public MockPowerPanel(int numChannels){
  channels=new ArrayList<>(numChannels);
  for (int i=0; i != numChannels; ++i) {
    channels.add(new MockCurrentSensor());
  }
}

public MockPowerPanel ( int numChannels ) { channels = new ArrayList < > ( numChannels ) ; for ( int i = 0 ; i != numChannels ; ++ i ) { channels . add ( new MockCurrentSensor ( ) ) ; } }
create a mock power panel with the specified number of channels .
