Monday, February 15, 2016

Last Post

Hello every one, it's been a while since I started this blog. I enjoyed sharing my experience and knowledge during all these years, but its time to move on.

This is my last post in, from now on, I'm blogging in Spanish at: will stay online until October 2016, afterwards content will remain online but under another domain name (probably a blogger subdomain).

Best Regards,


Sunday, February 7, 2016

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see ya!

Friday, February 5, 2016

ADF Essentials 12.2.1 NoClassDefFoundError: org/antlr/runtime/RecognitionException

Hello all, just wanted to share the following regarding to ADF Essentials 12.2.1.

I configured Glassfish to support ADF applications and was able to deploy a demo application. However, when loading the just deployed application I got:

java.lang.NoClassDefFoundError: org/antlr/runtime/RecognitionException says that class is inside antlr-runtime*.jar So I searched inside Glassfish looking for that file but, of course, it wasn't there. Did a quick search in maven and downloaded the file to:


Restarted Glassfish and it's working now. However, why is this library not documented as needed in ADF Essentials documentation or Glassfish Configuration? I posted this question on oracle forums.

Hope it helps.

Tuesday, November 10, 2015

JavaOne and OOW 2015 Summary

Hello everyone! Finally I'm back after a great JavaOne and OOW 2015. In this post I'd like to share my experiences, some photos and a summary of the talks I attended.

Pre Conference
I flew to San Francisco on Saturday 24th 2015 via Copa Airlines CLO-PTY-SFO. Long trip from Colombia (about 8 hours).

I missed the Geek Bike Ride, a community event recommended to everyone who arrives to San Francisco on Friday (or before) since it starts at 8:30am on Saturday (I arrived at 15:00...). They crossed the Golden Gate Bridge to a little town called Sausalito, then they took a ferry back to San Francisco, really nice view.

At night, there was the Chinascaria, a Brazilian BBQ at Stephen Chin's house. Food was delicious and a great place for networking. A picture is worth a thousand words:

Day 1 (Sunday)
Sunday is the community day, so most of the talks are focused on User Groups. This day I attended the following talks: 
  • How to Run Your Own JUG's Java Conference [UGF11080]. It was a conference about how to run your own Java conference based on the experience of the Chicago Coder Conference creators. Lots of good advices for the conference we are planning to run next year at CLOJUG.
  • Improving Your Developer Career [UGF11081]. Two Brazilian Java Champions, Bruno Souza and Edson Yanaga shared some advices to improve your career, 9 simple tips you can follow in order to advance in your IT career. The message I liked the most was: "Take the control of your career, don't let others decide which way you should go".
  • Java Strategy Keynote. This is the day when the Strategy Keynote is delivered. This year the keynote lacked several features from the past: demos, news... The general feeling is that it wasn't a good keynote, but judge for yourself, watch the keynote on demand.
  • Coffee Potpourri: A Mixture of Everything Java [UGF11075]. This session was all about Q&A about everything in Java. A panel of JUG Leaders and Java Champions answered a set of about 30 questions. I answered a question regarding the use of the class Optional but I feel that I didn't explain well. What I meant was: Use the class Optional if you want to add meaning to your code, if you want your code to be more secure when someone else uses it. It's all about safe code.
  • JCP Meet the Executive Committee: Main Room [UGF11076]. In this session you get to know the JCP EC people and also you can get some beer! This is not a technical talk, but if your career is all about Java this session is a must.
At night, we were invited to the GlassFish, NetBeans, and OTN Party at the Thirsty Bear (a local brewer), where the JEspaƱol community shoot some videos with some of the Spanish speaking attendees.

