Knuth Solved Puzzle

A pesar que yo no lo calcule ;P

Knuth habia puesto un puzzle en su segundo libro (mensaje encriptado con esquema RSA) de tal manera que fuese encontrado cuando ya no viviese (por lo caro del calculo), pero fue encontrado con metodos de


Por lo mismo un nuevo mensaje fue hecho:
http://www-cs-faculty.stanford.edu/~knuth/news12.html
Detalles del equipo NFS@Home project y Greg quienes encontraron el mensaje puede ser encontrado en:
http://escatter11.fullerton.edu/nfs/forum_thread.php?id=374
http://escatter11.fullerton.edu/nfs/forum_thread.php?id=373

The composite cofactor of the RSA public key factored into 91-digit and 97-digit prime numbers. With these factors, we are able to decrypt the RSA-encrypted literary quote. What quote did Donald Knuth hide so well?

91-digit prime factor:
4812118250596034474977589134243684231351843343856605196610181688401638676082217744120094291

97-digit prime factor:
1414213562373095048801688724209698078569671875376948073176679737990732478462107038850387534327641

With these and the previously known 25-digit prime factor, 1144729885849400174143427, we are able to decrypt the RSA-encrypted literary quote. The quote is the following:

His remarks (as reported) were as follows:--

"O Rowty-owty tiddly-owty
Tiddly-owty tiddly-owty
Highty-ighty tiddly-ighty
Tiddly-ighty ow."

--G. K. Chesterton (1905)

This is from The Tremendous Adventures of Major Brown, the first in the collection of short stories The Club of Queer Trades.

Todo un logro !!!!
Felicitaciones al equipo.

Fibonacci BigInteger

Leyendo los typos del Libro de Java Web Services: Up & Running primera edicion, usa de ejemplo a los números de Fibonacci:

"How many ways can this person traverse, say, a 100 meters? The answer is fib(100): 3,314,859,971." The 100th fibonacci number is 354224848179261915075. The is way over what a JAVA primary int can hold though. BigInteger can be used to calculate this bigger integer however.

Cual es muy usado en la enseñanza de programación de primeros cursos de universidad y también en series aritméticas.

El problema que el autor no calculo el crecimiento explosivo de tal serie y uso Integer de 32bit para el cálculo cometiendo un error en el numero de Fib(100).

Java Web Services: Up and Running by Scott Berkun; O'Reilly Media

Java Web Services: Up and Running by Scott Berkun; O'Reilly Media
http://shop.oreilly.com/product/0636920029571.do

2nd edition: RESTful context and more:
 
It has been recently released The second edition of Java Web Services: Up & Running, this means full new content (almost a trend in O'reilly Java titles), and not only an update of bugs and reader's comments.

This new edition focuses in the (not new, but fashion) RESTful services. Today, it is clear the current trend is to use less restrictive REST services and lightweight JSON. Keeping most chapters under this context, it get along with examples and info about WADL, Security JSON, etc.

Also, mentions different implementation Jersey, CXF, among others, so it reach a wider crowd for any doubts and details on these implementations. While in the client side has references to JAXB, Amazon, XStream, Axis.

SOAP Handler, using JAX-WS handlers, shows examples in how an incoming/outcoming SOAP message can be handled to implement business logic in the middle of the conversation; very useful for some security constraint inside of a typical workflow.

Last, but not Least, Security, another important tier on WS, it is covered with simple JAAS and SSL (or better said HTTPS), WS-Security.

Interesting is to mention several (perhaps most important) Java Application Servers, because most examples are using Tomcat, however take time and space to describe tips on
Source code, which is available to be downloaded from Git directly.

At the end, similar to the first edition, a not-so deep introduction the current de facto spec for webservices, giving a compass a quick answer about it.

Small and easy to read, not a cookbook, although several examples could be considered recipes.

