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Calling java from python

843785Feb 18 2009 — edited Feb 19 2009
Hi,

I am trying to call java methods from a python script. Jython is not an option. I have looked at using Jpype. Below is my code thus far:

Jpype.py

from jpype import *

startJVM("C:\Program Files\Java\jdk1.6.0_12\jre\bin\client", "-ea", "-Djava.class.path=%s" % classpath)
com =JPackage("CallJavaFromPython")
jp = com.Jpype1()
jp.printArgument("XXX")
shutdownJVM()

================================================== =

Jpype1.class

package CallJavaFromPython;

public class Jpype1 {

public static void main(String args[]){
System.out.println(args[0]);
}

public void printArgument(String arg){
System.out.println(arg);
}

}

================================================== =

Error message i am getting when I try to run the python script is :

NameError: name 'startJVM' is not defined


has anyone come across this before?

Thanks in advance...

Comments

Peter Gjelstrup
Answer
1. What is the difference between the below 2 index usage scenarios:
/*+ index(a index_name) parallel(a,4)*/
/*+ parallel_index(a,index_name,4)*/
Are both these same?
No,
First are two hints, one to use index and one to instruct the optimizer to use 4 concurrent servers for a parallel operation

The second is just one hint. it tells optimizer to use 4 concurrent servers on partitioned indexes.
2. What is full index scan and fast full index scan?
Full index scan do single block reads.
Fast full scan do multi block reads.

3. I have a table created in database and it has a few indexes on some columns. How can I check whether the index is Bitmap or B-Tree ?
In user_|all_dba_indexes. Index_type will be BITMAP or NORMAL

Regards
Peter


P.S: Speaking of hints. Bookmark this, can answer most of such questions much better than I can:
http://www.oracle.com/pls/db112/homepage

Edited by: Peter on Mar 26, 2013 1:47 PM
Marked as Answer by AB312062 · Sep 27 2020
AB312062
Thanks Peter !

Can you tell more about the difference in using index and parallel_index. I din't fully understand. If you could explain with some example or provide some link where I can find more information, that would be helpful.

Regards
AB
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Locked on Mar 19 2009
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