Let's say you just thought of a cool new feature that you would like to
see added to Oracle JDeveloper. You could ask Oracle to
implement it, and if we
see enough demand for it, we might actually get it into the next
version. But if you are looking for a quicker turnaround time for this
feature, you might want to consider writing the extension on your own.
JDeveloper offers an extension SDK that you can use to add anything to
JDeveloper, from a new menu options, a new wizard or even a complete
new code editor.
But how do you go about doing this?
In this article we'll aim to cover the basic steps you might
want
to follow. We'll be using a sample extension project that adds a "go to
file" option to JDeveloper.
You can download the JDeveloper project for the extension from here.
Note: This article doesn't cover the JDeveloper extension sdk
architecture in deep details - the JDeveloper online help topic for the extension
SDK has more information about this.
Setting Up
When building extensions for JDeveloper you'll
probably want
to use
either the Java or J2EE edition of JDeveloper. You'll mostly be doing
straight Java coding and maybe a little Swing design. You'll also be
running JDeveloper in debug mode launching a complete JDeveloper to
test your extension. For these reasons, you'll want the lighter version
of
the tool to get better performance.
Once you have a JDeveloper installation set up, download the
extension SDK (ESDK) for JDeveloper. The
ESDK can be downloaded as an extension to JDeveloper through the
help->check for update menu.
The Extension SDK includes the jars you need in order to use the
extension API for JDeveloper, a new online help section about
building extensions, and a set of code samples.
After you download the ESDK it will offer to install the samples - go
ahead and install them - you'll get a workspace with projects
for
each extension sample.
If you actually want to see a specific extension in action you can
deploy it to the [jdev-root]\jdev\extensions directory and restart
JDeveloper.
Tip: To open the workspace in a later point of time use the
help->Open Extension Samples.
OK, we are done with the basic setup, next let's look at getting
started with coding and extension.
Developing an Extension
When you first start developing with a new technology, many of the
programs you build are created by coping
code from samples and then changing it to match your
needed functionality. This is probably the way to go with a JDeveloper
extension as well. The ESDK samples can provide you with your base code.
I would suggest that you first decide what type of UI your extension
needs. And then start by copying one of the ESDK samples. For example:
If you need to just add a menu option - copy FirstSample
If you need a dialog that will accept some input - copy
DialogBox
If you need a wizard that will accept input - copy
ClassGeneratorWizard
Tip: Several
of the extensions
developed by the community for JDeveloper are open-sourced,
this mean that you can look at their code as well to get some
programming tips.
In our project we want to let the user enter the name of the file in a
dialog and then navigate to that file and open it in
the editor. So we are going to use the DialogBox sample as the basis
for our extension. Here is the full code for our extension - let's look at the specific areas we changed.
Usually you'll start by modifying all the strings to match the text you want
for things like menu options etc. Then you'll get into modifying the actual extension code. For example adding a couple of additional items to your dialog layout. And of course you also want to hook-up your specific business logic to be executed when the extension is invoked.
In our sample we changed the name of the action in the following line
We then changed the dialog to show a drop down list - this section is
in the handleEvent method of our extension - this method is called when
the menu option is invoked.
In order to populate the list we needed to get a list of the files in
our project's directory and sub directories.
We wrote a specific method -populateFileListForProject - to achieve
this - and passed to it the base directory for our current active
project.
The only additional change we made to the ESDK code sample is to add a
keyboard accelerator by creating an accelerators.xml file and
registering it as part of the initialization method with the lines:
Now that you have a first cut of your code you'll want to test it -
right?
How do you test an extension to JDeveloper? Simply by
installing the extension and running JDeveloper.
In order for your extension to be installable you need to create an
extension.xml file in a META-INF directory.
You can just copy the text
for the file from one of the extension samples.
Then make sure to change the following:
id= should be the full path to your extension class
name and owner and description - any text that makes sense
addins should again have the full path to your extension class
<?xml
version="1.0" encoding="windows-1252" ?>
<extension xmlns="http://jcp.org/jsr/198/extension-manifest"
id="shay.org.ext.FileBrowser" version="1" esdk-version="1.0">
<name>Go To File</name>
<owner>Shay Shmeltzer</owner>
<dependencies>
<import>oracle.ide</import>
</dependencies>
<hooks>
<jdeveloper-hook
xmlns="http://xmlns.oracle.com/jdeveloper/1013/extension">
<addins>
<addin>shay.org.ext.FileBrowser</addin>
</addins>
</jdeveloper-hook>
<feature-hook>
<description>Adds a menu option that allows you to
quickly open any file
in your project's directory (ctrl alt -).</description>
<optional>true</optional>
</feature-hook>
</hooks>
</extension>
To learn more about the extension.xml file and the other
options you
can specify in the file check out the
[jdev-root]\jdev\doc\extension\ide-extension-packaging.html file in
your JDeveloper installation directory.
In order to deploy the extension, create a new JAR deployment
descriptor for your project - and specify that the JAR will get created
in the
[jdev-root]\jdev\extensions directory of your JDeveloper.
Also make sure that the JAR name will be your full class path in
addition to the version number you specified in the extensions.xml file.
Then just deploy the deployment profile to create the JAR.
Next we'll use a little trick that will let you run and debug
JDeveloper itself when your run your extension project.
Go into your project properties and edit your run/debug configuration
set the default run target to be the file
[jdev-root]\jdev\bin\jdev.conf. Now if you'll run your project a new
instance of JDeveloper will start and if you placed the JAR file in the
right location as described above your extension will be active.
If something is not working correctly then just set a breakpoint in
your extension code and instead of clicking the run button hit the
debug button to debug JDeveloper itself.
That's it - have fun fine-tuning your extension to work exactly as
expected.
Once you are done, it is time to distribute your extension.
Distributing Extensions
Starting with JDeveloper 10.1.3 extensions can be easily installed
through the help->check for update menu in JDeveloper.
In order for your extension to be installable in this way you'll need
to create a simple zip file that will contain your extension JAR as
well as a META-INF directory with a bundle.xml file.
Here is the content you need to put in your bundle.xml file.
<update-bundle version="1.0"
xmlns="http://xmlns.oracle.com/jdeveloper/updatebundle"
xmlns:u="http://xmlns.oracle.com/jdeveloper/update">
<!-- The id *MUST* match exactly the id in your
extension.xml. -->
<u:update id="shay.org.ext.FileBrowser">
<!-- The name of your extension
as you want it to appear under the check for update menu -->
<u:name>Go To
File</u:name>
<!-- The version *MUST* match
exactly the version in your extension.xml. -->
<u:version>1</u:version>
<u:author>Shay
Shmeltzer</u:author>
<u:author-url>http://blogs.oracle.com/shay/2007/07/10#a471</u:author-url>
<u:description>Adds a menu
option and keyboard short-cut (ctrl alt -) that
allows you to quickly navigate to and open any file in your
project's directory.</u:description>
</u:update>
</update-bundle>
Once you have the zip - you can test an installation by going through
the help->check for update and choosing to install from a local
file
- just point to the zip and you should be ok.
If you think other people might enjoy your extension you can host the
zip file somewhere on the Web, and let us know on the JDeveloper
discussion forum.
We'll then add your extension to the partners/open source update center
and people will be able to install your new extension directly from
inside JDeveloper with one click.
An even better idea would be to have your extension hosted as an open
source project (Google code, sourceforge etc) on one of the many open
source code hosting sites. This
way other people can help you enhance your extension and further
develop it.
Additional Information
To learn more about developing JDeveloper extensions visit the
following links:
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