fixed the
fixed the bug
java.lang.NullPointerException
        at org.apache.avro.util.Utf8.<init>(Utf8.java:38)
        at
org.apache.nutch.crawl.GeneratorReducer.setup(GeneratorReducer.java:100)
        at org.apache.hadoop.mapreduce.Reducer.run(Reducer.java:174)
        at
org.apache.hadoop.mapred.ReduceTask.runNewReducer(ReduceTask.java:650)
        at org.apache.hadoop.mapred.ReduceTask.run(ReduceTask.java:418)
        at org.apache.hadoop.mapred.Child$4.run(Child.java:255)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:396)
        at
org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1149)
        at org.apache.hadoop.mapred.Child.main(Child.java:249)