Technical Jig

Mule 2.x Start Error

noreply@blogger.com (Jig) — Tue, 29 Sep 2009 21:12:00 +0000

Message:

Root Exception stack trace:

oracle.xml.parser.schema.XSDException: Duplicated definition for: 'identifiedType'

at oracle.xml.parser.v2.XMLError.flushErrorHandler(XMLError.java:418)

at oracle.xml.parser.v2.XMLError.flushErrors1(XMLError.java:284)

Solution:

The Mule 2.x app does not contain the correct Spring library. Please include the spring-context-2.5.jar

Always go to the Source

noreply@blogger.com (Jig) — Thu, 20 Aug 2009 21:54:00 +0000

Java Performance Diagnosis Tools

noreply@blogger.com (Jig) — Wed, 29 Jul 2009 21:32:00 +0000

prstat / prstat -mLp

the last number of each column is the NLWP (number light weight processes aka threads) that are currently active.
prstat -mLp will show the current threads for one process. The last column is the LWPID (light weight process ID)
LWPID’s increment by one, hence the highest LWPID indicates how many threads have been launched since process creation.

ps -fLp

indicates how many threads have been launched since process creation.

truss -f -p /

new system calls for one thread

/usr/jdk/jdk1.6.0_10/bin/jstatd -J-Djava.security.policy=jstatd.all.policy -p 52074

starts an rmi server on the local host to be able to monitor application running on this host

/usr/jdk/jdk1.6.0_10/bin/jps -q

determines the running java processes

References:

http://prefetch.net/blog/index.php/2008/01/16/monitoring-garbage-collection-with-jstat/

Curl Command

noreply@blogger.com (Jig) — Wed, 29 Jul 2009 14:32:00 +0000

curl -x (proxy.host):(proxy.port) http://www.google.com

Heap Dump

noreply@blogger.com (Jig) — Thu, 21 May 2009 16:52:00 +0000

jmap -dump:format=b,file=heap.bin 518

Mule 1.x: Spring Integration

noreply@blogger.com (Jig) — Wed, 11 Feb 2009 20:06:00 +0000

Integrating a Spring configuration file into a Mule configuration has been the most frustrating thing in the world... well at least for me.

Mule provides documentation for using Spring with Mule 1.x in the following URL:
http://www.mulesource.org/display/MULEUSER/Using+Spring+as+a+Component+Factory

However, after following these instructions, there are a couple of things that were left undocumented for the spring application context xml to be integrated successfully. The following are these undocumented notes:

The Spring application context xml file should not include a XML schema definition. It should specify the Mule-specific DTD.

Example Spring XML:

<beans xmlns="http://www.springframework.org/schema/beans" xsi="http://www.w3.org/2001/XMLSchema-instance" schemalocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

......
</beans>

In order for the Spring XML file to be read successfully by the Mule Server, the above Spring XML file must modified to use the DTD file, and not the XML Schema as follows:

<!DOCTYPE beans PUBLIC "-//MuleSource //DTD mule-configuration XML V1.0//EN"
"http://mule.mulesource.org/dtds/spring-beans.dtd">
<beans>
.......
</beans>

If you do not do this, the Mule server will throw the following exception and cause you frustration beyond belief (jk):

nested exception is org.xml.sax.SAXParseException: : XML-20149: (Error) Element 'beans' used but not declared.
When specifying the <contianer-context> element, remember to define it at the appropriate place in the mule configuration xml.
```
<!ELEMENT mule-configuration (description?,environment-properties?,mule-environment-properties?,container-context*,security-manager?,
transaction-manager?,agents?,connector*,endpoint-identifiers?,transformers?,global-endpoints?,
         interceptor-stack*,model*)
```
From the above DTD element, the container-context element should be after the mule-environment-properties element and before any connector, transformer, and model elements.

If this is not the case, the Mule Server will throw the following exception:

SAXParseException: : XML-20148: (Error) Invalid element 'container-context' in content of 'mule-configuration', expected elements '[connector, endpoint-identifiers, transformers, global-endpoints, interceptor-stack, model]'.

It will indicate the mule-configuration DTD element that does not even contain the container-context element, which may be quite confusing.

So, it seems most of these are related to DTD and XML schema definitions.

