### Question:
AbstractBoundInstrument implements BoundInstrument { final void recordDouble(double value) { aggregator.recordDouble(value); } AbstractBoundInstrument(Aggregator aggregator); @Override final void unbind();  }### Answer:
@Test void recordDoubleValue() { TestBoundInstrument testBoundInstrument = new TestBoundInstrument(aggregator); Mockito.verifyNoInteractions(aggregator); Mockito.doNothing().when(aggregator).recordDouble(Mockito.anyDouble()); testBoundInstrument.recordDouble(1.2); Mockito.verify(aggregator, Mockito.times(1)).recordDouble(1.2); }