Extending HeaterController

class VariableController extends HeaterController {

public static final int DefaultLevel = 16, ...;

public int getLevel(){

return getHeater().getTemperature();

}

public void setLevel(int level) throws RuntimeException {

if((MinLevel <= level) && (level <= MaxLevel)){

getHeater().setTemperature(level);

}

else{

throw new RuntimeException(

"Illegal level setting: "+level);

}