package org.hisp.dhis.android.core.user;

import android.support.annotation.NonNull;

import java.util.Date;

public interface UserStore {
    long insert(
            @NonNull String uid, @NonNull String name, @NonNull String displayName,
            @NonNull Date created, @NonNull Date lastUpdated, @NonNull String birthday,
            @NonNull String education, @NonNull String gender, @NonNull String jobTitle,
            @NonNull String surname, @NonNull String firstName, @NonNull String introduction,
            @NonNull String employer, @NonNull String interests, @NonNull String languages,
            @NonNull String email, @NonNull String phoneNumber, @NonNull String nationality);

    void close();
}

package org.hisp.dhis.android.core.user;

import android.support.annotation.NonNull;
import android.support.annotation.Nullable;

import java.util.Date;

public interface UserStore {
    long insert(
            @NonNull String uid, @NonNull String name, @NonNull String displayName,
            @NonNull Date created, @NonNull Date lastUpdated,
            @Nullable String birthday, @Nullable String education, @Nullable String gender,
            @Nullable String jobTitle, @Nullable String surname, @Nullable String firstName,
            @Nullable String introduction, @Nullable String employer, @Nullable String interests,
            @Nullable String languages, @Nullable String email, @Nullable String phoneNumber,
            @Nullable String nationality);

    void close();
}

Correct @NonNull and @Nullable annotations in UserStore interface