Esper

noreply@blogger.com (Jig) — Fri, 23 Jan 2009 21:54:00 +0000

Oracle SQL: Calculating on a Running Window

noreply@blogger.com (Jig) — Mon, 05 Jan 2009 16:10:00 +0000

select t1me, m1n, m1n_1, m1n_2, m1n_3, m1n_4, m1n+m1n_1+m1n_2+m1n_3+m1n_4 fiveminspan from
(select
trunc(record_timestamp,'MI') t1me,
count(*),
LEAD(count(*), 0, -1) OVER (ORDER BY trunc(record_timestamp,'MI') ASC) m1n,
LEAD(count(*), 1, -1) OVER (ORDER BY trunc(record_timestamp,'MI') ASC) m1n_1,
LEAD(count(*), 2, -1) OVER (ORDER BY trunc(record_timestamp,'MI') ASC) m1n_2,
LEAD(count(*), 3, -1) OVER (ORDER BY trunc(record_timestamp,'MI') ASC) m1n_3,
LEAD(count(*), 4, -1) OVER (ORDER BY trunc(record_timestamp,'MI') ASC) m1n_4
from REP_OWNER.BAM_MEDIA_REPORT where
record_timestamp > TO_DATE('03/30/2008', 'MM/DD/YYYY') and
record_timestamp < TO_DATE('09/29/2008', 'MM/DD/YYYY')
group by trunc(record_timestamp,'MI')
order by count(*) desc)

Lesson of the Day: Data Integrity

noreply@blogger.com (Jig) — Wed, 30 Jul 2008 21:48:00 +0000

Often, one needs to make sure that the data of one service/application is not inappropriately saved/cached in another service/application. This ensures the integrity of the data.

A single service/application may be responsible for providing a particular type of data. This data should not be cached or saved in another application. In this way, all data of this type is solely accessed from this application/service. All applications/services requesting this data would have to always retrieve it from this single service/application. Typically, however, other applications/services may reference data within this single application with an identifier or id which can be used and passed to the single service to access the actual original data. Therefore, data the actual data would not be replicated by the other services/application.

If the actual data were to be saved/cached in another application/service in order that the original service does not have to be called and thus improve performance, data integrity cannot be ensured. The data would then inadvertently be saved in two locations. If the data needs to change, one would have to update these two locations to ensure the integrity of the data.

This is a basic notion of application design.

Therefore, one needs to be careful in caching actual data that can be accessed from another service as opposed to simply saving the reference to the data which can be used for accessing the data in the originating service/application.

Database Views

noreply@blogger.com (Jig) — Wed, 21 May 2008 14:31:00 +0000

Views should be created if a query is required for accessing data from multiple tables and multiple rows of multiple tables.

CORE3282: Crash occurred in function

noreply@blogger.com (Jig) — Thu, 01 May 2008 15:10:00 +0000

[01/May/2008:11:05:23] fine ( 6208): Successfully initialized web application environment for virtual server [https-bamws]
[01/May/2008:11:05:35] info ( 6208): CORE3282: stdout: WebappClassLoader: Additional JARs have been added : 'hibernate-3.2.3.jar'
[01/May/2008:11:05:39] info ( 6208): WEB2798: [] ServletContext.log(): WEB3945: Scratch dir for the JSP engine is: /opt/sunone/https-mtan/ClassCache/https-bamws/default-webapp
[01/May/2008:11:05:39] info ( 6208): WEB2798: [] ServletContext.log(): WEB3947: IMPORTANT: Do not modify the generated servlets
[01/May/2008:11:05:44] catastrophe ( 6208): CORE3260: Server crash detected (signal SIGSEGV)
[01/May/2008:11:05:44] info ( 6208): CORE3262: Crash occurred in function pblock*NVPairs::dup()const from module /opt/sunone/bin/https/lib/libns-httpd40.so

Scenario:

I removed all jars from WEB-INF/lib with rm -r *, populated it with a new lib directory, restarted the server and the above error occurred. Restarting the server every time still caused this same error.

I tried to remove all references to this web app in the server.xml file, but the error still occurred.

Cause:

This could have been possibly caused by the removal of jars that while the server was still running. Perhaps, an artifact of the jar remained after subsequent restarts and would continuously cause the crash on the server.

Solution:

I removed the hibernate-3.2.3.jar from this lib directory and the web server now starts without error.

NoSuchMethodError: javax.xml.parsers.DocumnentBuilderFactory.getSchema()

noreply@blogger.com (Jig) — Mon, 28 Apr 2008 16:37:00 +0000

java.lang.NoSuchMethodError: javax.xml.parsers.DocumentBuilderFactory.getSchema()Ljavax/xml/validation/Schema;
at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl.newDocumentBuilder(Unknown Source)

Cause: You are using a different version of the DocumentBuilderFactory class

Solution:

This version of the javax.xml.parsers.DocumentBuilderFactory is used by the xercesImpl.jar and is defined in the jaxp-api.jar

This class is defined in the following jars:
xml-apis.jar
xmlParserAPIs.jar
xercesImpl-2.8.1.jar
jaxp-api.jar

In addition, this class is also include in the JVM. The JVM implementation of this class does not define a getSchema() method.

