### Question:
ConfigValidationException extends RuntimeException { public static ConfigValidationException createIncompatiblePairsOfTransactionsAndIDPs(Map<TransactionConfig, List<IdentityProviderConfig>> incompatibleIdps) { return new ConfigValidationException(incompatibleIdps.keySet().stream().map(transactionEntity -> MessageFormat.format( "Transaction unsupported by IDP(s).\nTransaction: {0}\nIDP(s): {1}\n", transactionEntity.getEntityId(), incompatibleIdps.get(transactionEntity).stream().map(IdentityProviderConfig::getEntityId).collect(Collectors.toList())) ).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 createIncompatiblePairsOfTransactionsAndIDPs() throws Exception { Map<TransactionConfig, List<IdentityProviderConfig>> incompatiblePairs = Map.of(aTransactionConfigData().build(), singletonList(anIdentityProviderConfigData().build())); ConfigValidationException exception = ConfigValidationException.createIncompatiblePairsOfTransactionsAndIDPs(incompatiblePairs); assertThat(exception.getMessage()).isEqualTo("Transaction unsupported by IDP(s).\n" + "Transaction: default-transaction-entity-id\n" + "IDP(s): [default-idp-entity-id]\n"); }