Pas Apicella

JDeveloper 11g (BOXER) was released today, and if your using web services it's worth reading the release notes as follows.

http://www.oracle.com/technology/products/jdev/htdocs/11/knownissues.html#wsd

When creating a JAX-WS proxy for a external web service you may get an error as follows

Exception in thread "main" javax.xml.ws.WebServiceException: weblogic.wsee.wsdl.WsdlException: Failed to read wsdl file from url due to -- java.io.FileNotFoundException: D:\jdev11gbea\jdeveloper\jdev\mywork\WebServiceProxy\Project1\classes\SimpleWS.wsdl (The system cannot find the file specified)
at weblogic.wsee.jaxws.spi.WLSProvider.readWSDL(WLSProvider.java:306)

The easiest way to avoid this is on page 3 of 8 of the JAX-WS Proxy wizard uncheck "Copy WSDL into project"

The issue is release noted as follows.

http://www.oracle.com/technology/products/jdev/htdocs/11/knownissues.html#wsd12http://feeds.feedburner.com/TheBlasFromPas

The JVM Mbean within an OC4J 10.1.3.x container has some useful statistic which are displayed in ASC MBean browser. Here is some code which shows how to obtain those from a JMX client.

So the MBean we want to access is as follows:

oc4j:j2eeType=JVM,name=single,J2EEServer=standalone

And the statistics we want to display which ASC shows for us are as follows:

• FreeHeapSize
• ActiveThreads
• HeapSize

So here is the code we will use from a JMX Client. The method which obtains the statistics we need is called "showStats(ObjectName)"

package oracle.support.oc4j.standalone;

import java.text.DateFormat;

import java.util.Date;
import java.util.logging.Logger;

import javax.management.MBeanServerConnection;
import javax.management.ObjectName;
import javax.management.j2ee.statistics.JVMStats;
import javax.management.j2ee.statistics.Statistic;
import javax.management.j2ee.statistics.BoundedRangeStatistic;

public class JVMMonitor implements Runnable
{
 private final Logger logger = Logger.getLogger(this.getClass().getName());
 private static final DateFormat DATEFORMAT = DateFormat.getInstance();
 private OC4JConnection con = null;
 private MBeanServerConnection mbs = null;
 private String targetMBean = "oc4j:j2eeType=JVM,name=single,J2EEServer=standalone";
 private ObjectName mbean = null;

 public JVMMonitor() throws Exception
 {
   // retrieve an OC4JConnection object this is a singleton class
   con = OC4JConnection.getInstance();
   mbs = con.getConnection();
   mbean = new ObjectName(targetMBean);
   System.out.println("** JVM Details **");
   System.out.printf("Opmn Managed:  %s\n",
       mbs.getAttribute(mbean, "opmnEnabled")); 
   System.out.printf("Java Version:  %s\n",
       mbs.getAttribute(mbean, "javaVersion"));
   System.out.printf("Java Vendor:   %s\n",
       mbs.getAttribute(mbean, "javaVendor"));
   System.out.printf("Host Node:     %s\n",
       mbs.getAttribute(mbean, "node"));
   System.out.printf("RMI Port:      %s\n",
       mbs.getAttribute(mbean, "rmiPort"));
   System.out.printf("RMIS Port:     %s\n",
       mbs.getAttribute(mbean, "rmisPort"));
   System.out.printf("RMI IP:     %s\n",
       mbs.getAttribute(mbean, "rmiServerAddress"));
     
 }

 public void run ()
 {

   System.out.println("\n");
   try
   {
     System.out.printf("--> Current JVM Details [%s]\n\n",
                       DATEFORMAT.format(new Date())); 

  
     showStats(mbean);
     System.out.printf("\n<-- End...\n");
   }
   catch (Exception e)
   {
     System.out.println("Error in run()");
     e.printStackTrace();
   }
   finally
   {
     //con.close();
   }
 }

 private void showStats(ObjectName cp) throws Exception
 {

   JVMStats stats =
     (JVMStats) mbs.getAttribute(cp, "stats");

   Object mem = null;
   mem = mbs.getAttribute(cp, "totalMemory");
   Long  memLong = null;
   memLong = (Long) mem;

   System.out.printf("Total Memory:  %s\n", memLong.intValue()/1024/1024 + "M");
 
   mem = mbs.getAttribute(cp, "freeMemory");
   memLong = (Long) mem;
   System.out.printf("Free Memory:  %s\n",
     memLong.intValue()/1024/1024 + "M");
 
