Kludge

Después de haber traducido un documento de Knuth, muchas palabras interesantes me llamaron la atención, entre otras fue kludge que significa una solución no inteligente a un problema en ingeniería, en este caso particular de computación.

UPDATE1 (2016.01.25): Que es diferente a la palabra que intenta crear (y popularizar) en honor a Turing:

"Nomenclaturing: Let's Ture to the Max!"

http://www-cs-faculty.stanford.edu/~uno/news12.html

Falsos Amigos Em Português

Después de estudiar Português por 1 año, pude hacer mi lista de vocabulario y donde me sorprendio varios aspectos de este idioma, entre otros la gran cantidad de amigos falsos que existen entre Castellano y Portugués:

Português	Castellano
acordar	despertar
acorde	despertar
apagar	apagar, borrar
apelido	sobrenombre
asa	ala de avion, pajaro
asas	alas
assim que	apenas (apenas pueda)
assiste	ver, ir
bater	pegar
batir	later
bilhete	billete, boleto, papeleta
biscoito	galleta
bistec	bife
bolo	queque
bolsa	cartera
borracho	goma (caucho)
cabo	cable
cachorro	perro
cafe de manha	desayuno
cafe passado	cafe de maquina
calça	pantalon
cartera	billetera (de hombre)
casaco	chaqueta mujer
cena	escena
costas	espalda
criado-mudo	velador
dados	datos
decorar	aprender de memoria, memorizar
descarga	tirar cadena
deslocada	dislocada, desplazado
despida	desnuda
dirigir	manejar, conducir
distinta	distinguida
encomendar	encargar
engano	equivocado
escritorio	oficina
feira	feria
feria	día de la semana, descanso
fraca	débil
irritada	enojada, molesta
latir	ladrar
mala	maleta
massa	pasta
mesmo	realmente
mesmo que	aunque
monte	montón
moral	moraleja
onda	ola
palavrão	garabato
pasta	paté
pasteis	empanada fritas
pegar	tomar
perdurar	colgar
pimenta	aji
pincel	isopo
presunto	jamón
pronto	listo, acabar
pulso	muñeca
que logo	de pronto
romancista	novelista
ruvia	pelirroja
seca	sequia, secado
segundo	según, segundo
senha	contraseña
serena	sirena
sino	campana
sobre tudo	casaca
sobremesa	postre
sobrenome	apellido
solo	suelo
tela	pantalla, televisor
termo	término
tirar	quitar, sacar
tomara que	ojala
tontura	mareo
traço	guión
traga	traiga
vaso	escusado, macetero
veia	vena

Sun Certified Enterprise Architect (SCEA)

Varias veces me han pregunto he insistido respecto la certificación Sun Certified Enterprise Architect (SCEA). La mayoria cree que se necesitan todos los certificados especificos de J2EE.

Como se ve en la figura (y pueden rectificar en la página), no tiene ningun requisito para poder tomarlo. Claro esta que no se recomienda ya que abarca todos los temas especializados.

Lo que si es diferente es que la forma de desarrollo del examen es diferente, cual consta de 3 partes: Examen, Proyecto, Ensayo. Mas parecido a una memoria de pre-grado.

Neo-vintage 2: Pagination in Struts... JSTL implementation

Many times I have needed to use an pagination for many data to be shown in my page, however there is no a good Tag implemented for Struts and not as JSF that has components for it..

There is a good encapsulation with the great library DisplayTag, but this one doesn't give too much freedom to create different things, thus this approach is more flexible.

Finally searching for the web I found a simple JSTL pagination, where you can give a collection of data and at level of presentation parse it and embedded with html and javascript we can get the final pagination that we wish.http://web.archive.org/web/20071213001753/http://www.ekcsoft.com/jstl/content/paginate/ (it is no longer alive).

It has a small bug when the collection is empty therefore the totalCount is zero.

