How to use the @harbor/ui.isEmpty function in @harbor/ui

public save(): void {
        let changes = this.getChanges();
        if (!isEmpty(changes)) {
            this.onGoing = true;
            this.configService.saveConfiguration(changes)
                .subscribe(response => {
                    this.onGoing = false;
                    // refresh allConfig
                    this.refreshAllconfig.emit();
                    this.msgHandler.showSuccess('CONFIG.SAVE_SUCCESS');
                }, error => {
                    this.onGoing = false;
                    this.msgHandler.handleError(error);
                });
        } else {
            // Inprop situation, should not come here
            console.error('Save abort because nothing changed');
        }
    }

public save(): void {
        let changes = this.getChanges();
        if (!isEmpty(changes)) {
            this.onGoing = true;
            this.configService.saveConfiguration(changes)
                .subscribe(response => {
                    this.onGoing = false;
                    this.refreshAllconfig.emit();
                    // Reload bootstrap option
                    this.appConfigService.load().subscribe(() => { }
                        , error => console.error('Failed to reload bootstrap option with error: ', error));
                    this.msgHandler.showSuccess('CONFIG.SAVE_SUCCESS');
                }, error => {
                    this.onGoing = false;
                    this.msgHandler.handleError(error);
                });
        } else {
            // Inprop situation, should not come here
            console.error('Save abort because nothing changed');

public cancel(): void {
        let changes = this.getChanges();
        if (!isEmpty(changes)) {
            this.confirmMessageHandler.confirmUnsavedChanges(changes);
        } else {
            // Invalid situation, should not come here
            console.error('Nothing changed');
        }
    }

public cancel(): void {
        let changes = this.getChanges();
        if (!isEmpty(changes)) {
            this.confirmMessageHandler.confirmUnsavedChanges(changes);
        } else {
            // Invalid situation, should not come here
            console.error('Nothing changed');
        }
    }
}

public hasChanges(): boolean {
        return  !isEmpty(this.getChanges());
    }

public hasChanges(): boolean {
        return !isEmpty(this.getChanges());
    }