You can extend only one class .. but you can implement may class
public virtual class Marker {
public virtual void write() {
System.debug('Writing some text.');
}
public virtual Double discount() {
return .05;
}
}
Then create the YellowMarker class, which extends the Marker class.
// Extension for the Marker class
public class YellowMarker extends Marker {
public override void write() {
System.debug('Writing some text using the yellow marker.');
}
}
Now you can event your AnotherMarker that extends YellowMarker
// Extension for the Marker class
public class OtherMarker extends YellowMarker {
public override void write() {
System.debug('Writing some text using the yellow marker.');
}
}
THIS IS NOT POSSABLE
// Extension for the Marker class
public class OtherMarker extends YellowMarker, Marker{
public override void write() {
System.debug('Writing some text using the yellow marker.');
}
}
Then create the YellowMarker class, which extends the Marker class.
Now you can event your AnotherMarker that extends YellowMarker
THIS IS NOT POSSABLE