What is an adapter pattern?

The Bridge design pattern allows you to separate the abstraction from the implementation. It is a structural design pattern. 

When should I use the adapter pattern?

The adapter pattern should be used when:

• separate the abstraction from the implementation so that it can be easily extended independently of each other.
• Both Abstraction and Implementation should be extended with subclasses.
• Use where changes made in the implementation do not affect the client side.

How to implement

Device interface

interface IDevice {
  getChannel();
}

Device abstract class:

export abstract class Device implements IDevice {
  protected _remote: IRemote;

  constructor(remote) {
    this._remote = remote;
  }

  abstract getChannel();
}

Tv device class

export class Television extends Device {
  constructor(remote: IRemote) {
    super(remote);
  }

  override getChannel() {
    return this._remote.changeChannel();
  }
}

Radio device class:

export class Radio extends Device {
  constructor(remote: IRemote) {
    super(remote);
  }

  override getChannel() {
    return this._remote.changeChannel();
  }
}

Remote interface

interface IRemote {
  changeChannel();
}

RemoteTv class:

export class RemoteTv implements IRemote {
  changeChannel() {
    return 'Remote tv change channel';
  }
}

RemoteRadio class:

export class RemoteRadio implements IRemote {
  changeChannel() {
    return 'Remote radio change channel';
  }
}

The client code:

function client() {
  const tv = new Television(new RemoteTv());
  const radio = new Radio(new RemoteRadio());

  console.log(tv.getChannel());
  console.log(radio.getChannel());
}

client();

Result:

Remote tv change channel
Remote radio change channel

Pros and Cons

Pros:

• Easily to maintain.
• Easy to expand.
• Hidding implements from clientside.
• Reduce the number of classes that are not necessary.
• Reduce dependency between abstraction vs implementation

Cons:

• You might make the code more complicated by applying the pattern to a highly cohesive class.



Wrapping Up

Thank you for reading, and happy coding!

I hope this article will help make the concepts of the Bridge Pattern