dependency_injection_refactor2_example.java

/* Add device interface */
interface Device{ }

interface VideoCable{ 
  public void connect(Device device); 
}

class Laptop implements Device{}

class DisplayPortCable implements VideoCable{
  public void connect(Device device){
    connectedDevice = device;
  }

  private Device connectedDevice; 
}

class Monitor{
  public Monitor(VideoCable videoConnector){
     this.videoConnector = videoConnector;
  }

  public void connectToDevice(Device device){
    videoConnector.connect(device);
  }

  private VideoCable videoConnector; 
}