It can be put inside Struts without problems, below can see code of it,:

<c:set var="totalCount" scope="session" value="${queryResults.rowCount}"/>
    <c:set var="perPage" scope="session" value="20"/>
    <c:set var="totalPages" scope="session" value="${totalCount/perPage}"/>
    <c:set var="pageIndex" scope="session" value="${param.start/perPage+1}"/>

   <c:if test="${!empty param.start && param.start >(perPage-1) && param.start !=0 }">
          <a href="?start=<c:out value="${param.start - perPage}"/>">Prev </a>
    </c:if>

   <c:forEach
        var="boundaryStart"
        varStatus="status"
        begin="0"
        end="${totalCount - 1}"
        step="${perPage}">
        <c:choose>
            <c:when test="${status.count>0 && status.count != pageIndex}">
                             <a href="?start=<c:out value='${boundaryStart}'/>">
                                <c:out value="${status.count}"/> |
                            </a>
            </c:when>
        <c:otherwise>
                <c:out value="${status.count}"/> |
        </c:otherwise>
        </c:choose>
    </c:forEach>

    <c:if test="${empty param.start || param.start<(totalCount-perPage)}">
          <a href="?start=<c:out value="${param.start + perPage}"/>">Next </a>
    </c:if>

Oracle JRockit: The Definitive Guide Review

Oracle JRockit: The Definitive Guide
Copyright © 2010 Packt Publishing

Just like the title establish, this is the definitive guide of JRockit, including the last features of version R28.

It starts with the canonical knowledge to work and understand the JVM, showing details from the most basic until the advanced topics. Describing how and why certain features were made, how it was improved and plus several Best Practices lists to take the best of the suite of tools bundle with JRockit.

The book is wisely divided in two parts, the first is about JVM and the second part is regarding to JRockit Mission Control. Which is a powerful set to dissect JRockit Beauvoir to find out memory leaks, performance, bottlenecks, etc.

It gives an extended explanation of the parameters to take better of this tools suite with a low overhead, many of the areas referred can't be found somewhere else in such deeply detail form.

Everything in only one compendium of information done by the same creators of JRockit.

 More information at:

• https://www.packtpub.com/oracle-jrockit-the-definitive-guide/book
• http://www.amazon.com/Oracle-JRockit-Definitive-Marcus-Hirt/dp/1847198066/ref=ntt_at_ep_dpt_1

Oracle JRockit: The Definitive Guide

This new book for JRockit will be release on June. It is written for specialist in the field.
https://www.packtpub.com/oracle-jrockit-the-definitive-guide/book

At first view it shows all the great enhancements has JRockit for tuning, analyzing, trouble-shooting, etc.

Martin Gardner QEPD

Lamentablemente Martin Gardner ha dejado de vivir, gran difundidor de las matemáticas recreativas.

A pesar de su avanzada edad todos seguiamos su legado que por muchos años nos inspiró en su mundo imaginario.

http://es.wikipedia.org/wiki/Martin_Gardner

WLS ListenAddress

When the WebLogic Server is set up to listen a specific port then it stops to listen even the loopback address (localhost/127.0.0.1), let's suppose you want to listen each local server where your application has been deployed.

And could appears many Exceptions related to, such as:

Failed to connect to t3://localhost:7003: Destination unreachable; nested exception is:

java.net.ConnectException: Connection refused; No available router to destination

java.net.ConnectException: t3://localhost:7003: Destination unreachable; nested exception is:

java.net.ConnectException: Connection refused; No available router to destination

at weblogic.rjvm.RJVMFinder.findOrCreate(RJVMFinder.java:203)

at weblogic.rjvm.ServerURL.findOrCreateRJVM(ServerURL.java:153)

at weblogic.jndi.WLInitialContextFactoryDelegate$1.run(WLInitialContextFactoryDelegate.java:344)

at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363)

at weblogic.security.service.SecurityManager.runAs(Unknown Source)

at weblogic.jndi.WLInitialContextFactoryDelegate.getInitialContext(WLInitialContextFactoryDelegate.java:339)

