private String getViolationInvalidValue(final Object invalidValue) {
        if (invalidValue == null) {
            return null;
        }

        if (invalidValue.getClass().isArray()) {
            if (invalidValue instanceof Object[]) {
                // not helpful to return object array, skip it.
                return null;
            } else if (invalidValue instanceof boolean[]) {
                return Arrays.toString((boolean[]) invalidValue);
            } else if (invalidValue instanceof byte[]) {
                return Arrays.toString((byte[]) invalidValue);
            } else if (invalidValue instanceof char[]) {
                return Arrays.toString((char[]) invalidValue);
            } else if (invalidValue instanceof double[]) {
                return Arrays.toString((double[]) invalidValue);
            } else if (invalidValue instanceof float[]) {
                return Arrays.toString((float[]) invalidValue);
            } else if (invalidValue instanceof int[]) {
                return Arrays.toString((int[]) invalidValue);
            } else if (invalidValue instanceof long[]) {
                return Arrays.toString((long[]) invalidValue);
            } else if (invalidValue instanceof short[]) {
                return Arrays.toString((short[]) invalidValue);
            }
        }

        // It is only helpful to return invalid value of primitive types
        if (invalidValue.getClass().getName().startsWith("java.lang.")) {
            return invalidValue.toString();
        }

        return null;
    }
This class converts Hibernate {@link ValidationException} into http response.
rest/src/main/java/com/netflix/conductor/rest/controllers/ValidationExceptionMapper.java