How to wake-up a Java Stored Proc at Oracle Server Startup

Hi,
I am writing a Java Stored Procedure responsible to
execute periodically (daily for example) a command (the
command and its arguments are prepared by the Java stored
procedure and they are date and time sensitive).
My questions are:
1. Is there any way that my Java stored procedure is
initially NOTIFIED (woke-up) when the Oracle server is
started ? I noticed that there is a built-in Java stored procedure in Oracle DB declared as:
"PROCEDURE notify_at_startup( user_schema VARCHAR2, classname VARCHAR2) ;"
Can this be used in any way for my purpose ? If yes, how ?
2. I can do the PERIODIC scheduling of execution of the
command using standard (SUN) java timer/Thread
primitives. Are there any Oracle Java classes/methods
which can be used instead for this scheduling ?
Thanks for any help/suggestions.
Arminius

I would look at two things.
1) Create a database level trigger that fires at server start up.
2) Define an Oracle Job that runs every xx minutes and restarts itself.
Chet West

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Java Stored Proc and Oracle 8.0.6.20?

Hi,
I have a customer using Oracle 8.0.6 (on multi-platforms). We'll need to implement a pl/sql which needs to execute an external script.
My understanding is there are only 2 ways to achieve this: (a) use Java stored procedure, (b) use C/C++ library
Question 1: Is Java Stored Proc available in 8.0.6?
Question 2: Is there anywhere I can download Oracle 8.0.6 (Windows, or Tru64, Linux)?
- Will

java in the database was introduced from Oracle8i onwards. this version of Oracle does not support java virtual machine in the database.
You would need to use C/C++ external procedures.

Calling an EJB deployed in OC4J from Java Stored Proc in Oracle

Hello!
Trying to make a call to an EJB deployed in OCJ4 from a oracle java stored proc. After loaded orion.jar and crimson.jar lib into SCOTT schema, I can't get the JNDI Context working because of this error:
============================================
javax.naming.NoInitialContextException: Cannot instantiate class:
com.evermind.server.ApplicationClientInitialContextFactory. Root exception is
java.lang.ClassNotFoundException:
com/evermind/server/ApplicationClientInitialContextFactory
at java.lang.Class.forName0(Class.java)
at java.lang.Class.forName(Class.java)
at com.sun.naming.internal.VersionHelper12.loadClass(VersionHelper12.java:45)
at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java)
at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java)
at javax.naming.InitialContext.init(InitialContext.java)
at javax.naming.InitialContext.<init>(InitialContext.java)
===============================
I did load the java with "loadjava" with on time with the "resolve" option and time time no option and still no working.
Here is the EJB client code:
=======================================
import java.sql.*;
import java.util.*;
import javax.naming.*;
import com.evermind.server.ApplicationClientInitialContextFactory;
class EmpRemoteCall {
public static void main(String[] args) {
System.out.println(getEmpName());
public static String getEmpName() {
String ejbUrl = "java:comp/env/ejb/Emp";
String username = "admin";
String password = "admin";
Hashtable environment = new Hashtable();
environment.put(Context.INITIAL_CONTEXT_FACTORY, "com.evermind.server.ApplicationClientInitialContextFactory");
environment.put(Context.PROVIDER_URL, "ormi://127.0.0.1/testemp");
environment.put(Context.SECURITY_PRINCIPAL, username);
environment.put(Context.SECURITY_CREDENTIALS, password);
//environment.put(Context.SECURITY_AUTHENTICATION, ServiceCtx.NON_SSL_LOGIN);
//environment.put(javax.naming.Context.URL_PKG_PREFIXES, "oracle.aurora.jndi");
com.kboum.sertir.essais.EmpHome homeInterface = null;
try {
Class.forName("com.evermind.server.ApplicationClientInitialContextFactory", true, ClassLoader.getSystemClassLoader());
System.out.println("Creating an initial context");
Context ic = new InitialContext(environment);
System.out.println("Looking for the EJB published as 'java:comp/env/ejb/Emp'");
homeInterface = (com.kboum.sertir.essais.EmpHome) ic.lookup(ejbUrl);
catch (CommunicationException e) {
System.out.println("Unable to connect: " + ejbUrl);
e.printStackTrace();
//System.exit(1);
catch (NamingException e) {
System.out.println("Exception occurred!");
System.out.println("Cause: This may be an unknown URL, or some" +
" classes required by the EJB are missing from your classpath.");
System.out.println("Suggestion: Check the components of the URL," +
" and make sure your project includes a library containing the" +
" EJB .jar files generated by the deployment utility.");
e.printStackTrace();
//System.exit(1);
catch (ClassNotFoundException e) {
System.out.println("Unable to connect: " + ejbUrl);
e.printStackTrace();
//System.exit(1);
try {
System.out.println("Creating a new EJB instance");
com.kboum.sertir.essais.Emp remoteInterface = homeInterface.findByPrimaryKey(Integer.valueOf("7369"));
System.out.println(remoteInterface.getENAME());
System.out.println(remoteInterface.getSAL());
remoteInterface.setSAL(2);
System.out.println(remoteInterface.getSAL());
return remoteInterface.getENAME();
catch (Exception e) {
System.out.println(e.getMessage());
e.printStackTrace();
return "error";
null

