The idea behind the adapter design pattern is to take two classes that are not Liskov$-$compatible due to their public interfaces and make them so by writing an intermediate layer of software that $$translates$$ between one set of method calls to another $($with a little extra work$).$

Consider a system that delivers notifications to its users. The Notification interface looks like this:

public interface Notification $\{$ void setRecipient$($User recipient$)$; void setSender$($User sender$)$; void setMessage$($String message$)$; String getMessage$()$; $\}$