The Adapter pattern allows incompatible interfaces to work together by converting the interface of one class into another interface clients expect. The document describes an example where a BotLeader interface with a fireBullets() method needs to work with a Ralph class that has a smash() method. An Adapter class is created that implements the BotLeader interface and contains a Ralph object. The Adapter's fireBullets() method calls the Ralph object's smash() method, adapting the Ralph interface to the expected BotLeader interface. This allows different classes to work together even if their interfaces don't match directly.

1. Name : Adapter
Problem : How to resolve incompatible
interfaces, or provide a stable interface to
similar components with different interfaces?
Solution : Convert the original interface of a
component into another interface, through an
intermediate adapter object.

3. fireBullets()

4. fireBullets()

5. fireBullets()
Smash()

6. fireBullets()
Smash()
fireBullets()

7. public interface BotLeader {
public void fireBullets();
}
Public class Bot implements BotLeader {
@Override
public void fireBullets() {
if (countBullet() < 0) { reload(); }
System.out.println(“1 bullet fired”);
bulletCount--;
}
}

8. public class Ralph {
public void smash() {
moveHandsUp();
moveHandsDownWithForce();
}
}
public class RalphAdapter implements BotLeader {
private ralph;
public RalphAdapter (Ralph activeRalph) {
this.ralph = activeRalph;
}
@Override
public void fireBullets() {
ralph.smash();
}
}

9. public class StartGame {
public void main() {
Bot soldier = new Bot();
Ralph raf = new Ralph();
RalphAdapter rafAdapter = new RalphAdapter(raf);
System.out.println(“Commander commands fireBullets()”);
soldier.fireBullets();
rafAdapter.fireBullets();
System.out.println(“All cyborgs are killed!!! Medal won!!! ”);
}
}