Day 2 (Monday)
Officially this is the first day of the conference. Most of the talks I attended were Oracle ADF focused.
  • Component-Based Unit Testing of Oracle ADF Applications with Selenium [CON2866]. For those of you who develop ADF applications, you should know there is an open source project called ADF Selenium Tools which maps ADF components to page objects and thus provides convenient methods to interact with ADF applications. They showed a demo and it does work very well. Personally, I really liked this project because it eases the development of functional testing for ADF applications.
  • Oracle Alta UI Design: Implementing Oracle's Best Practices in Your Applications [CON8296]. ALTA UI a modern mobile and browser design system used by oracle in several products was discussed in this talk. The presenters shared tips about how to use the new design system in order to achieve really interactive an modern UI for your applications. Some of the tips are: 
    • Do not remove content in responsive design
    • Present an answer first, not a question
    • Make it easy to tap, touch, swipe
    • Many more...
  • Build Responsive Web Applications with Oracle ADF [HOL10380]. During this Hands-On-Lab we had the opportunity to experiment with the new features introduced in ADF 12.2.1 that let you create responsive UI in ADF Faces: the Masonry Layout, the af:matchMediaBehavior tag and the Responsive Template. With those three, responsive layouts can be achieve in ADF faces.
At night there was the JCP Party, best party during JavaOne. This one is organized by the JCP and is held at the Hilton. Great food, beverages and entertainment by The NullPointers band. Another space for networking.

Day 3 (Tuesday)
Second day of conferences:
  • Developing On-Device Mobile Apps with Oracle MAF[HOL10379]. The day started with a Hands-on-Lab where we had the opportunity to integrate Oracle MAF and Oracle MCS (Mobile Cloud Services). In order to do that we worked on Eclipse IDE since JDeveloper does not support Oracle MCS yet. Oracle MCS lets you integrate data from different backends, shape it and expose it as Restful services so your mobile apps can consume them.
  • Streams: The Real Powerhouse in Java 8 [CON8367]. Delivered by one of the best speakers I have ever seen: Venkat Subramaniam. This session was about Streams (and lambdas of course) in Java 8. Best practices and some advices, one of them: "Lambdas should not have side effects!"
  • Java Community Insider Secrets! [CON3891]. If you wanted to know about the Java Community, what it is, who can join, how to apply, etc. This session was for you! Great information, I wish I had attended a session like this one when I was starting in the Java community.
  • Ignite Session [IGN11289]. This is the first time I attend to the Ignite sessions. They are non-technical sessions delivered by recognized speakers like Arun Gupta, Venkat Subramaniam and others. Even 10 years old Andy Nilson (Kevin Nilson's son talked about mineraft). Presenters have 5 minutes to deliver their presentation. Slides move automatically after 5 seconds. It was fun!
  • Meet the Experts: Oracle’s Development Tools and Frameworks [MTE10022]. Explanatory session if you are into Oracle Tools development like Oracle ADF, MAF, etc. Specially to avoid the confusion with the new Oracle JET tool. When should I use what?

    In the afternoon we were interviewed at Nighthacking about JEspaƱol, the Spanish speaking community we are building:

    At night we attended a Jug leaders and Java Champions dinner at the Thirsty Bear. Lots of networking, we made contacts to bring Java Champions to Spanish Speaking countries next year (2016), Stay tuned!

    Day 4 (Wednesday)
    Attended just one session since I wanted to spend the day at the exhibition hall.
    • Oracle ADF and Oracle JDeveloper - What’s New and How to Use It [CON8333]. Session about the new features of ADF and JDeveloper 12.2.1. What I liked the most:
      • Support for Java SE 8 and Java EE 7
      • Expose AM as Rest Services (great for backend applications and code reuse)
      • New features for Responsive applications
      • Better Maven integration

    In the afternoon I was at Hackergarten contributing to the JSR 354: Money and Currency API examples. Feels good to contribute :)

    I also met Mohamed Taman, Java Champion from Egypt who was promoting his book about JavaFx

    At night, the Oracle Appreciation Event, at Treasure Island, Elton John and Beck were performing that night. Food, beverages, friends, networking... Not my kind of music though.

    Day 5 (Thursday)
    Last day of sessions, last day for networking, last day... you are really tired on Thursday and you jut want it to be over :)
    • Java Community Keynote [KEY8050]. Best Community Keynote ever!! watch it yourself on demand.

    In the afternoon I went to Duke's Cafe in order to have one last beer with some friends at JavaOne. See ya next year!

    Remember, conferences are all about networking, most presentations are available for download. Just visit the session catalog, filter according to your interests and download them for free!

    Saturday, July 25, 2015

    Packt Publishing Skill Up survey

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    see ya!

    Monday, May 18, 2015

    ADF BC i18n - Text Translation

    A common request on web applications is internationalization (i18n), specially the translation of text and data. In this post we are going to see how you can work with text translation within the ADF BC module of an ADF application and how to avoid common pitfalls.

