### Question:
ConfigValidationException extends RuntimeException { public static ConfigValidationException createTransactionsRequireUnsupportedLevelOfAssurance(Collection<TransactionConfig> badTransactionConfigs) { return new ConfigValidationException(badTransactionConfigs.stream() .map(entityData -> MessageFormat.format( "Unsupported level of assurance in transaction config.\nEntity Id: {0}\nLevels of assurance: {1}\n", entityData.getEntityId(), entityData.getLevelsOfAssurance())) .collect(Collectors.joining("\n"))); } private  ConfigValidationException(String message); static ConfigValidationException createFileReadError(String filePath); static ConfigValidationException createDuplicateEntityIdException(String entityId); static ConfigValidationException createMissingMatchingEntityIdException(String transactionEntityId); static ConfigValidationException createAbsentMatchingServiceConfigException(String matchingServiceEntityId, String transactionEntityId); static ConfigValidationException createAbsentOnboardingTransactionConfigException(String transactionEntityId, String idpEntityId); static ConfigValidationException createInvalidCertificatesException(List<InvalidCertificateDto> invalidCertificates); static ConfigValidationException createIDPLevelsOfAssuranceUnsupportedException(Collection<IdentityProviderConfig> badIDPConfigs); static ConfigValidationException createTransactionsRequireUnsupportedLevelOfAssurance(Collection<TransactionConfig> badTransactionConfigs); static ConfigValidationException createIncompatiblePairsOfTransactionsAndIDPs(Map<TransactionConfig, List<IdentityProviderConfig>> incompatibleIdps);  }### Answer:
@Test public void createTransactionsRequireUnsupportedLevelOfAssurance() throws Exception { ConfigValidationException exception = ConfigValidationException.createTransactionsRequireUnsupportedLevelOfAssurance(singletonList(aTransactionConfigData().build())); assertThat(exception.getMessage()).isEqualTo("Unsupported level of assurance in transaction config.\n" + "Entity Id: default-transaction-entity-id\n" + "Levels of assurance: [LEVEL_1, LEVEL_2]\n"); }