   System.out.printf("HeapSize:  %s\n",
     stats.getHeapSize().getCurrent()/1024 + "M");
   System.out.printf("HighWaterMark:  %s\n",
     stats.getHeapSize().getHighWaterMark()/1024 + "M");
   System.out.printf("LowWaterMark:  %s\n",
     stats.getHeapSize().getLowWaterMark()/1024 + "M");
 
   Statistic[] allStats = stats.getStatistics();

   for (Statistic s: allStats)
   {
     if (!s.getName().equalsIgnoreCase("UpTime"))
     {
       System.out.println("\n--");
       System.out.printf("JVM Statistic [%s]\n", s.getName());
       System.out.printf("Description      : %s\n", s.getDescription());
       System.out.printf("Unit             : %s\n", s.getUnit());
       System.out.printf("Last Sample Time : %s\n", new Date(s.getLastSampleTime()));
     
       BoundedRangeStatistic brs = (BoundedRangeStatistic) s;
     
       if (s.getUnit().equals("THREADS"))
       {
         System.out.printf("High WaterMark   : %s\n", brs.getHighWaterMark());
         System.out.printf("Low WaterMark    : %s\n", brs.getLowWaterMark());
         System.out.printf("Current          : %s\n", brs.getCurrent());
       }
       else
       {
         System.out.printf("High WaterMark   : %s\n", brs.getHighWaterMark()/1024 + "M");
         System.out.printf("Low WaterMark    : %s\n", brs.getLowWaterMark()/1024 + "M");
         System.out.printf("Current          : %s\n", brs.getCurrent()/1024 + "M");      
       }
   
     }
   }
 

 }

}

So the output would then be as follows:

** JVM Details **
Opmn Managed: true
Java Version: 1.5.0_06
Java Vendor: Sun Microsystems Inc.
Host Node: beast.au.oracle.com
RMI Port: 12406
RMIS Port: 12706
RMI IP: 10.187.80.70

JVMMonitor
Period to report results in seconds is : 5

** Started [4/09/08 11:29] with 5(sec) interval between reports **


--> Current JVM Details [4/09/08 11:29]

Total Memory: 515M
Free Memory: 453M
HeapSize: 515M
HighWaterMark: 550M
LowWaterMark: 504M

--
JVM Statistic [FreeHeapSize]
Description : The amount of free heap memory
Unit : KILO BYTES
Last Sample Time : Thu Sep 04 11:06:44 EST 2008
High WaterMark : 515M
Low WaterMark : 433M
Current : 453M

--
JVM Statistic [ActiveThreads]
Description : The number of active thread(s)
Unit : THREADS
Last Sample Time : Thu Sep 04 11:06:44 EST 2008
High WaterMark : 64
Low WaterMark : 4
Current : 64

--
JVM Statistic [HeapSize]
Description : The size of the JVM's heap
Unit : KILO BYTES
Last Sample Time : Thu Sep 04 11:06:44 EST 2008
High WaterMark : 550M
Low WaterMark : 504M
Current : 515M

<-- End...

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If you ever try to do a "desc emp" from a JDBC program , that won't work as that's a SQL*Plus command only, but here is how to write an SQL statement to do that which can easily be converted into a JDBC program and used.

Firstly here is what we get when we describe the EMP table in SQL*Plus.

SCOTT@linux10g> desc emp;
 Name                                Null?    Type
 ----------------------------------- -------- ------------------------
 EMPNO                               NOT NULL NUMBER(4)
 ENAME                                        VARCHAR2(10)
 JOB                                          VARCHAR2(9)
 MGR                                          NUMBER(4)
 HIREDATE                                     DATE
 SAL                                          NUMBER(7,2)
 COMM                                         NUMBER(7,2)
 DEPTNO                                       NUMBER(2)

Now here is the SQL we can use to get the same output from an SQL query.

select
 column_name as "Name",
 decode(NULLABLE, 'Y', '', 'N', 'Not Null') as "Null",
 data_type||decode(data_type,
 'NUMBER', decode(DATA_PRECISION, NULL, '',
 '('||DATA_PRECISION||','||data_scale||')'),
 'VARCHAR2', '('||data_length||')',
 'CHAR', '('||data_length||')') as "Type"
from user_tab_columns
where table_name = 'EMP'

The output of that is as follows from the query above , identical to a "desc emp", or close enough, couple more decodes will sort out a few minors issues , but seems to work for most tables I tested it against.

