@SuppressWarnings("unchecked")
    public static <T> T fieldValue(Object o, Class<?> clazz, String fieldName)  {
        try {
            Field field = clazz.getDeclaredField(fieldName);
            field.setAccessible(true);
            return (T) field.get(o);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
Assert that a future raises an expected exception cause type. Return the exception cause
if the assertion succeeds; otherwise raise AssertionError.

@param future The future to await
@param exceptionCauseClass Class of the expected exception cause
@param <T> Exception cause type parameter
@return The caught exception cause
clients/src/test/java/org/apache/kafka/test/TestUtils.java