java – Clear method implementation at Service Layer

At the Service Layer, have an interface given to me,

package com.acme.account.service;

public interface AccountService {
    void clear();

And I implement the method like this,

public class AccountServiceImpl implements AccountService {

    public AccountRepository repository;

    public void clear() {


It is worked but what could be wrong with this implementation?
What are the improvements that can implementable?
Could it be something to go bad with this code?

I appreciated if you judging my code.