What I did to solve this problem was to
create a simple RMI remote object that
resides outside the database JVM and that
serves as a proxy EJB client for your java
stored procedure. The stored procedure can
invoke a method on the remote RMI object
which then looks up the EJBean's home
interface and invokes the relevant method on
the bean's remote interface, and relays any
return values back to the java stored
procedure.
Hope this helps,
Avi.
null

How to pass a refcursor to a java stored proc

Hi all,
Please forgive me as I am new to Java and JDeveloper....
I want to pass a refcursor to a java stored proc. Does anyone know how to accomplish this?
Thanks,
dayneo

Hi,
As Avi has indicated, you can map ref cursor to java.sql.ResultSet
here are Call Specs and a code snippet from chapter 3 in my book.
procedure rcproc(rc OUT EmpCurTyp)
as language java
name 'refcur.refcurproc(java.sql.ResultSet[])';
function rcfunc return EmpCurTyp
as language java
name 'refcur.refcurfunc() returns java.sql.ResultSet';
* Function returning a REF CURSOR
public static ResultSet refcurfunc () throws SQLException
Connection conn = null;
conn = DriverManager.getConnection("jdbc:oracle:kprb:");
((OracleConnection)conn).setCreateStatementAsRefCursor(true);
Statement stmt = conn.createStatement();
((OracleStatement)stmt).setRowPrefetch(1);
ResultSet rset = stmt.executeQuery("select * from EMP order by empno");
// fetch one row
if (rset.next())
System.out.println("Ename = " + rset.getString(2));
return rset;
Kuassi

How to publish a Java Stored proc....

Hi,
I wrote the following Java code and loaded it into Oracle 8i, as Java stored procs.
public class EmployeeStruct
public int EmployeeNum;
public String EmployeeName;
public String Designation;
and
import java.sql.*;
import java.io.*;
import oracle.jdbc.driver.*;
public class InsertData
public static InsertEmployee(EmployeeStruct eps) throws SQLException
Connection conn =
DriverManager.getConnection("jdbc:default:connection:");
String sql = "INSERT INTO EMPLOYEE_TABLE VALUES (?, ?, ?)";
try
PreparedStatement pstmt = conn.prepareStatement(sql);
pstmt.setInt(1, eps.EmployeeNum);
pstmt.setString(2, eps.EmployeeName);
pstmt.setString(3, eps.Designation);
pstmt.executeUpdate();
pstmt.close();
catch (SQLException e)
System.out.println(e.getMessage());
My question is how do I publish the InsertData proc. I tried :
CREATE OR REPLACE PROCEDURE insert_data (e EMPLOYEESTRUCT) AS LANGUAGE JAVA
NAME 'INSERTDATA(EmployeeStruct)';
but this gives me PLS-00201, identifier EmployeeStruct must be declared.
COULD SOMEONE HELP ME/ SHOW ME HOW ?
I wish to call the java stored proc from an external java program.
rgds
Jeevan S
null

You can't pass Java classes to Java Stored Procedures via the PL/SQL wrapper. You'll have to write your wrapper to take the int as a NUMBER and the two Strings separately as VARCHAR2s, e.g.:
CREATE OR REPLACE PROCEDURE insert_data
EmployeeNum IN NUMBER,
EmployeeName IN VARCHAR2,
Designation IN VARCHAR2
AS LANGUAGE JAVA
NAME 'InsertData.InsertEmployee(int, java.lang.String, java.lang.String)';
John H.
null

How to pass XMLType as parameters to Java stored procs ?

