OrcStruct cannot be cloned using WritableUtils

I am trying to clone OrcStruct objects obtained from OrcInputFormat.next() method but, it fails with exception of

java.lang.RuntimeException: java.lang.NoSuchMethodException: org.apache.hadoop.hive.ql.io.orc.OrcStruct.<init>()
	at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:131)
	at org.apache.hadoop.io.WritableUtils.clone(WritableUtils.java:217)

So there is no public constructor for this Writable object. Is there any specific reason for making the constructor not accessible for a public class?