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martes, 4 de julio de 2017

MySql tinyInt1isBit = false

Hoy una entrada rápida que puede salvar más de un problema una vez que tenemos nuestra base de datos ya definida o simplemente la hemos heredado de otra persona o proveedor.

Que ocurre si tenemos definido un campo en una tabla MySQL como tinyint, este es un campo que se usa para almacenar datos de 8bits es decir valores de 0 a 255.

Pero normalmente se utiliza para valor es boolean tipo true false. En mi caso hoy hemos tenido un problema porque tenemos una columna definida con este tipo de datos y en la tabla tenemos valores 0, 1, 2, etc.... El problema ha surgido porque el driver de mysql php ha traducido el valor correctamente pero el de java no lo ha hecho.

El driver de php traduce correctamente el valor 2, pero en Java nos devuelve el valor true. 

Curioseando por la web hemos visto que si en los parámetros de conexión de MySQL añadimos la siguiente cadena de conexión en la conexión java tinyInt1isBit=false el valor será interpretado correctamente como un 2.

Esto a más de uno le puede salvar de más de un problema.


miércoles, 18 de enero de 2017

Jboss datasources: how to set autocommit to false by default with example

Como cambiar el valor de autocommit  en los data sources de JBOSS  EAP 6.4 con ejemplo práctico:

In this post i´m going to resolve a problem with the jboss datasources, when you open a connection and get it throught a jboss datasource the autocommit mode is setted to true by default.

When you develop a new application where you can control all your code it is not a problem, but when you have  inherited code that you cant change it, for example in a migration from a weblogic to a jboss server it could be a real problem


In my case I had java code inherited from weblogic and in some place of the code i was suffering problems with the autocommit state of my jdbc connection. I could not do commit or rollback becasuse the autocommit was setted to true, and it throw the next exception

java.slq.SQLException: you cannot rollback with autocommit set!

This is because in weblogic 10.3 the jdbc connections have a extrange behavior because if you try to do a rollback with autocommit = true it has no effect butit doesn´t thow an exception. When you migrate this code to Jboss is a real problem that you have to handle.

In order to find a solution I have debugged the inherited code to looking for the classes that has been used to get the datasource connection. I found that the datasource class is WrapperDataSource 



In my case the solution was to create a Wrapper of the class WrapperDataSource in order to add the code to setAutoCommit(false) in the  getConnetion methods, in order to get the connection with autocommit setted to false by default, when the application instace a jdbc connection from Jboss server.


To do this we need to create a java project with the sources and the compiled classes of the this jar: ironjacamar-jdbc-1.0.31.Final-redhat-1.jar in order to modify and compile the WrapperDataSource class. This is the class that Jboss uses to create a new JDBC connection.

You can find this sources in the nex  link or in my github repository in the lib folder.

https://maven.repository.redhat.com/techpreview/all/org/jboss/ironjacamar/ironjacamar-jdbc/1.0.31.Final-redhat-1/

Also we need some jars in order to compile the WrapperDataSource class, the jars are those:

  • ironjacamar-core-api-1.0.31.Final-redhat-1.jar
  • ironjacamar-jdbc-1.0.31.Final-redhat-1.jar
  • jboss-connector-api_1.6_spec-1.0.1.Final-redhat-3.jar
  • jboss-logging-3.1.4.GA-redhat-2.jar
  • jboss-transaction-api_1.1_spec-1.0.1.Final-redhat-3.jar


All jars are in the Jbos EAP 6.4 distribution or in my github repository code too.

https://developers.redhat.com/products/eap/download/



Now in the java project with all the jars (added to the poject build path) and the source files we can make the modification that we need. We only need to create the package org.jboss.jca.adapters.jdbc and copy the class WrapperDataSource.java from the source files into it. If you need to modify more classes take it from the source code, copy in the project and modify it.



Next step is to look up the getConnection Methods and add the setAutocommit(false), after the connection creation,


Be carefull because in this version exists two getConnection methods and i have to modify both.

In next step you have to compile this class and mix with the original classes and create the new jar with my changes. In order to do this i have create an ant script (buidl.xml) into the ant folder which unzip the orginal, jar, compile the modified class and add to the new jar.

