NetBeans 7.0 and 7.1 UML plugin

If you are using NetBeans 7.0 or 7.1, you probably can't find your UML plugin any more in the default repository.

From what I can read on the net, the team is working on the plugin rewriting it, and this will take a while.

Semi-broken solution

There is another way to install it, but beware, the plugin will be semi-broken, so jump down to another solution if you like to generate a pretty UML diagram from your code:

1. by the menu navigate to Tools -> Plugins;
2. select the "Settings" tab;
3. click the "Add" button;
4. as URL copy the following into the textbox:
   http://dlc.sun.com.edgesuite.net/netbeans/updates/6.9/uc/m1/dev/catalog.xml

Now on the tab "Available Plugins" there should be UML in category UML.

The problems are:

• "reverse engineering" command seem to work but you can't open the files;
• you can write a class diagram and work on it, but when you open your project next time you will unable to open the diagram again.

So all you can do is work on a temporary diagram, if you need only it.

Another solution

You can use yWorks UML Doclet community edition.
This solution will only let you generate a pretty UML diagram from your code.

1. Download the library from here;
2. right click on your java project in project explorer within NetBeans;
3. click on "Properties";
4. select  Build => Documenting;
5. on "Additional Javadoc Options" textbox paste the following (beware, I'm under windows):
   -docletpath "<yworks-uml-doclet-path>\lib\ydoc.jar" -resourcepath "<yworks-uml-doclet-path>\resources" -doclet ydoc.doclets.YStandard -umlautogen
   
   Where <yworks-uml-doclet-path> is the path of the yworks-uml-doclet folder.
   In my case <yid> is:
   E:\Users\retek\dev\lib\java\yworks-uml-doclet\yworks-uml-doclet-3.0_01-jdk1.5
6. click "OK";
7. right click on your java project in project explorer within NetBeans;
8. click Generate Javadoc;

Now, within your Javadoc you will have a very nice UML driagram for your classes.

Thanks to Matthew W. Johnson for this solution.

Javascript: variable_name is not defined

In Javascript, if your're are using a variable or a property and what you get is an error like "variable_name is not defined".
The message is pretty clear, but what is the best way to check and handle it?

There are some, but the best is:

   if (typeof my_variable === "undefined") {
      alert("my_variable is undefined");
   }

There are some others way, but they could have some problems, for example:

   if (my_variable === undefined) {
      alert("my_variable is undefined");
   }

This one doesn't work if in your scope is defined a variable called undefined.
This way also return true if my_variable is null.

Happy scripting =)