Re: Run Time exception in Java Stored Procedure

From: Thomas Kyte <tkyte_at_us.oracle.com>
Date: Thu, 06 Jan 2000 07:51:21 -0500
Message-ID: <te397sg9d2ndkhqbgvap8p8qdjpj1ql71u@4ax.com>

A copy of this was sent to Anurag Minocha <anurag_at_synergy-infotech.com> (if that email address didn't require changing) On Thu, 06 Jan 2000 15:25:41 +0530, you wrote:

>Hi,
>I have written one stored procedure in java , but it is giving a run
>time exception (Null Pointer) . It only says that a null pointer
>exception has occured. How can i see the whole exception trace so that i
>can find out the problem.
>
>For exapmle while running a java application if an exception occurs the
>user can see it and based on that fix the problem.
>
>Thanks
>Anurag
>
>also reply at
>anurag_at_synergy-infotech.com

The exception stack trace is printed into a trace file on the server (in the directory specified in the USER_DUMP_DEST init.ora parameter).

Additionally, in sqlplus, you can redirect stdout (normally captured into this trace file on the server) to the screen. for example, say you have a java sp:

$ cat Hello.java
import java.lang.*;
import java.lang.Throwable;

class Hello {

static public String World() throws Throwable {

        String foo;

                foo = null;
        
                if ( foo.equals( "bar" ) );     
        
                return "Hello World";

}

}

it'll fail with NULL pointer right away... we compile it:

$ javac Hello.java

and load it:

$ loadjava -user tkyte/tkyte Hello.class

And now, we'll execute it:

$ sqlplus tkyte/tkyte

SQL*Plus: Release 8.1.5.0.0 - Production on Thu Jan 6 08:35:16 2000 (c) Copyright 1999 Oracle Corporation. All rights reserved. Connected to:
Oracle8i Enterprise Edition Release 8.1.5.0.0 - Production With the Partitioning and Java options
PL/SQL Release 8.1.5.0.0 - Production

tkyte_at_8i> set echo on

tkyte_at_8i> create or replace function HELLOWORLD return   2 varchar2 as
  3 language java name 'Hello.World() return   4 java.lang.string';
  5 /
Function created.

tkyte_at_8i> variable myString varchar2(25);

HERE we enable serveroutput and use dbms_java to tell the java runtime to put system output in the dbms_output buffer, not into the trace file...

tkyte_at_8i> set serveroutput on size 1000000 tkyte_at_8i> exec dbms_java.set_output( 1000000 )

PL/SQL procedure successfully completed.

Call the procedure... It'll fail...

tkyte_at_8i> call HelloWorld() into :myString   2 /
call HelloWorld() into :myString

     *
ERROR at line 1:
ORA-29532: Java call terminated by uncaught Java exception: java.lang.NullPointerException

Now, we would like to see the results (the stack trace). to do this, we need to successfully execute something -- null works fine for this...

tkyte_at_8i> exec null
java.lang.NullPointerException
at Hello.World(Hello.java:12)

PL/SQL procedure successfully completed.

and there is the stack trace....

--
See http://osi.oracle.com/~tkyte/ for my columns 'Digging-in to Oracle8i'... Current article is "Part I of V, Autonomous Transactions" updated June 21'st  

Thomas Kyte                   tkyte_at_us.oracle.com
Oracle Service Industries     Reston, VA   USA

Opinions are mine and do not necessarily reflect those of Oracle Corporation Received on Thu Jan 06 2000 - 06:51:21 CST