Angular2 TypeScript REST client base class

HttpClient.ts

import { Http, Response, Headers, RequestOptions } from "@angular/http";
import * as Rx from "rxjs/Rx";

export abstract class HttpClient {
    constructor(private http: Http) {
    }
    
    protected referenceStringEncode(referenceString: string): string {
        return referenceString.replace("/", "%2F");
    }

    protected getRequest<TResult>(endpoint: string): Rx.Observable<TResult> {
        return this.http.get(endpoint)
                        .map(response => <TResult>response.json())
                        .catch(response => this.handleError(response));
    }

    protected deleteRequest<TResult>(endpoint: string): Rx.Observable<TResult> {
        return this.http.delete(endpoint)
            .map(response => <TResult>response.json())
            .catch(response => this.handleError(response));
    }

    protected postRequest<TInput, TResult>(endpoint: string, value: TInput): Rx.Observable<TResult> {
        let body = JSON.stringify(value);
        let headers = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: headers });

        return this.http.post(endpoint, body, options)
                        .map(response => <TResult>response.json())
                        .catch(response => this.handleError(response));
    }

    protected putRequest<TInput, TResult>(endpoint: string, value: TInput): Rx.Observable<TResult> {
        let body = JSON.stringify(value);
        let headers = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: headers });

        return this.http.put(endpoint, body, options)
            .map(response => <TResult>response.json())
            .catch(response => this.handleError(response));
    }

    protected patchRequest<TInput, TResult>(endpoint: string, value: TInput): Rx.Observable<TResult> {
        let body = JSON.stringify(value);
        let headers = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: headers });

        return this.http.patch(endpoint, body, options)
            .map(response => <TResult>response.json())
            .catch(response => this.handleError(response));
    }

    private handleError<TResult>(response: Response) {
        return Rx.Observable.throw(response.json());
    }
}