How to pass XMLType as parameters to Java stored procs ?
ORA-00932: inconsistent datatypes: expected an IN argument at position 1 that is an instance of an Oracle type convertible to an instance of a user defined Java class got an Oracle type that could not be converted to a java class
Java stored proc -->
CREATE or replace FUNCTION testJavaStoredProcMerge( entity xmltype,event xmltype ) RETURN VARCHAR2 AS LANGUAGE JAVA
NAME 'XDBMergeOp.merge(org.w3c.dom.Document,org.w3c.dom.Document) return java.lang.String';
PL/SQL -->
declare
theQuote VARCHAR2(50);
entity xmltype;
event xmltype;
begin
entity := xmltype('<Quote><Fields><Field1>f1</Field1></Fields></Quote>');
event := xmltype('<Quote><Fields><Field2>f2</Field2></Fields></Quote>');
theQuote := testJavaStoredProcMerge(entity,event);
dbms_output.put_line(theQuote);
end;
Java class -->
public class XDBMergeOp {
public static String merge(Document entity, Document event) throws Exception {
return ...
Thanks in advance.

I think you'll need to use XMLType and then extract the DOM inside java..
create or replace package SAXLOADER
as
procedure LOAD(P_PARAMETERS XMLTYPE, P_DATASOURCE BFILE);
end;
create or replace package body SAXLOADER
as
procedure LOAD(P_PARAMETERS XMLTYPE, P_DATASOURCE BFILE)
AS
LANGUAGE JAVA
NAME 'com.oracle.st.xmldb.pm.saxLoader.SaxProcessor.saxLoader ( oracle.xdb.XMLType, oracle.sql.BFILE)';
end;
public static void saxLoader(XMLType parameterSettings, BFILE dataSource)
throws Exception {
    Document parameters = parameterSettings.getDocument();
    SaxProcessor app = new SaxProcessor(parameters);
    app.processXMLFile(dataSource);
Edited by: mdrake on Apr 6, 2009 11:28 AM

XML Parsing in Java Stored Proc--Oracle XML Support Installation?

I am working with a third party product that is having difficulty running a java stored proc that is parsing a supplied XML file. The proc basically looks like:
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;
InputStream is = getXMLAsInputStream(xml);
try {
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse( is );
... parse the document ....
catch (FactoryConfigurationError e) {
// unable to get a document builder factory
We are running on 9.2.0.6, HP-UX 64-bit. At first, when we would attempt to run the proc, a database hang would occur; now after attempting to install using loadjava jars for xerces2.6: ORA-29532: Java call terminated by uncaught Java exception:
javax.xml.parsers.FactoryConfigurationError: Provider
org.apache.xerces.jaxp.DocumentBuilderFactoryImpl not found)
The vendor says that the errors we are getting when running are not due to any dependency on xerces or jre1.4, and that we need to "install Oracle XML support", but I'm not certain what this means (I cannot find any documentation on what to install). I believe that there are jars that need to be loaded into the database to support the XML parsing, as jre1.3 does not include built-in XML support, and Oracle 9.2.0.6 uses jre1.3.
So...does anyone have any thoughts as to how to resolve the missing references? Is there a way to "install Oracle XML support", or is it to install the necessary jars?
Thanks,
Candi

Candi,
The following resources should be of help:
Oracle9i Database Release 2 (9.2) Documentation Library
In particular, check out the following:
Java Developer's Guide
Java Stored Procedures Developer's Guide
XML API Reference - XDK and Oracle XML DB
XML Database Developer's Guide - Oracle XML DB
XML Developer's Kits Guide - XDK
If that doesn't help, then try the following:
OracleJVM and Java Stored Procedures
XML Technology Center
Good Luck,
Avi.

Java stored proc deploy problem

I get follow error,when I deploy Java stored proc with JDeveloper3.2.
Errors:
*** Errors occurred while loading the archive into 8i JVM ***
How can i do?
Thanks a lot!!

The problem is with the OUT parameters. If you read the documentation you will see that OUT parameters
need to be declared as one element arrays. Hence this should compile:
CREATE OR REPLACE PROCEDURE TEST ( id IN NUMBER,
i IN NUMBER,
j IN VARCHAR2,
ret1 OUT NUMBER,
ret2 OUT VARCHAR2,
k IN NUMBER) AS
LANGUAGE JAVA NAME 'com.fn.oracle.proc.trading.TestProcedure.testIt(int, double, java.lang.String, int[], java.lang.String[], int)';Cheers, APC

Java Stored Proc, passing BLOB, not stored in a table.