    The samples showed in this post are based on the HR schema, specifically, on the Regions table.

    In order to provide text translation we first configure the ADF BC project Resource Bundle: Right click on project -> Project Properties

    From the above image:
    • Automatically Synchronize Bundle: Select to automatically create text resources in the resource bundle when editing UI components in the visual editor.
    • Warn About Hard-coded Translatable Strings: Select to display a message when a UI component being edited in the visual editor has an associated translatable string.
    • One Bundle Per Project or Per File: This configuration depends on your project. I like one bundle per project because most of my projects are developed in modules and every module is small, so one bundle is enough.
    • Resource Bundle Type: Properties Bundle is perhaps the most common type. List Resource Bundle may be difficult to edit and may cause problems when you have a lot of translatable text. Xliff is only important if you are using the same type in other Oracle applications.
    After you are done with the previous configuration, you can create your Entities, View Objects, Properties Sets... etc. And when you edit a translatable text, it will be added automatically to the resource bundle.

    Lets create an Entity based on the Regions table and add a new column called Description of type String:

    Lets modify the Control Hints of each attribute, specifically, lets change the Label Text property. Here we are using the Spanish translation for the name attribute of a region:

    After doing this for each attribute, we can inspect the entity's XML source code and notice the following:

    1. The attribute definition now has a Properties section where the key identifier for the attribute in the resource bundle is defined:

    2. Also, at the end of the XML file, the Entity's resource bundle definition is defined:

    If we open the above mentioned resource bundle file, we'll see something similar to this (we have added the Description_TXT key for later use):

    Now that we have a base resource bundle, lets create the English translation. Right click on the container package of our resource bundle and select New, in the popup under General, select File. Enter the same base name of our resource bundle and append an underscore and the code of the target language, in this case English is en. Copy the same keys but provide the text translated to English:

    Recommendation: If you are going to edit the resource bundle files, try to do it using JDeveloper option Edit Resource Bundles... under Application menu, since some characters are written to the file in UNICODE. For example, you can see that in Spanish accents and special characters are written in UNICODE.

    We can be more specific, for example, we can have a file for US English ( and a file for UK English ( but the general one works for now.

    Lets test what we have done so far. Create a default view object for the Regions entity and add it to an Application Module, then run the Application Module. Follow my previous post about the ADF BC Tester Locale Configuration if you want to be able to change the language from the ADF BC Tester application.

    You can notice that when we change the locale, the Label Text property of each attribute changes properly.

    Now lets try something more programmatic. Lets return the text for the Description attribute from our resource bundle. Open the Regions entity and under the Java section, click on the pencil icon and select the Generate Entity Object Class option and the Accessors option:

    This will create the RegionsImpl class where we can modify the text for the Description attribute. In the RegionsImpl class, modify the getDescription method to one of the following

    1. Use the oracle.jbo.common.StringManager to access to a hardcoded resource bundle:
    //In RegionsImpl
         * Gets the attribute value for Description, using the alias name Description.
         * @return the Description
        public String getDescription() {
            Locale locale = getDBTransaction().getSession().getLocale();
            return StringManager.getLocalizedString("com.javanme.model.res.ModelBundle",

    2. Use the oracle.jbo.common.StringManager class using the resource bundle definition of the Entity/ViewObject:
    //In RegionsImpl
         * Gets the attribute value for Description, using the alias name Description.
         * @return the Description
        public String getDescription() {
            Locale locale = getDBTransaction().getSession().getLocale();
            return StringManager.

    3. Use the java.util.ResourceBundle class to access to a hardcoded resource bundle:
    //In RegionsImpl
         * Gets the attribute value for Description, using the alias name Description.
         * @return the Description
        public String getDescription() {
            ResourceBundle res =
            return res.getString("Description_TXT");

    Using any of the above, we'll get the translated text for the Description attribute:

    Following are my notes about the above strategies:

    Strategy 1
    Uses the locale of the current DB Transaction. This is how you access the current locale in ADF BC without breaking the MVC architecture. Then uses the class oracle.jbo.common.StringManager, which is a singleton, in order to get a localized String from a Resource Bundle. Notice that this strategy uses a hardcoded resource bundle. I'd use this strategy if the Entity/ViewObject does not have defined a resource bundle in its XML file.
    You can learn more about the StringManager class in the API docs.

