

Double[] force = { forces.getX(), forces.getY(), forces.getZ() };
Variant variant = new Variant(force);
DataValue dataValue = new DataValue(new Variant(new Double[3]));
dataValue.setValue(variant);
CartesianForceValuesInArray.updateValue(dataValue);
setCartesianForceManitude(forces.length());

}

At the code row:
“CartesianForceValues[0].updateValue(Double.valueOf(forces.getX()));” there is an Nullpointer Exception.

2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] java.lang.NullPointerException
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.MonitoredDataItem.isAccessible(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.MonitoredDataItem.notifyDataChange(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.MonitoredDataItem.notifyDataChange(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.j.onDataChange(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.nodes.ServerNode.fireDataChange(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.nodes.ServerNode.dataChange(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.nodes.UaVariableNode.setValue(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.nodes.UaVariableNode.updateValue(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.nodes.PlainVariable.updateValue(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at com.prosysopc.ua.server.nodes.UaVariableNode.updateValue(Unknown Source)
2016-09-12 14:09:42,175 ERROR [.. pool-1-thread-1] at server.LBRNodeManager.setCartesianForceValues(LBRNodeManager.java:1969)