I have checked this article, and found it will not suit my needs.
http://otn.oracle.com/sample_code/tech/java/codesnippet/jdbc/lob/LobToSP.html
I have even looked at the 4 articles on the "JSP How-To Documents" page.
I need to pass in a BLOB to my Java Stored proc, but not store it in the DB - My java code manipulates the LOB and it should never go into the DB. I know I could do the normal store, get an id and pass to my JSP... but that is a poor way to implement this. Are there any code samples on how to do this please ?
D

WOW! That seems like a very bad design.
Is it just the compiler that has the problem or is the PL/SQL code inside the stored procedure also affected? For example, if I'm doing an
EXECUTE IMMEDIATE 'insert ... INTO OtherSchema.tblTest';
Is this going to be a problem?
The problem with granting the access explicitly is the Archive Schema, which has the stored procedure that is failing, might not exist at the time when the other schemas are created. Therefore, there is no user to grant permissions to. I solved this by granting permissions to the role and when the archive user is created it is assigned that role.
This seems like the proper way to solve this problem.

Can we call a Java Stored Proc from a PL/SQL stored Proc?

Hello!
Do you know how to call a Java Stored Proc from a PL/SQL stored Proc? is it possible? Could you give me an exemple?
If yes, in that java stored proc, can we do a call to an EJB running in a remote iAS ?
Thank you!

For the java stored proc called from pl/sql, the example above that uses dynamic sql should word :
CREATE OR REPLACE PACKAGE MyPackage AS
TYPE Ref_Cursor_t IS REF CURSOR;
FUNCTION get_good_ids RETURN VARCHAR2 ;
FUNCTION get_plsql_table_A RETURN Ref_Cursor_t;
END MyPackage;
CREATE OR REPLACE PACKAGE BODY MyPackage AS
FUNCTION get_good_ids RETURN VARCHAR2
AS LANGUAGE JAVA
NAME 'MyServer.getGoodIds() return java.lang.String';
FUNCTION get_plsql_table_A RETURN Ref_Cursor_t
IS table_cursor Ref_Cursor_t;
good_ids VARCHAR2(100);
BEGIN
good_ids := get_good_ids();
OPEN table_cursor FOR 'SELECT id, name FROM TableA WHERE id IN ( ' | | good_ids | | ')';
RETURN table_cursor;
END;
END MyPackage;
public class MyServer{
public static String getGoodIds() throws SQLException {
return "1, 3, 6 ";
null

Using an existing connection in a Java Stored Proc

Hi,
I have to invoke a Java stored procedure from a PL/SQL stored proc. In the Java stored proc I open a database connection & execute some SQLs. To do this can I use the same connection that is used to invoke the PL/SQL stored proc. In other words can we use the existing PL/SQL connection within a Java stored proc that is being called by the former PL/SQL instead of creating a new connection?
Thanks in advance.
Sunitha

Ok I understood how to get the default connection from http://www.oracle.com/technology/tech/java/sqlj_jdbc/htdocs/jdbc_faq.htm#05_01
Connection conn = DriverManager.getConnection("jdbc:default:connection");However, I find that the Java stored proc is running slower in Oracle VM than invoking it from a command line Java program using thick driver from a remote machine.
Thanks anyway.
Sunitha.

Problem with java stored procs.

Is there a restriction on accessing XML documents from Java stored procs?
I have a Java program to parse XML document and return a string. If I run this program as a stand alone, the program runs fine.
I loaded the oracle xmlparser.jar into ORACLE8i db sucessfully (used -resolve option). Then I loaded my .class file with -verbose and -resolve option and I did not get any erros. I created function which return string. When I ran the function, I did not get any value bacmk.
Can I use System.out.println in java programs in ORACLE8i. If I can where can I see the output when the program runs? I not waht other mehtods I can use to debug the program running in ORACLE8i JVM.
Thank You

Hello again,
I read the documentation of 9i and found some hints about different TCP/IP socket handling of 9i and a standard JVM.
There are some parts that give hints but I couldn't find a sample code to show how to handle the differences.
Could anyone tell me how to handle the differences or give some links to sample code?
Thanks
Detlev

How may one increase JVM/Java Stored Procedure Perfomance?

