The JDevLibsForAnt extension provides a way to automatically maintain an Ant build file with information about a JDeveloper project.
Included are the source code, demo applications and an installable JDeveloper extension JDevLibsForAnt002-install.zip .

How to install the JDevLibsForAnt JDeveloper extension.

(update 07-2008 : recently Shay S. from Oracle has made the JDevLibsForAnt extension available in
the "Open Source and Partners Extensions" Update Center, which could be a more convenient way to install this.)

(1) Select "Help" > "Check for Updates..." in JDeveloper.
(2) On the "Check for Updates" wizard panel "Step 1 of 3: Source" select "Install From Local File" and click "Browse..."
(3) Select JDevLibsForAntApps\JDevLibsForAnt\JDevLibsForAnt\deploy\JDevLibsForAnt002-install.zip and click "Open".
(4) Click "Next" in the "Check for Updates" wizard.
(5) On the "Summary" panel, click "Finish".
(6) On the "Confirm Exit" dialog, answer "Do you want to restart now?" with "Yes".
(7) After JDeveloper has restarted, answer "Would you like to migrate from a previous version of JDeveloper?" with "No".

How to use the JDevLibsForAnt JDeveloper extension.

(1) Open the "Project Properties" dialog for a JDeveloper project where you want to enable the JDevLibsForAnt JDeveloper extension.
(2) Select the "JDevLibsForAnt" configuration panel.
(3) Enter an Ant build file name for "Output File Location", e.g. "build-libs.xml".
(4) (This step is no longer needed.)
(5) Click OK in the "Project Properties" dialog.
(6) Refresh the JDeveloper project and find the Ant build file "build-libs.xml" inside the "Resources" node.
(7) Find examples on how you could import and use such an Ant build file in Demo1Build\build.xml and Demo2Build\build.xml .

How to build the JDevLibsForAnt JDeveloper extension.

(1) Make sure you have installed the JDeveloper Extension SDK.
see http://www.oracle.com/technology/products/jdev/htdocs/partners/addins/index.html
(2) Open the JDevLibsForAntApps\JDevLibsForAnt\JDevLibsForAnt.jws application in JDeveloper.
(3) Select "Deploy to JAR file" in the JDevLibsForAnt-DP.deploy right-click menu.
(4) Run the "bundle-extension" Ant target in the build.xml Ant build file.

Read this before you run a jspx page in the demo applications:

Because it makes the example zip file significantly smaller, I removed the JSF JAR files.
It is easy to copy them back into the example from JDeveloper if you:
(1) configure your JDeveloper home in "build-setup.properties"
(2) run the "copy-jsf-jar-files" target in the "build-setup.xml" Ant buildfile

version history :
v0.02 : - using the JavaProject.getOutputDirectory() method suggested by Brian Duff in http://forums.oracle.com/forums/message.jspa?messageID=1851738#1851738
- refactored LibrariesProjectChangeListener, introducing JLFAProjectChangeListener, JLFAOptionsProjectChangeListener and OutputFileMerger
- added a context menu on project nodes to explicitly "merge", see JDevLibsForAntMenuHelper
v0.01 : initial version, also posted in forum thread "JDeveloper extension : JDevLibsForAnt", see http://forums.oracle.com/forums/thread.jspa?threadID=509945