Name                           Null     Type
------------------------------ -------- ------------------------------
EMPNO                          Not Null NUMBER(4,0)
ENAME                                   VARCHAR2(10)
JOB                                     VARCHAR2(9)
MGR                                     NUMBER(4,0)
HIREDATE                                DATE
SAL                                     NUMBER(7,2)
COMM                                    NUMBER(7,2)
DEPTNO                                  NUMBER(2,0)

So with a bind variable defined it would simply be as follows

select
 column_name as "Name",
 decode(NULLABLE, 'Y', '', 'N', 'Not Null') as "Null",
 data_type||decode(data_type,
 'NUMBER', decode(DATA_PRECISION, NULL, '',
 '('||DATA_PRECISION||','||data_scale||')'),
 'VARCHAR2', '('||data_length||')',
 'CHAR', '('||data_length||')') as "Type"
from user_tab_columns
where table_name = ?

And then easily be integrated into a JDBC program, I did this over the web using a JSP page, which lists all user tables and adds a DESCRIBE button next to the table name to get the output above when clicked.http://feeds.feedburner.com/TheBlasFromPas

Recently I was asked how to determine if any current HTTP sessions exist for an application. The reason for needing this information was so that the application could be redeployed only when no HTTP sessions existed and the application was currently not being used. It turns out there is an MBean which can give you that information.

The Mbean is as follows:

oc4j:j2eeType=ClassLoading,name=singleton,J2EEServer=standalone
His how to access it from the MBean browser in ASC and get the information on HTTP sessions for your deployed applications.

1. Log into ASC
2. Click on the container you wish to use.
3. Click on the link "Administration".
4. Click on the "Go To Task" icon as follows.

JMX -> System MBean Browser

5. Expand the ClassLoading node in the navigation pane, then select the singleton MBean instance.
6. Click the Operations tab in the right-hand pane, then click the executeQuery operation.

Three versions of the executeQuery operation are exposed. Click the version that takes one parameter.

7. For the value parameter enter in the following and press the "Invoke Operation" button

HttpSessions(details)

You will end up with output as follows which will give you the amount of HTTP sessions which currently exist for each deployed application.

** Summary at Aug 11, 2008 9:57:43 AM **

Total Sessions: 0
Total Attributes: 0
Total Session Size: 0 bytes

Largest Session: N/A
Youngest Session: N/A
Idlest Session: N/A
Oldest Session: N/A

** Details **

[ADFBC-HA:adfhaprofile]

No active sessions

[SimpleWS:WebServices]

No active sessions

[WebServiceDemo-SimpleWS-WS:WebServices]

No active sessions

...
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In order for remote clients to access a OAS 10.1.3.x JNDI Server-Side context they must authenticate with the server prior to doing a look up. Here is how to enable such access from a remote J2SE client and what setup steps are required to achieve this for deployed applications, thus avoiding using privileged users such as oc4jadmin.

This example is based on JAZN-XML security provider at the instance level.

1. Log into Application Server Console (ASC).
2. Click on your container you wish to use.
3. Click on administration link.
4. Click on the icon for the security task with a description as follows -> "Configure security providers, create/delete/view users and roles".

Here we will just use "Instance" level security which will enable this user we create to be used by all applications within this instance.

5. Click on the button "Instance Level Security".
6. Click on the link "Realms".
7. You will see a column called "Users" which will have an amount of users, simple click on the amount to go to the next screen.
8. Click on the "Create" button.
9. Enter the following.

Name - test
Password - test123
Confirm Password - test123
Shuttle Across "users" to the "Selected Roles" Area

Note: You can create your own role but you must make sure you set the check box "Grant RMI Login Permission". We are using the "users" role as that has been done already for us.

10. Press OK.

So the user we want to use will be "test" with a password as "test123", with this in place we now must grant access to the JNDI context to the correct group so that remote users which are part of this group can access the JNDI resource. This is done as shown below within a deployment descriptor for each deployed application which contains JNDI objects such as a Data Source or an EJB. The file is placed within a META-INF directory of an EAR file.

orion-application.xml

<?xml version = '1.0' encoding = 'windows-1252'?>
<orion-application xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://xmlns.oracle.com/oracleas/schema/orion-application-10_0.xsd">
  <namespace-access>
    <read-access>
      <namespace-resource root="">
        <security-role-mapping>
          <group name="users" />
        </security-role-mapping>
      </namespace-resource>
    </read-access>
    <write-access>
      <namespace-resource root="">
        <security-role-mapping>
          <group name="users" />
        </security-role-mapping>
      </namespace-resource>
    </write-access>
  </namespace-access>
</orion-application>

As you can see the namespace-access has been setup to allow users which are part of the role "users" access to the JNDI Server-Side context for the deployed application.