Hi all,
my question: How can one increase the performance of the Oracle JVM, especially of Java Stored Procedures?
I ask this because I did some performance analysis (and was horrified :):
I have a static Java method that'll need an average 15 ms to return - when executed locally.
The same code, uploaded to an Oracle10g instance and published as Java Stored Procedure will take awful *925 ms*.
I measured both times from within the method as shown below:
public class JSProc {
public static void doSomething() {
long start = System.currentTimeMillis();
// now comes the '15 ms'-code
long time = System.currentTimeMillis() - start;
That way, I'm not including any call spec overhead, network communication or whatever into the 925 ms. All in all the above procedure call will take about 1200 to 1500 ms until it returns to the client...
The hardware: both client/server computers have the same hardware, both use the JDK provided with the latest Oracle10g release; single difference: client is Win2K, server is Linux.
I would be immensely grateful for your suggestions concerning the possibilities to increase the JVM performance...
Greetings,
Sam

As Avi suggested, subsequent calls of the procedure within the same session will reduce the execution time down to 40 ms in my testing environment.
But that doesn't change anything for the 'first call' - when I start a new client program that opens a new connection, the Java Stored Proc will again need about a second to return.
I wrote the procedure now in PL/SQL - it will return in less than 30 ms, subsequent calls will return in less than a ms. Guess what I'll use :)
I played around with the JAVA* configuration params, but, as expected, that doesn't change anything in terms of performance. According to documentation, it will only affect the amount of classes I can load into the server.
I just read that Oracle creates a new "little" JVM for every session, and I imagine that there's lot of method intercepting and things (the ominous AOP-code) to ensure transaction security.
That's why I come to the conclusion that I won't use Java Stored Procedures for classical "connect, execute, disconnect" client-server applications. It's like full braking on the freeway :)

Parse XML in a java stored proc

I am trying to parse an xml document in a java stored procedure. Just following my nose, I have developed a stored proc that works fine in development (outside the database using JRE 1.4.1) using the Xerces 2.5 parser. But, after having transferred the xerces xercesImpl.jar, xmlapis.jar, and my implementation class into oracle using loadjava when I call my stored proc the code throws an exception trying to build the document with an error like:
NoClassDef exception org.apache.xerces.jaxp.DocumentFactoryBuilderImpl
My Code looks like this:
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.xml.sax.SAXException;
InputStream is = getXMLAsInputStream(xml);
try {
DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document document = builder.parse( is );
... parse the document ....
catch (FactoryConfigurationError e) {
// unable to get a document builder factory
The exception caught is a FactoryConfigurtionError.
I'm not particularly attached to xerces, I'm really just looking for a way to parse XML inside my java stored proc, so any help to solve my problem, or an alternative suggestion will be greatly appreciated.
thanks
Dale

I looked again and sure enough the xerces implementation classes were missing. I had run a .cmd file containing these two lines, but it looks like only the first one ran...
loadjava -u ncc/xyz@usd -v -r M:\Database\JavaGeocode\Xerces2_5_0\xml-apis.jar
loadjava -u ncc/xyz@usd -v -r M:\Database\JavaGeocode\Xerces2_5_0\xercesImpl.jar
Now I've got everything working fine with Xerces!
Dale

Java stored proc status

hello.
What would trigger the change of "STATUS" from valid to invalid
for a java stored procedure (status of the PROCEDURE, not the
java class/source)?
E.g.
- loaded a java source/class
- published it with CREATE PROCEDURE ...
- the procedure inserts a row into some table X
- select* from user_objects where object_type = 'PROCEDURE'; shows that
the proc is valid
- call the proc, fine
- delete a column from the table X
- select* from user_objects where object_type = 'PROCEDURE'; shows that
the proc is still VALID
- call the proc, the call actually completed without error! (but the new row didn't get inserted into the table)
When the schema of a table that a java stored proc refers
to changes, will the java stored proc automatically marked
as "INVALID"? If not, when will this status changed from
VALID to INVALID?
Thanks.
Min

Min:
A java stored procedure is marked as VALID or INVALID depending on whether Oracle had any problems loading the class file into the database. Since you had no problems loading the class file it will always be valid.
Now, after you deleted the column in the table I would assume that the java stored procedure would have a problem when it tried to do an insert and it would throw an exception. Your java stored procedure is VALID, it just isn't executing properly and is more than likely throwing an exception.
Sometimes an exception thrown from a jsp is written to a log file instead of to the console. I suspect that this is the case in your situation. You think that the call to the jsp executed with no errors, but I bet it didn't. You will probably find the errors somewhere in the oracle\ora90\admin\mydatabase directory. Look at the latest .trc file. (Note: the path I gave to the .trc files may be different depending on what version of oracle you are using).

How to wake-up a Java Stored Proc at Oracle Server Startup

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