### Question:
Message extends StructValue { public Message reply( Type rType ) { Message rmsg = new Message( rType, vf ); rmsg.setInReplyTo( getMessageId() ); return rmsg; } Message( Type type, ValueFactory vf );  Message( Type type, ValueFactory vf, int length ); ValueFactory vf(); Message reply( Type rType ); Message reply(); Long getMessageId(); void setMessageId( Long msgid ); Long getInReplyTo(); void setInReplyTo( Long msgid );  }### Answer:
@Test public void reply() { Message msg = new Message( mt1, vf ); msg.setMessageId( 12345L ); Message rmsg = msg.reply( rmt ); assertSame( rmt, rmsg.type() ); assertSame( vf, rmsg.vf() ); assertEquals( 12345L, rmsg.getInReplyTo() ); }