Ahh ok ...I think I understand now. I added the default constructor (just initializing all values to 0) and now it seems to be running. :-) Thanks for your help.
On Sun, Oct 16, 2011 at 9:43 PM, Brock Noland <[email protected]> wrote: > Hi, > > Inline.. > > On Sun, Oct 16, 2011 at 9:40 PM, Keith Thompson <[email protected] > >wrote: > > > Thanks. I went back and changed to WritableComparable instead of just > > Comparable. So, I added the readFields and write methods. I also took > > care of the typo in the constructor. :P > > > > Now I am getting this error: > > > > 11/10/16 21:34:08 INFO mapred.JobClient: Task Id : > > attempt_201110162105_0002_m_000001_1, Status : FAILED > > java.lang.RuntimeException: java.lang.NoSuchMethodException: > > edu.bing.vfi5.KeyList.<init>() > > at > > > > > org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:115) > > at > > > org.apache.hadoop.io.WritableComparator.newKey(WritableComparator.java:84) > > at > > > org.apache.hadoop.io.WritableComparator.<init>(WritableComparator.java:70) > > at > org.apache.hadoop.io.WritableComparator.get(WritableComparator.java:44) > > at > > org.apache.hadoop.mapred.JobConf.getOutputKeyComparator(JobConf.java:599) > > at > > org.apache.hadoop.mapred.MapTask$MapOutputBuffer.<init>(MapTask.java:791) > > at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:350) > > at org.apache.hadoop.mapred.MapTask.run(MapTask.java:307) > > at org.apache.hadoop.mapred.Child.main(Child.java:170) > > Caused by: java.lang.NoSuchMethodException: > edu.bing.vfi5.KeyList.<init>() > > at java.lang.Class.getConstructor0(Class.java:2706) > > at java.lang.Class.getDeclaredConstructor(Class.java:1985) > > at > > > > > org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:109) > > > > Is it saying it can't find the constructor? > > > > > Writables and by extension WritableComparables need a default Constructor. > This makes logical sense. If hadoop is going to call the readFields() > method, it needs a previously constructed object. > > Brock > -- *Keith Thompson* Graduate Research Associate, Xerox Corporation SUNY Research Foundation Dept. of Systems Science and Industrial Engineering Binghamton University work: 585-422-6587