The only jar that contains an implementation of the DocmentBuilderFactory with the getSchema() method defined is the jaxp-api.jar. In order for this implementation to be used instead of the JVM's implementation or the other jar's implementation, you must either endorse this jar or put this jaxp-api.jar at the top of the classpath.

NoClassDefFoundError: com/sun/org/apache/xerces/internal/dom/DocumentImpl

noreply@blogger.com (Jig) — Mon, 28 Apr 2008 15:20:00 +0000

java.lang.NoClassDefFoundError: com/sun/org/apache/xerces/internal/dom/DocumentImpl
at java.lang.ClassLoader.defineClass0(Native Method)
..........
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:302)
at com.sun.xml.messaging.saaj.soap.SOAPPartImpl.(SOAPPartImpl.java:63)
at com.sun.xml.messaging.saaj.soap.ver1_1.SOAPPart1_1Impl.(SOAPPart1_1Impl.java:29)
at com.sun.xml.messaging.saaj.soap.ver1_1.Message1_1Impl.getSOAPPart(Message1_1Impl.java:52)
at

Cause: Missing a class
Solution:
There are two versions of the xercesImpl.jar that define the different classes in different packages. These packages are the following:

com.sun.org.apache
org.apache

The DocumentImpl class is defined in the following packages of each corresponding jar:
com.sun.org.apache.exerces.internal.dom
org.apache.xerces.dom

The jar that contains the DocumentImpl of the NoClassDefFoundError is contained in the first jar. Please include this jar in the classpath before the second version of the jar.

Reference:
http://mail-archives.apache.org/mod_mbox/xerces-j-users/200407.mbox/%3C40F0D3AD.3050201@sun.com%3E

Mule Error: Application does not seem to be starting or is hanging

noreply@blogger.com (Jig) — Mon, 21 Apr 2008 16:40:00 +0000

Error:
Launching a JVM...
Error [125] in bind() call!
err:: Address already in use
Socket transport failed to init.
Transport dt_socket failed to initialize, rc = -1.
FATAL ERROR in native method: No transports initialized
JVM exited while loading the application.
------------------------------------------------------------------------
The JVM is being launched with a debugger enabled and could possibly be
suspended. To avoid unwanted shutdowns, timeouts will be disabled,
removing the ability to detect and restart frozen JVMs.
------------------------------------------------------------------------

The logs display the above error.

This indicates that the port for debugging is already in use, and not the actual mule application's port.

Change the debug port in the wrapper.conf.

wrapper.java.additional.5=-Xrunjdwp:transport=dt_socket,address=5295,server=y,suspend=y

CSS

noreply@blogger.com (Jig) — Wed, 09 Apr 2008 04:23:00 +0000

So, I'm creating a website and I'm noting some things down about CSS I'm learning from an actual site. Cool dudes.

CSS Styles

position: relative |

color: #ABC123
background-color: #ABC123
font:
font-size: XXXpx | XXX
width: XXXpx
margin: XXXpx
margin-bottom: XXXpx
margin-right:
padding:
text-align: center |
border: XXX

Lesson of the Day

noreply@blogger.com (Jig) — Mon, 31 Mar 2008 19:21:00 +0000

"We learn something new everyday!" As a tribute to this saying...

We have this large million of records table. An audit table exists to record every single update or deletion of a row in this table. We were thinking of creating an index on this audit table where no indexes existed before. However, every update/deletion would require an update of this new index, therefore, slowing the performance of write operations on this table.

Lesson of the Day: Indexes, although improves the performance of read operations, leads to more overheard if this table is often updated.

I know i'm dumb..

Flex Error: ReferenceError: Error #1065

noreply@blogger.com (Jig) — Sat, 29 Mar 2008 15:26:00 +0000

This error often refers to missing assets in the swf file that is expected to be there. For example, if you get the following error:

Variable ExampleView__embed_mxml__assets_png_example_picture_png_1012766830 is not defined.

It refers to a missing asset in an mxml file called ExampleView attempting to reference a png file as in the VBox below:

<mx:VBox backgroundImage="@Embed(source='/assets/png/example_picture.png')" width="100%"

In this instance, you must remember to include these assets into the compiled swf files.