--

<?xml version="1.0"?>

<project name="WrapperDataSource" default="build" basedir=".">

 <property file="build.properties"/>
 
 
 <target name="clean" description="Deletes compiled and generated code">
         <delete dir="${build.dir}" />
 </target>
 
 <target name="build" depends="clean" description="build Wrapper">
  <mkdir dir="${build.dir}" />
  <unzip src="${build.dir}/../lib/ironjacamar-jdbc-1.0.31.Final-redhat-1.jar" dest="${build.dir}"/>
  <path id="lib.path.ref">
      <fileset dir="${lib.path.ref}" includes="*.jar"/>
  </path> 
  <javac srcdir="${source.dir}" destdir="${build.dir}" classpathref="lib.path.ref" target="1.6" 
 source="1.6" debug="true"/> <jar   destfile="${jar.dir}/${jar.name}"
         basedir="${build.dir}"         
  />
 </target></project>
--

To build the JAR with the new modified class, be sure to have Apache Ant installed, go to ant directory and execute the "ant" command.

The result shoud be:


The result is in the target/dist foder where you can find the new MyJbossWrapperDataSource.jar



Finally the last step consists in change the original ironjacamar-jdbc-1.0.31.Final-redhat-1.jar by the new MyJbossWrapperDataSource.jar modifiying the Jboss libray module.

To do this action you have to go to your JBOSS EAP6 installation and locate the next path:

[JBOSS_HOME]\modules\system\layers\base\org\jboss\ironjacamar\jdbcadapters\main\

Copy the new MyJbossWrapperDataSource.jar to this location



and modify the module.xml commenting the old jar file and adding the new MyJbossWrapperDataSource.jar

--
<module xmlns="urn:jboss:module:1.1" name="org.jboss.ironjacamar.jdbcadapters">
    <properties>
        <property name="jboss.api" value="private"/>
    </properties>

    <resources>
        <!--resource-root path="ironjacamar-jdbc-1.0.31.Final-redhat-1.jar"/>-->
        <resource-root path="MyJbossWrapperDataSource.jar"/>
        <!-- Insert resources here -->
    </resources>

    <dependencies>
        <module name="javax.api"/>
        <module name="javax.resource.api"/>
        <module name="javax.validation.api"/>
        <module name="org.hibernate.validator"/>
        <module name="org.jboss.as.naming"/>
        <module name="org.jboss.as.transactions"/>
        <module name="org.jboss.common-core"/>
        <module name="org.jboss.jboss-transaction-spi"/>
        <module name="org.jboss.ironjacamar.api"/>
        <module name="org.jboss.logging"/>
        <module name="org.jboss.threads"/>
        <module name="javax.xml.stream.api"/>
    </dependencies>
</module>

--

You can download my eclipse project from github in the next link, if you want to get the code with this change appied, or make more changes in your jboss datasource.

https://github.com/antuansoft/MyJbossWrapperDataSource

Happy Wrapping!!!


martes, 27 de diciembre de 2016

Weblogic 10.3.6: local queue creation

Weblogic 10.3.6: Creación de colas locales


Sometimes in weblogic server is needed to create some local queues in order to process different types of messages.

This is the steps needed to create a very basic queue in weblogic.

The main objetive is to create one queue in weblogic.

1 - JMS Server creation: 

This is a basic container for de the queues.

  • Go to services -_> Messaging-->Jms Servers
  • Press New and create a new JMS Server: It is the container for queues.
  • Name the new JMS, por example: MyJmsServer and press next.

  • Finally select the server where you want to deploy your Jms Server



  • The final result is that you have created a new JmsServer associated to your Server.




2 - JMS Module creation: 

This step is to create a JMS module where you can assign resources and configure your queues. This module is similar to a J2EE module where configure your jndi resources.


  • Go to JMS Modules and create a new module, for example CSBModule, this is a module related to my CSMB project.

  • Name the module.

  • Asign to a server.
  • The final result is a JMS module asociated to the Server.



3 - Subdeployment creation: 

A subdeployment is a mechanism by which JMS module resources (such as queues, topics, and connection factories) are grouped and targeted to a server resource (such as JMS servers, server instances, or cluster).

Is a place where all the queues and resources which we are going to create will be placed, we are going to asociate to the JMS Server created in step 1.


  • Go to the new JmsModule creante and go to subdeployments tab and create new one


  • Name the subdeployment, for example AdminServerJMS


  • Associate it to the JMS Server create in step 1.

  • The result is a subdeployment associated to the JMS Server and through this server to the admin server.




4 - Conection Factory creation: 

In order to create a queue, the first step is to create a connection factory and after that the queue and asociate it to this factory.

A connection factory is a resource that enables JMS clients to create connections to JMS destinations.

  • Go to JMSModules --> CSMBModule and press new 

  • Create the connection factory 

  • Name it  (CFCSMB) and give a jndi name (jms/CFCSMB)

  • Asociate to the server.

  • The final result is a connection factory like that:


5 - Queue creation: 

Now we are ready to create the queue

  • Go to JMSModules --> CSMBModule and press new 
  • Create the new queue

  • Name it (CSMB_BT_IN) and give a jndi name (jms/CSMB_BT_IN)

  • Associate it to the sub-deployment and target to the JMS Server.