WebLogic Server Default Encoding

A good question was asked at JavaRanch, regarding to parameter webapp.encoding.default

In the specification of JSP/Servelts set default to ISO-8859-1

There is a good summary in Japanese WebLogic Server documenttion, that for their context is a concurrent doubt.

http://otndnld.oracle.co.jp/document/products/wls/docs90/en/relnotes_ja.html#1110412

Component Name	Default Encoding
Servlet	ISO-8859-1
JSP	ISO-8859-1
XML format JSP Document	UTF-8
Tag File	ISO-8859-1
XML format Tag File	UTF-8

Since ISO-8859-1 encoding is extensively used as default encoding except for XML components, encoding setting is essential for the use of multibyte characters. The details of settings for each Web component are shown below. The meaning of each column in the table is as follows:

• Setting Location: Location where encoding is set.
• Effective Area: Area where the setting is effective.
• Setting Value: Character string used for setting.
• J2EE Compliant: YES for J2EE compliant, NO for WebLogic Server proprietary specification.
• Priority: The priority with which set value is used (the smaller the value, the higher priority). The lower priority will be overwritten by higher priority. In general, the one with smaller effective area will have higher priority, and vice versa.
• Setting Example: Examples of encoding setting.

Oracle WebLogic Server Schema home

A not very known, but useful page:

A list of WLS schemas, from 10.3.1 till 12.1.3 :

http://www.oracle.com/webfolder/technetwork/weblogic/index.html

http://xmlns.oracle.com/weblogic/weblogic-ejb-jar
http://xmlns.oracle.com/weblogic/weblogic-web-app

Among others...

Different info can be retrieved from these schema URLs, and check their version progression, i.e.:

weblogic-application.xml

List of schema versions for http://xmlns.oracle.com/weblogic/weblogic-application

1.0 : Released with WLS v10.3.1.0
1.1 : Released with WLS v10.3.3.0
1.2 : Released with WLS v10.3.4.0
1.3 : Released with WLS v10.3.6.0
1.4 : Released with WLS v12.1.1.0
1.5 : Released with WLS v12.1.2.0
1.6 : Released with WLS v12.1.3.0

Oracle WebLogic Server 12c Advanced Administration Cookbook

The last book of WLS 12.1.1, Packt brings us a 285 pages product, a comfortable size, not very big neither a flyer, so, easy to read and search as a reference, kind of cookbook with high availability and clustering point of view.

First pages are very detailed in how to install and run a vanilla WLS domain (including Node Manager, Machines, etc.). Including WLST and Admin Console. Some aesthetic tips, but not sure if this ha Administrator flavor.

Later comes deployments in different approaches (tools actually:) ). Next Chapter about High Availability and Clustering fine grained; address listen, Broadcasting, Unicast, Multicast, etc.

Then JDBC, again with HA/Clustering thru WLST/Admin Console... here it is more verbose about algorithms, Parameters of Data Sources, Gridlink, Multidatasource, a must for any Admin.

JMS, focused to HA again, using all typical resources of it: Bridges, Persistent Stores, etc.

A good, perhaps more useful , about monitoring, tips & tricks on this which is not very documented, and this time is very admin focused. Then recipes for WLS 12.1.1 troubleshooting for OutOfMemory (a very common scenario).

Finishing with security & SSL, concurrent questions and answer on this topic (X.509 certificates, keystore, etc.)

I can say that has some known areas, but improves in another that many times are left for the user, and it doesn't appear in the official documentation.  

http://www.packtpub.com/oracle-weblogic-server-12c-advanced-administration-cookbook/book

Eclipse Juno GUI (Theme)

1.
To change to older theme:

General --> Appearance --> Theme: Classic.

2.
Also, I found in this blog that it can be changed at lower level:


plugins\org.eclipse.platform_4.2.0.v201206081400\css

to something like,
plugins\org.eclipse.platform_4.2.0.v201206081400\css.old

Eclipse & Proxy Config

Necessary config when being behind a Firewall/Proxy:

use MANUAL Active-provider under General->Network Connections.

Clean the SOCKS option and only set HTTP & HTTPS with proxy values.

Probably related to bug: https://bugs.eclipse.org/bugs/show_bug.cgi?id=281472

Dudeney's Star Puzzle

Tomado textual de mathpuzzle.com Alex Ravsky encontro una solucion mejor para un puzzle de Dudeney.

Similar como el caso de Klondike de Sam Loyd en los 70s.


The task of the star puzzle, ((X36 = AM329) according to the list [Knu] by Donald E.
Knuth) published a century ago in The Strand Magazine [Dud2], is to construct a path,
consisting of 14 straight strokes, on the following field of stars from one light star to the
other such that all the stars lay on the path.

Paper original puede ser obtenido en http://arxiv.org/abs/1205.0747

Four on a Match

Kadon has many fun puzzles and some contests.

by solving one of them, I received Four on a Match two years ago:

I think it was good time to publish it :P