Simple Example NullPointerException

[ama542blake]

Per Dr. Lu's request, here is the code for the issue I am having running a simple example. GitHub does not allow .java file uploads in here, so I have posted the raw text. When I run it, I get a NullPointerException for each of the Task_Average_Column tasks that are in the workflow during execution on the local executor. import dataview.models.*;

public class Task_Average_Column extends Task { public static int instanceCount = 0;

// declare all I/O ports of the task
public Task_Average_Column() {
    super("Average column vector", "This task averages a column vector.");
    instanceCount++;
    // define input ports
    InputPort ins[] = new InputPort[1];
    ins[0] = new InputPort("in0", Port.DATAVIEW_MathVector, "Vector to be averaged");

    // define output ports
    OutputPort outs[] = new OutputPort[1];
    outs[0] = new OutputPort("out0", Port.DATAVIEW_double, "Result of averaging vector");
}

// this method performs the actual actions of the tasks
@Override
public void run() {
    System.out.println("RUN AVG COL");
    // step 1: read data from input ports
    DATAVIEW_MathVector inputVector = (DATAVIEW_MathVector) ins[0].read();

    // step 2: perform computation using data read from step 1
    // sum up all of the values in the vector
    double sum = 0;
    for(int i = 0; i < inputVector.length(); i++) {
        System.out.println("____________________________" + inputVector.get(i));
        sum += inputVector.get(i);
    }
    double average = sum / inputVector.length();
    // step 3: write data to output port
    outs[0].write(average);
}

}

Please let me know if any additional information is required.