// represents general abstract elements of musical instruments
public abstract class MusicalInstrument {


    protected String key;

    /* constructors -----------------------------------------*/
    public MusicalInstrument() {
        key = "C";
    }
    
    /* constructor with parameter */
    public MusicalInstrument(String newKey) {
        this();
        setKey(newKey);
    }
    

    /* mutators and accessors for instance variables -------*/
    
    public void setKey(String newKey) {
        key = newKey;
    }
    
    public String getKey() {
        return key;
    }
    
    /* abstract methods ---------------------------------*/
    
    
    public abstract void play();

    public abstract void prepare();


    
    /* toString
        create String representation */
    public String toString() {
        return "("+key+")";
    }
    
    

}