New to Java

Hi

I've created two types in my 11g (11.2.0.2) database, which are listed in the documentation;
http://download.oracle.com/docs/cd/E11882_01/java.112/e10587/datamap.htm#CHDCCHGG

SQL> CREATE TYPE city AS OBJECT (name VARCHAR2(20), state VARCHAR2(10));
  2  /

Type created.

SQL> 
SQL> CREATE OR REPLACE TYPE trip AS OBJECT (leave DATE, place city);
  2  /

Type created.

SQL> show user
USER is "XDB_DEV4"

I am now attempting to publish the object type using jpub.
I have set my CLASSPATH accordingly;

C:\java_test>set classpath
CLASSPATH=C:\tibco\tibrv\8.2\lib\tibrvnative.jar;C:\app\userk\product\11.2.0\dbhome_2\jdbc\lib\ojdbc5.jar;C:\app\userk\product\11.2.0\db
home_2\jdbc\lib\ojdbc6.jar;C:\app\userk\product\11.2.0\dbhome_2\jlib\jta.jar;C:\app\userk\product\11.2.0\dbhome_2\xdk\lib\xmlparserv2.ja
r;C:\app\userk\product\11.2.0\dbhome_2\RDBMS\jlib\xdb.jar;C:\app\userk\product\11.2.0\dbhome_2\RDBMS\jlib\aqapi.jar;C:\app\userk\produ
ct\11.2.0\dbhome_2\RDBMS\jlib\jmscommon.jar;C:\app\userk\product\11.2.0\dbhome_2\sqlj\lib\runtime12.jar;C:\app\userk\product\11.2.0\dbho
me_2\oc4j\sqlj\lib\translator.jar;C:\app\userk\product\11.2.0\dbhome_2\jlib\orai18n.jar

But I get the following error;

C:\java_test>jpub -u xdb_dev4/password -s TRIP:Trip
XDB_DEV4.TRIP
XDB_DEV4.CITY
java.io.IOException: Cannot run program "javac": CreateProcess error=2, The system cannot find the file specified
        at java.lang.ProcessBuilder.start(Unknown Source)
        at java.lang.Runtime.exec(Unknown Source)
        at java.lang.Runtime.exec(Unknown Source)
        at java.lang.Runtime.exec(Unknown Source)
        at sqlj.tools.Sqlj.runCompilation(Sqlj.java:1402)
        at sqlj.tools.Sqlj.statusMain(Sqlj.java:543)
        at oracle.jpub.DoitImpl.processSqlj(DoitImpl.java:832)
        at oracle.jpub.DoitImpl.mainSql(DoitImpl.java:398)
        at oracle.jpub.DoitImpl.main(DoitImpl.java:110)
        at oracle.jpub.Doit.main(Doit.java:28)
        at oracle.jpub.publish.Main.main(Main.java:9)
        at oracle.jpub.Main.main(Main.java:6)
Caused by: java.io.IOException: CreateProcess error=2, The system cannot find the file specified
        at java.lang.ProcessImpl.create(Native Method)
        at java.lang.ProcessImpl.<init>(Unknown Source)
        at java.lang.ProcessImpl.start(Unknown Source)
        ... 12 more
Error in Java compilation: Cannot run program "javac": CreateProcess error=2, The system cannot find the file specified

What do the errors mean?