    Strategy 2
    Uses the locale of the current DB Transaction. This is how you access the current locale in ADF BC without breaking the MVC architecture. Then uses a class oracle.jbo.common.StringManager, which is a singleton, in order to get a localized String from the resource bundle defined in the XML file of the Entity/ViewObject. I'd use this strategy if the Entity/ViewObject does have defined a resource bundle in its XML file. This is my preferred strategy.
    You can learn more about the StringManager class in the API docs.

    Strategy 3
    Uses the locale of the current DB Transaction. This is how you access the current locale in ADF BC without breaking the MVC architecture. Then uses the class java.util.ResourceBundle in order to get a localized String. Notice that this strategy uses a hardcoded resource bundle. I would not use this strategy in ADF BC since it requires an extra configuration step which will be discussed in a moment.

    Strategies 1 and 2 are almost the same, the only difference is that one of them (2) uses the definition of the Entity's or ViewObject's resource bundle. 
    They both make use of the oracle.jbo.common.StringManager class, a singleton, for accessing localized Strings. Don't be afraid to use this class in your accessors methods, it won't create more than one instance and it will take care of the default locale of the JVM (this is really important! as we'll see next). Being part of the ADF framework, this is what the framework uses and recommends.

    Strategy 3 is a tricky one and it will look OK if we test it from the ADF BC Tester, but it may not work properly (I mean it won't localize our text properly) if, for example, we run an ADF Faces page that access our Regions Entity/ViewObject.
    If a resource bundle for the specified Locale does not exist, getBundle tries to find the closest match. In our example, if we are looking for the English translation ( and the default locale (Locale.getDefault()) is es_CO getBundle will look for the resources in the following order:
    • -> Because this is what we are looking for -> Found!!
    • -> Because this is Locale.getDefault()
    • -> Variant of Locale.getDefault()
    • -> When none of the above are found

    The above will work properly and the correct file will be read. Now let's try this: We need the Spanish translation ( in our example) and Locale.getDefault() returns en_US, getBundle will look for the resources in the following order:
    •  -> Because this is what we are looking for -> Not Found!
    • -> Because this is Locale.getDefault() -> Not Found!
    • -> Variant of Locale.getDefault() -> Found!!
    • -> When none of the above are found

    You can notice that the java.util.ResourceBundle class won't get my file but the file, because the latter is found first.

    This is why it is so tricky, if you don't have your resources named accordingly to their languages or if the JVM default locale (Locale.getDefault()) is different than your default language, it may not work properly. This is a common pitfall...

    So after all this, I hope you consider using the oracle.jbo.common.StringManager class over the java.util.ResourceBundle class when working with resource bundles in your ADF applications.

    see ya!


    About the ResourceBundle Class. Oracle [online].
    Available on Internet:
    [accessed on May 17 2015].

    Class StringManager. Oracle [online].
    Available on Internet:
    [accessed on May 16 2015].

    Binaries. Jobinesh's blog [online].
    Available on Internet:
    [accessed on May 14 2015].

    Wednesday, May 6, 2015

    International Day against DRM @PacktPub

    Just a quick post with a great offer from Packt Publishing:

    Today only! May 6th 2015, Packt Publishing is celebrating International Day against DRM and is offering all eBooks and Videos for $10

    More info:

    Go get yours!

    Thursday, April 30, 2015

    ADF BC Tester Locale Configuration

    Hi everyone. This is just a small post about how you can add more locales to the ADF BC tester in order to try your i18n at this layer. It's just about configuration (works on 11g and 12c), therefore, if you are interested in how to develop i18n for your ADF BC layer, you should wait for read my next post.

    ADF BC Tester is a great tool which allows us to test our ADF BC layer before we move to the ADF Faces layer, this is important since it will help us identify possible bugs in the right layer. By default the tester will launch in the locale defined for your application module:

    If you run the tester using the default configuration, you will end up with something like this:

    But if we want to try a different locale for your ADF BC layer, we need to change the application module locale configuration (shown above) before running the tester. However, this is not a good practice. The ADF BC Tester can be configured to show a menu with different locales to be used.
    In JDeveloper, go to Tools->Preferences->ADF Business Components->Tester:

    Add as many locales as you want and once you run your ADF BC Tester again, you will notice the new menu with the selected locales:

    see ya!

