abstract class Abstraction {
  protected Implementor implementor;

  public void setImplementor(Implementor implementor) {
    this.implementor = implementor;
  }
  abstract public void operation();
}

public class RefinedAbstraction extends Abstraction {
  public void operation() {
    implementor.operation();
  }
}

public interface Implementor {
  public void operation();
}

public class ConcreteImplementorA implements Implementor {
  public void operation() {
    System.out.println("ConcreteImplementorA operationメソッド");
  }
}

public class ConcreteImplementorB implements Implementor {
  public void operation() {
    System.out.println("ConcreteImplementorB operationメソッド");
  }
}

public class Client {
  public static void main(String[] args) {
    Abstraction abstraction = new RefinedAbstraction();

    abstraction.setImplementor(new ConcreteImplementorA());
    abstraction.operation();

    abstraction.setImplementor(new ConcreteImplementorB());
    abstraction.operation();
  }
}

C:\JavaHello\Bridge>java Client
ConcreteImplementorA operationメソッド
ConcreteImplementorB operationメソッド

C:\JavaHello\Bridge>