Java Programming

I'm getting this error:
Implicit super constructor WeightedMeasurement is undefined. Must explicity invoke another constructor.

WeightedMeasurement is an abstract class in apache.commons.math. So no, it does not have a constructor as such, though it does define 2:

WeightedMeasurement(double weight, double measuredValue)
WeightedMeasurement(double weight, double measuredValue, boolean ignored)

So I I tried to override like so:

import org.apache.commons.math.estimation.WeightedMeasurement;
public class MyWeightedMeasurement extends WeightedMeasurement {
	public MyWeightedMeasurement() {
		String s = new String();
	}

	public MyWeightedMeasurement(double weight, double measuredValue, int x) {
		new MyWeightedMeasurement();
	}
}

but no dice.
What do I need to do?
I searched, but didn't find any help.