  • The final result is like that


This are all the steps needed to create a Queue in weblogic 10.3.6 associated to a JNDI-NAME.




jueves, 15 de diciembre de 2016

Weblogic Jboss Migration issue 1: javax.naming.NameNotFoundException: env/jmx/runtime



Migración Weblogic - Jboss problema 1: obtener el Servidor MBeans


I my new job, we have to migrate original web applications deployed in a Weblogic 10.6.3 Application Server to Jboss EAP6 (Jboss AS7).

This post is about the first problem that i have found. The problem is how to instantate the MBeanServer object that containts all my beans.


The slice of code that instantate a the MBeanServer in weblogic is like that:

//Weblogic way
InitialContext ctx = new InitialContext();
this.mbs = ((MBeanServer)ctx.lookup("java:comp/env/jmx/runtime"));

If you deploy this code in a JBoss, the common error that appears in log is the next one:
javax.naming.NameNotFoundException: env/jmx/runtime

The way to solve this issue is change the context lookup for a FactoryManager 
to get the right MBeanServer.

//JBoss way
import java.lang.management.ManagementFactory;
//another code
//another code
//.....
this.mbs=ManagementFactory.getPlatformMBeanServer();

The good news is that this way works both in Jboss and Weblogic.


viernes, 4 de noviembre de 2016

VirtualBox Centos 6 problems installing VboxGuetsAditions

Today I have installed a Centos 6 in my VirtualBox machine and i tried to create a shared folder to interchange file between de host and guest machine.







I have tried to add the GuetsAditions "inserting" the CD and installing



When i tried to install the software executing the autorun.sh




I recived in the same window the next error:

Look at /var/log/vboxadd-install.log to find out what went wrong

When I opened the file the error is the next one:

Makefile:181: *** Error: unable to find the sources of your current Linux kernel. Specify KERN_DIR= and run Make again. Stop


The problem is that you not have installed all the linux headers properly in your machine.

I recommend two steps:

1 - yum update 

In order to update all your virual machine specially if have been recently installed.

2 - yum install kernel-devel 

This package provides kernel headers and makefiles sufficient to build modules against the kernel package.

Restart your Centos virtual machine and try to execute again the autorun.sh

Evething works!!!





viernes, 24 de julio de 2015

X11 connection rejected because of wrong authentication

Esta vez me está tocando trabajar con sistemas un poco antiguos, aquí estamos utilizando un aplicación que WEB que está compilada con JDK1.5, y realizada con Spring y iBatis.

El servidor de aplicaciones es un JBOSS (jboss-4.2.3.GA) donde se carga el war de la aplicación, todo el frontal está hecho con jsf y richfaces. La aplicación está corriendo sobre Linux.¡

El problema que me ha pasado es que una vez delplegada la aplicación en el servidor JBOSS, todo ha ido perfectamente pero al poner en el navegador la URL de acceso a la aplicación esta no cargaba porque de repente el proceso java asociado al servidor de aplicaciones desaparecía.

El proceso de repente no estaba en el listado de procesos activos, y he intentado arreglarlo en principio comprobado que la memoria del proceso no era excesiva, y después ampliándola pero el proceso seguía igual.

Revisando los LOGS la única traza visible era:


18:51:15,521 INFO  [STDOUT] 16/07/2015 18:51:15 DEBUG (es.mi.sd.xxxxx.aspect.ServiceLoggerAspect)  - <<<<<<<<<<<<<<<<<
X11 connection rejected because of wrong authentication.

X connection to localhost:11.0 broken (explicit kill or server shutdown).


La manera de solucionarlo ha sido poner esta línea en los parámetros de arranque de JBOSS,

-Djava.awt.headless=true

Nuestro arranque ha quedado así:

JAVA_OPTS="-Xms512m -Xmx512m -XX:MaxPermSize=1024m -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000 -Djava.awt.headless=true"


Ahora el procedimiento sigue vivo y no muere al cargar la primera página de la aplicación.

Referencias:

- Referencia 1

lunes, 9 de febrero de 2015

WSO2: add log4j traces for your service

When you are using WSO2 application server to create your web services, you may want to log debug traces in your web services, but by default the log4j WSO2 configuration doesn't show this kind of debug traces.

In order to show this debug messages you only need to consider your webservice implementation package and add it to log4j WSO2 configuration.

Imagine that your application or webservice package is com.antuansoft.myapp you have to add this lines:

#MY APP DEBUG TRACES:
log4j.logger.com.antuansoft.myapp=DEBUG


at the end of the log4j.properties file that is situated in the next path:

[WSO2-Intallation-path]/repository/conf/log4j.properties