at weblogic.jndi.Environment.getContext(Environment.java:315)

at weblogic.jndi.Environment.getContext(Environment.java:285)

at weblogic.jndi.Environment.createInitialContext(Environment.java:208)

at weblogic.jndi.Environment.getInitialContext(Environment.java:192)

at weblogic.jndi.Environment.getInitialContext(Environment.java:170)

at weblogic.management.commandline.tools.AdminToolHelper.getMBeanHome(AdminToolHelper.java:590)

at weblogic.management.commandline.tools.ServerInfoCommandLineInvoker.doCommandline(ServerInfoCommandLineInvoker.java:924)

at weblogic.management.commandline.tools.ServerInfoCommandLineInvoker.(ServerInfoCommandLineInvoker.java:117)

at weblogic.management.commandline.AdminMain.main(AdminMain.java:132)

at weblogic.Admin.useAdminMain(Admin.java:43)

at weblogic.Admin.main(Admin.java:22)

Caused by: java.rmi.ConnectException: Destination unreachable; nested exception is:

java.net.ConnectException: Connection refused; No available router to destination

at weblogic.rjvm.ConnectionManager.bootstrap(ConnectionManager.java:464)

at weblogic.rjvm.ConnectionManager.bootstrap(ConnectionManager.java:315)

at weblogic.rjvm.RJVMManager.findOrCreateRemoteInternal(RJVMManager.java:251)

at weblogic.rjvm.RJVMManager.findOrCreate(RJVMManager.java:194)

at weblogic.rjvm.RJVMFinder.findOrCreateRemoteServer(RJVMFinder.java:225)

at weblogic.rjvm.RJVMFinder.findOrCreate(RJVMFinder.java:188)

... 16 more

The solution is to eliminate that configuration:

Through the GUI you can go to DOMAIN_NAME -> Environment -> Servers -> SERVER_NAME There you'll find a ``Listen Address'' input text. Leave it blank so WLS can listen to localhost otherwise only it will listen to the address entered.

In the config.xml you will see:

<server><name>AdminServer</name>
      <listen-port>7003</listen-port>
      <listen-address>www.devweb.cl</listen-address>
</server>

Restart the WLS and try out again, now it should be able to reach to localhost, doing a WLS Ping and deploying your application.

``If a server's listen address is undefined, clients can reach the server through an IP address of the computer that hosts the server, a DNS name that resolves to the host, or the localhost string. The localhost string can be used only for requests from clients that running on the same computer as the server.''

from: http://download.oracle.com/docs/cd/E12840_01/wls/docs103/ConsoleHelp/pagehelp/Corecoredomaindomainmonitorserverstitle.html#core.domain.domainmonitorservers.table.label.listenaddress

Simple WebLogic Ping

Many times someone wants to see if a WebLogic Server is up and running. This can be checked thru (even it has been deprecated still comes bundled in the last WLS 10.3.x ):

If you wish to use a more modern tool then use WLST, but then you should write more text for the same test.

java weblogic.Admin -url localhost:7001 -username weblogic -password  welcome1 -verbose PING 1 1024

---

Muchas veces se quiere ver si un WebLogic Server esta arriba y funcionando, esto se puede lograr con (a pesar que ha sido descontinuado aun viene dentro del WLS 10.3.x) :

java weblogic.Admin -url localhost:7001 -username weblogic -password  welcome1 -verbose PING 1 1024

Esta herramienta ya esta deprecada, pero aun sirve y es útil.

Si quieren usar una herramienta actual entonces pueden usar WLST, pero deben poner mas texto para poder hacer la misma prueba.

http://download.oracle.com/docs/cd/E11035_01/wls100/admin_ref/cli.html#wp1196567

Martin Gardner

After reaching Martin Gardner for a particular riddle, He wrote me telling me that he is not longer doing anything related to the subject and have donated all his library to Stanford University.

He always with a innovated progressive thinking...