Angular 2. Http service not working : **It`s my HttpService.ts**

    import { Injectable } from "@angular/core";
    import { Http, Response } from "@angular/http";
    import 'rxjs/add/operator/map';

    @Injectable()
    export class HttpService {
       constructor (private http: Http) {}

        getData() {
            return this.http.get('http://blog_api.org/v1/posts')
                .map((response: Response) => response.json());
    }
}

**It`s my app.component.ts**

    import { Component } from '@angular/core';
    import { HttpService } from '../app/services/HttpService'
    @Component({
        selector: 'my-app',
        template: `Hello`,
    })
    export class AppComponent  {
        constructor (private httpService: HttpService) {};

        ngOnInit() {
            this.httpService.getData()
                .subscribe(
                    data => console.log(data)
                )
        }
    }

**When I running app, I get error:**

EXCEPTION: No provider for HttpService!
Help me please?