Flash Global Security Settings: Windows vs. Macs

noreply@blogger.com (Jig) — Sat, 15 Mar 2008 05:42:00 +0000

There seems to be a slight difference between how global security settings are set on Windows and Macs browsers. To note, when you set the global security settings, they are set "globally" for the machine and not for the particular browser where the security setting was set.

On Macs, you can just specify the swf file in the global security settings. The swf file will load successfully and any external interface registered functions can be successfully called.

On Windows, however, specifying the swf file in the global security settings will allow the swf file to load correctly. But, this does not allow registered external interface functions to be called. It will cause the following js error:

Error calling method on NPObject! [plugin exception: Error in Actionscript. Use a try/catch block to find error.].

In order for external interface functions to be called, you must also specify the folder/file where the swf file is located.

CVS Commands

noreply@blogger.com (Jig) — Wed, 12 Mar 2008 15:26:00 +0000

Creating a New Tag from an Existing Tag
cvs -d :ext:{user}@{host}:/{cvs directory} -q rtag -r {existing tag} {new tag} {cvs directory}

java.lang.UnsatisfiedLinkError: create_stmt_c_copy

noreply@blogger.com (Jig) — Thu, 28 Feb 2008 19:04:00 +0000

Googling this, this is a result of old oracle jars. Update your oracle jars to the latest or the right version. This should fix this error.

Mule Error: ObjectNotFoundException Object " null" not found in container

noreply@blogger.com (Jig) — Thu, 28 Feb 2008 18:19:00 +0000

This error is not a very descriptive message. What is actually happening in the mule app is that the UMO is attempting to be created, however, it is throwing an error during its creation. The UMO is never then added to the container and therefore cannot be found in the container.

In the example that I encountered this error message, the creation of the com.bamnetworks.reporting.DataReporter fails to be created, because of a misconfiguration in the database and the reporting config.

SWFObject not working

noreply@blogger.com (Jig) — Mon, 11 Feb 2008 18:13:00 +0000

Please ensure that the div in which the flash embed object will be written to is defined before the inclusion of the external javascript file that defines the SWFObject

Otherwise, it will not be able to write to a div tag that does not yet exist.

Example:

...

<div id="flash_videoplayer"><strong>You need to upgrade your
Flash Player</strong> This is replaced by the Flash content. Place your alternate
content here and users without the Flash plugin or with Javascript
turned off will see this. Content here allows you to leave out <code>noscript</code>
tags. Include a link to <a href="swfobject.html?detectflash=false">bypass the detection</a> if you wish.</div>

...

<script type="text/javascript" src="js/flvplayer_2.js">

==========
The above flvplayer_2.js file contains the code below:

var swfObject = new SWFObject("FlvPlayer2.swf", "flvPlayer2", flv_width, flv_height, "9");
swfObject.addParam("allowScriptAccess", "always");
swfObject.addParam("allowFullScreen", "true");
swfObject.addParam("salign", "tl");
swfObject.addParam("menu", "false");
swfObject.addParam("wmode", "transparent");
swfObject.write("flash_videoplayer");

Removing a CVS tag

noreply@blogger.com (Jig) — Thu, 07 Feb 2008 17:39:00 +0000

The following commands will allow you to execute the cvs command without having to be in a cvs directory:

export CVS_RSH=ssh
cvs -d :ext:{user}@{host name or IP}:/source/cvs -q rtag -d {tag} {absolute location to module}

example:
cvs -d :ext:mtan@172.16.100.123:/source/cvs -q rtag -d MLB_
QA bamnet/tiers/web/axis2/modules/appaccount/auth-service

Axis2 Container Error: Processing Operations Modules ClassNotFoundException Error in loading message receiver

noreply@blogger.com (Jig) — Wed, 16 Jan 2008 17:29:00 +0000

Error:
org.apache.axis2.deployment.DeploymentException: ClassNotFoundException Error in l
oading message receiver tier.ws.migration.axis2.MLBUserWSInOutMessageReceiver; nested exception is:
java.lang.ClassNotFoundException: tier.ws.migration.axis2.MLBUserWSInOutMessageRec
eiver at org.apache.axis2.deployment.ServiceBuilder.populateService(ServiceBuilder.java:
329)

Cause:
You are attempting to use a service compiled in JDK 1.5 in a Axis2 container running under JDK 1.4.

Solution:
Compile the service using JDK 1.4

References:
http://www.mail-archive.com/axis-user@ws.apache.org/msg21397.html
http://issues.apache.org/jira/browse/AXIS2-1670

Decompressing a tgz file

noreply@blogger.com (Jig) — Mon, 14 Jan 2008 18:02:00 +0000

gzcat (file.tgz) | tar xvf -

or

tar -xzvf (file.tgz)