### Question:
OAuth2TokenDAO extends AbstractSearcherDAO implements IOAuth2TokenDAO { @Override public List<OAuth2AccessToken> findTokensByUserName(String username) { return this.findTokensByClientIdAndUserName(null, username); }  @Override List<OAuth2AccessToken> findTokensByClientIdAndUserName(String clientId, String username); @Override List<OAuth2AccessToken> findTokensByUserName(String username); @Override List<OAuth2AccessToken> findTokensByClientId(String clientId); @Override void storeAccessToken(OAuth2AccessToken accessToken, OAuth2Authentication authentication); @Override OAuth2AccessToken readAccessToken(final String accessToken); @Override void removeAccessToken(final String accessToken); @Override void removeAccessTokenUsingRefreshToken(String refreshToken); @Override void deleteExpiredToken(int expirationTime); @Override OAuth2RefreshToken readRefreshToken(String tokenValue); @Override OAuth2Authentication readAuthenticationForRefreshToken(OAuth2RefreshToken refreshToken);  }### Answer:
@Test public void findTokensByUserName() throws Exception { this.executeFindTokens(null, "username"); }