Unable to fetch data from service in component in Angular 2 - service

Question

I am using Angular 2.0.0-beta.15. I am trying to get data from service in a component. Following is the piece of code in component.
import {Component} from 'angular2/core';
import {UserService} from '../services/user.service';
#Component({
selector: 'parent',
templateUrl: './views/parentUser.html',
providers: [UserService]
})
export class ParentUserComponent {
constructor(private _userService:UserService) {
this._userService.getCurrentUser().subscribe(data => console.log(data));
}
}
Now my UserService piece of code is
import {Injectable} from 'angular2/core';
import {Http, Response} from 'angular2/http';
import {Observable} from 'rxjs/Observable';
#Injectable()
export class UserService {
private currentUser = {
username: '',
role: '',
targetURL: ''
};
setCurrentUser(currentUser) {
this.currentUser.username = currentUser.username;
this.currentUser.role = currentUser.role;
this.currentUser.targetURL = currentUser.targetURL;
console.log('current User:' + JSON.stringify(this.currentUser));
}
getCurrentUser() {
return Observable.of(this.currentUser);
}
}
My boots.ts is as follows:
///<reference path="../../node_modules/angular2/typings/browser.d.ts"/>
import {bootstrap} from 'angular2/platform/browser';
import {provide} from 'angular2/core';
import {ROUTER_PROVIDERS, ROUTER_DIRECTIVES, RouteConfig, Location, LocationStrategy, HashLocationStrategy} from 'angular2/router';
import {AppComponent} from './app.component';
import {HTTP_PROVIDERS} from 'angular2/http';
import {UserService} from './services/user.service';
import 'rxjs/Rx';
bootstrap(AppComponent, [ROUTER_PROVIDERS, HTTP_PROVIDERS, provide(LocationStrategy, {useClass: HashLocationStrategy}), UserService]);
Now when i try to run my component. it throws error like
Error: Uncaught (in promise): No provider for a!
angular2-polyfills.js:528 Unhandled Promise rejection: No provider for a!
NoProviderError {message:"No provider for a!, stack: "Error: DI Exception↵ at NoProviderError.BaseExc…odules/angular2/bundles/angular2.dev.js:11788:19)", keys: Array[3], injectors: Array[3]}
Can somebody guide me?