So with a deployment descriptor added to my application named "pastest" and deployed, I can then perform a JNDI look up of resources within that application as the user "test" as shown below.

private Context getInitialContext() throws NamingException
{
Hashtable env = new Hashtable();
// Standalone OC4J connection details
env.put( Context.INITIAL_CONTEXT_FACTORY,
"oracle.j2ee.rmi.RMIInitialContextFactory" );
env.put( Context.SECURITY_PRINCIPAL, "test" );
env.put( Context.SECURITY_CREDENTIALS, "test123" );
env.put(Context.PROVIDER_URL, "ormi://localhost:23791/pastest");
return new InitialContext( env );
}

For more information see the documentation below.

Oracle® Containers for J2EE Security Guide
10g (10.1.3.1.0)
Part Number B28957-01
http://download.oracle.com/docs/cd/B31017_01/web.1013/b28957/loginmod.htm#BABIICGChttp://feeds.feedburner.com/TheBlasFromPas

If you have JDeveloper 10.1.3.x on your file system you can take advantage of 2 JAR files even without actually using the IDE. There useful utilities if your using OAS 10.1.3.x. Those are as follows.

$JDEV_HOME\j2ee\home\admin_client.jar - OC4J provides a command-line utility, admin_client.jar, for performing configuration, administration, and deployment tasks on active OC4J instances in an Oracle Application Server clustered environment as well as on a standalone OC4J server. In addition, you can use admin_client.jar to restart or stop an OC4J instance or group of instances. See this document for more details.

Oracle® Containers for J2EE Configuration and Administration Guide
10g (10.1.3.1.0)
Part Number B28950-01
http://download-uk.oracle.com/docs/cd/B31017_01/web.1013/b28950/adminclient.htm#BABCCJEC

$JDEV_HOME\webservices\lib\wsa.jar - The WebServicesAssembler tool assists in assembling Oracle Application Server Web Services. It enables you to generate the artifacts required to develop and deploy Web services, regardless of whether you are creating the service top down or bottom up. The WebServicesAssembler can also be invoked to create Web service client objects based on a WSDL. See this document for more details.

Oracle® Application Server Web Services Developer's Guide
10g (10.1.3.1.0)
Part Number B28974-01
http://download-uk.oracle.com/docs/cd/B31017_01/web.1013/b28974/wsassemble.htm#CHDDBCCA

For both of these utilties use the -help option for more details of what command line options can be used.

Eg:

java -jar D:\jdev\jdevprod\10133\webservices\lib\wsa.jar -help

Note: Stand Alone OC4J has the same JAR files as well.http://feeds.feedburner.com/TheBlasFromPas

Recently I tried to use the COLLECT function from 10g as follows from SQL*Plus which worked fine.

SQL> select COLLECT(ename) as emps from emp;

EMPS
--------------------------------------------------------------------------------
SYSTPUJ7P3Tw/Wq/gQLsKRlBJ8Q==('SMITH', 'ALLEN', 'WARD', 'JONES', 'MARTIN', 'BLAK
E', 'CLARK', 'SCOTT', 'KING', 'TURNER', 'ADAMS', 'JAMES', 'FORD', 'MILLER')

I then decided to use the same query in JDBC and got this error when trying to execute a query from a Statement object.

java.sql.SQLException: ORA-00932: inconsistent datatypes: expected NUMBER got -

It's obvious the return type needs to be something which the JDBC client can actually work with , so to get this to work I simply did this.

1. Create a TYPE to hold my array of Employee names.

CREATE OR REPLACE TYPE varchar2_enames AS TABLE OF VARCHAR2(50);

I then quickly ran a new query to ensure my TYPE was working correctly as shown below.

SQL> select CAST(COLLECT(ename) AS varchar2_enames) AS emps from emp;

EMPS
--------------------------------------------------------------------------------
VARCHAR2_ENAMES('SMITH', 'ALLEN', 'WARD', 'JONES', 'MARTIN', 'BLAKE', 'CLARK', '
SCOTT', 'KING', 'TURNER', 'ADAMS', 'JAMES', 'FORD', 'MILLER')

Note: You will se this time the return output is a table of varchar's which we can easily map to a JDBC array which we can then obtain without any errors.