    Monday, April 13, 2015

    Java SE 7 End of Public Updates

    Oracle has announced the last public release of JDK 7 to be delivered on April 2015.

    This means that any security and bug fixes won't be available for public download but for Oracle customers only. You can, of course, download JDK 7 always, but the version you download after April 2015 won't have any new security or bug fixes.
    If you have applications developed with JDK 7 you can:
    1. Buy a commercial support of Java SE to become an Oracle customer.  You will keep getting updates of JDK 7 and several other benefits.
    2. Migrate to Java SE 8 and keep getting public updates of JDK 8 until 2017
    3. Do nothing... Your applications will continue to work as they do today (if run on JDK 7), but of course, there are security and performance risks.

    More info can be found in this link and on the following video:

    See ya!

    Friday, March 27, 2015

    Custom fonts in ADF 11g

    There are beautiful fonts you may want to use in your web applications. In this post I'm going to show you how you can use custom fonts such as Google Fonts in your ADF 11g Applications. For ADF 12c Applications, you can find more instructions here.

    What you need

    For JDeveloper 11gR1 you should download the ADF Skin Editor (download the latest release) since this version doesn't come with that tool integrated to the IDE. On the other hand, 11gR2 has the ADF Skin Editor tool integrated to JDeveloper.

    As a best practice you should create your own skin based on a skin provided by Oracle. That way, whenever you want to change the font of your entire application, there is only one place to make the change: the custom skin. This post is based on this best practice, so make sure you understand how to work with ADF skins.

    This is the font family we are going to use in this post. It's called Indie Flower

    Since ADF 11g skins make use of CSS2, the process of using custom fonts is not as easier as in 12c, but we have a workaround for that, just make sure you use a custom skin and a page template on your application.

    Custom fonts in ADF 11gR1 and 11gR2
    If you are using 11gR1, create the skin application using the skin editor. Steps are as follows (Remember, if you are using 11gR2 you can create the skin from within JDeveloper):
    Click on new application... Set the name and folder...
    Set the skin project name and the target application release that you want to skin:

    Then, create a new ADF Skin File (right click on project and select Create new ADF Skin File)

    Extend whichever Oracle skin you want, JDeveloper will suggest you one if you like. When the Skin Editor opens, go to Selectors and expand the Global Selector Aliases node and then Font, there you can see the class ADFDefaultFontFamily which is where we need to make the change in order to set the new font family for our entire ADF Application. Go to the Properties Inspector and make the change in the Font Family property:

    That's it, we have defined that all the components in an ADF application that uses this skin will use the custom font (except for those defined with a specific inlineStyle). However, if you notice we haven't told the skin file where the custom font is, that's because skins in 11g use CSS2 and so we can't define nor import the font in the skin file, if we do, it will get removed at runtime. The downside of this is that we can't use the skin editor to preview the font family change.

    If you are using ADF 11gR1, deploy the custom skin as an adfLib (right click on project -> deploy...) and import it into your ADF application.
    If you are using ADF 11gR2, this is not necessary since you can create the custom skin from within your project in JDeveloper.
    Anyway, remember to change the {WEB-INF}/trinidad-config.xml file to make use of your custom skin:


    The second part of the solution requires the use of Page templates, if you are not using page templates in your application, you will have to modify every single page where you want to use the custom font. The code you add to your page template or to your single page is the same:

    <af:resource type="css" source=""/>

    Here, we are adding a CSS resource where the custom font is defined. You may wonder where have the URL come from, well if you go to the Indie Flower font quick use, you will notice the URL is there.

    Wondering where to place the above code? If you are using page templates, place it right after the jsp:root tag, on the other hand, if you are using single pages, place it inside the document tag.

    Now, if you run an ADF application that makes use of your custom skin, all your components will be using the same font-family:

    Before using custom fonts

    After using custom fonts

    You should be aware that if you have components that set the font-family in the inlineStyle property or use any other custom class that overrides the font-family, then those components won't use the font-family defined in the skin.

    That's it, hopefully you now will be able to modernize your ADF 11g applications using new custom fonts.

    see ya!