Storage may still be written to and read from concurrently

package com.fsck.k9.preferences;

import java.util.Collections;

import java.util.HashMap;

import java.util.Map;

import timber.log.Timber;

public class Storage {

    private HashMap<String, String> storage = new HashMap<>();

    private volatile Map<String, String> storage = Collections.emptyMap();

    public Storage() { }

    }

    public void replaceAll(Map<String, String> workingStorage) {

        storage.clear();

        storage.putAll(workingStorage);

        storage = new HashMap<>(workingStorage);

    }

}