2. JDBC code as follows, using the 10.2.0.4 JDBC driver

package pas.au;

import java.sql.*;
import oracle.jdbc.OracleDriver;

public class Test
{
  public Test()
  {
  }

  public void run ()
  {
    Connection conn = null;
    Statement stmt = null;
    ResultSet rset = null;
   
    String queryStr = "select CAST(COLLECT(ename) AS varchar2_enames) AS emps from emp";
 
    try
    {
      conn = getConnection();
      driverDeatils(conn);
      stmt = conn.createStatement();
      rset = stmt.executeQuery(queryStr);
      // only expecting one row
      rset.next();

      Array arr = rset.getArray(1);
      String[] values = (String[])arr.getArray();
      for( int i = 0; i < values.length; i++ )
        System.out.println( "row " + i + " = '" + values[i] +"'" );

    }
    catch (SQLException e)
    {
      e.printStackTrace();
    }
    finally
    {
      try
      {
        if (conn != null)
          conn.close();
       
        if (stmt != null)
          stmt.close();
         
        if (rset != null)
          rset.close();
      }
      catch (Exception e)
      {
        // bad luck
      }
    }
   
  }
 
  public void driverDeatils (Connection conn) throws SQLException
  {
    DatabaseMetaData dmd = conn.getMetaData();
    System.out.println("DriverVersion:      ["+
                         dmd.getDriverVersion()+"]");
    System.out.println("DriverMajorVersion: ["+
                         dmd.getDriverMajorVersion()+"]");
    System.out.println("DriverMinorVersion: ["+
                         dmd.getDriverMinorVersion()+"]");
    System.out.println("DriverName:         ["+
                         dmd.getDriverName()+"]");
  }
 
  public static Connection getConnection() throws SQLException
  {
    String username = "scott";
    String password = "tiger";
    String thinConn = "jdbc:oracle:thin:@beast:1522:linux10g";
    DriverManager.registerDriver(new OracleDriver());
    Connection conn = DriverManager.getConnection(thinConn,username,password);
    conn.setAutoCommit(false);
    return conn;
  }
 
  public static void main(String[] args)
  {
    Test test = new Test();
    test.run();
  }
}

3. Output as follows.

DriverVersion: [10.2.0.4.0]
DriverMajorVersion: [10]
DriverMinorVersion: [2]
DriverName: [Oracle JDBC driver]
row 0 = 'SMITH'
row 1 = 'ALLEN'
row 2 = 'WARD'
row 3 = 'JONES'
row 4 = 'MARTIN'
row 5 = 'BLAKE'
row 6 = 'CLARK'
row 7 = 'SCOTT'
row 8 = 'KING'
row 9 = 'TURNER'
row 10 = 'ADAMS'
row 11 = 'JAMES'
row 12 = 'FORD'
row 13 = 'MILLER'http://feeds.feedburner.com/TheBlasFromPas

If you read the 10.2 JDBC developer guide you will find that you will find you can subscribe remotely to ONS within the driver itself without the need for an oracle client.

http://download.oracle.com/docs/cd/B19306_01/java.102/b14355/fstconfo.htm#CHDCHAGH
Remote ONS Subscription

OAS 10.1.3.x ships with the 10.1.0.5 JDBC driver, so is it right to assume it doesn't support FCF out of the box?

After a recent customer visit they swapped out to the 10.2.0.4 JDBC driver as they assumed 10.1.0.5 was not supported and would not work.

That is not true in actual fact 10.1.0.5 does work and the ONS subscription occurs within opmn.xml. However if you try to use the 10.1.0.5 driver outside of OAS in a stand alone client then it won't work as you can't subscribe to ONS with that driver outside of OAS 10.1.3.x.

It is all explained here.

http://www.oracle.com/technology/products/ias/hi_av/OracleApplicationServer10gFCF.pdfhttp://feeds.feedburner.com/TheBlasFromPas

If you read the 10.2 JDBC developer guide you will find that you will find you can subscribe remotely to ONS within the driver itself without the need for an oracle client.

http://download.oracle.com/docs/cd/B19306_01/java.102/b14355/fstconfo.htm#CHDCHAGH
Remote ONS Subscription

OAS 10.1.3.x ships with the 10.1.0.5 JDBC driver, so is it right to assume it doesn't support FCF out of the box?

After a recent customer visit they swapped out to the 10.2.0.4 JDBC driver as they assumed 10.1.0.5 was not supported and would not work.

That is not true in actual fact 10.1.0.5 does work and the ONS subscription occurs within opmn.xml. However if you try to use the 10.1.0.5 driver outside of OAS in a stand alone client then it won't
work as you can't subscribe to ONS with that driver outside of OAS 10.1.3.x.

It is all explained here.

http://www.oracle.com/technology/products/ias/hi_av/OracleApplicationServer10gFCF.pdfhttp://feeds.feedburner.com/TheBlasFromPas