How to list multiple encrypted passwords in properties files

Jasypt is an extremely useful toolkit for encrypting and decrypting passwords. It provides simple instructions for those who want to use Spring and load properties files with encrypted passwords in them.

But, what if you need to provide a whole series of usernames and passwords. How would you accomplish this?
Jasypt's out-of-the-box implementations only read one encrypted value per key=ENC(value) pair in a property file.

Here's a solution:

1. Override the EncryptablePropertyPlaceholderConfigurer's convertPropertyValue() method. Then you can split a list like the following:
   

   listOfUsernamePasswords=LIST(username1,ENC(encryptedPassword1),username2,ENC(encryptedPassword2))

   into separate values and only send the encrypted values to the parent convertPropertyValue() implementation to get the decrypted values.
   
2. Sew the list back together as a string and return a value that now reads:
   

   username1,password1,username2,password2

3. You may be wondering as to who will do the work of breaking up these comma-separated values when they get to your spring bean? The answer is simple: Spring will! For ex: If you had configured you spring bean like so:
   

   <bean id="someBean" class="com.MyBean">
       <property name="multipleUsernamePasswords" value="${listOfUsernamePasswords}" />
   </bean>

   and the multipleUsernamePasswords property is of type String[] in MyBean class, then StringArrayPropertyEditor will be used implicitly, which will break it up into a string array auto-magically. If you are interested, you can read this blog about how various structures interpret property values for Spring.
   
   
4. Now its up to use that String[] to your advantage in your code.
   

Generating UML Diagramns with Maven

1. Install Graphviz. After installation confirm that it is part of your PATH.
2. Configure your maven pom files to make sure that you can get to the following repository: http://mirrors.ibiblio.org/pub/mirrors/maven2 because it has the second piece of the puzzle, the binaries for UMLGraph. You can see all the options for use in <additionalparam/> here.
   
3. To generate UML diagrams as part of the "mvn javadoc:javadoc" command, add the following (+/-) to your pom.xml file's <build/> section.
   
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-javadoc-plugin</artifactId>
           <configuration>
             <doclet>org.umlgraph.doclet.UmlGraphDoc</doclet>
             <docletArtifact>
               <groupId>org.umlgraph</groupId>
               <artifactId>doclet</artifactId>
               <version>5.1</version>
             </docletArtifact>
             <additionalparam>-views</additionalparam>
             <destDir>target/uml</destDir>
             <show>private</show>
           </configuration>
         </plugin>
4. To generate UML diagrams as part of the "mvn site" command, add the following (+/-) to your pom.xml file's <reporting/> section.
   
     <reporting>
       <plugins>
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-javadoc-plugin</artifactId>
           <reportSets>
             <reportSet>
               <id>uml</id>
               <configuration>
                 <doclet>org.umlgraph.doclet.UmlGraphDoc</doclet>
                 <docletArtifact>
                   <groupId>org.umlgraph</groupId>
                   <artifactId>doclet</artifactId>
                   <version>5.1</version>
                 </docletArtifact>
                 <additionalparam>-views</additionalparam>
                 <destDir>target/uml</destDir>
                 <show>private</show>
               </configuration>
               <reports>
                 <report>javadoc</report>
               </reports>
             </reportSet>
           </reportSets>
         </plugin>
       </plugins>
     </reporting>
5. That's it, you should now be reaping the benefits as your javadocs will have UML diagrams inside each class's landing page. I used the following post to put all this info together: http://wiki.wsmoak.net/cgi-bin/wiki.pl?UMLGraph

ResourceManager is only as good as the components you use it with

The flex framework provides many conveniences out-of-the-box, one of them being the ResourceManager. It works wells and until recently I thought one could do no wrong by it.

Yet, as I recently found out, even the most fool-proof components are only as good as the developer using them. Being someone who started working directly with Flex 4, I have had it way too easy. And sometimes I miss out on the bigger picture as I lack the fundamentals that someone who predates the flex 4 framework, would naturally have.

Recently I was faced with a surprising scenario where the ResourceManager had all the translations in various languages for a given key, yet it would always only load one set of translations. After loading the initial translation for a given language, it would simply refuse to update the label, even as I flipped through and tried to change the locales one by one.

The resources for the resource manager were being downloaded from the server side and loaded on the fly into the ResourceManager instance. Adobe has a very nice example of this on their live docs website. But the first translation for the first language to have appeared would stick around and not change!

Another colleague, who was not so naive as to simply take things at face value, pointed out to me that I was trying to use the ResourceManager too soon so perhaps the translation in my label was from a point in time when the rest of the translations had not made it over. But looking at IResourceManager we realized what a well-behaved component it is! As it makes an effort to fire-off change events in order to alert its users that perhaps now there are more exact/locale-specific translations for them to lookup. So what could possibly be wrong?

The AHA moment: my pre-flex-4 colleague noticed that the over-arching component containing the ResourceManager bindings was actually and since it did not implement, extend or mixin the event dispatcher functionality, it would NOT receive property change events! And as soon as I started using something like the problem disappeared.

It just goes to show you that frameworks cannot replace a competent and well-versed developer who excels in his/her area.