extract class or jsp files from compiled package to send as patch for deployment

Question

I have java web application which is sent as ear for web-sphere deployment .

But in order to avoid downtime for minor patch fix we have to send the class file or jsp change at times

we use ant and jenkins to build , has someone used any script to extract such specific class file from compiled package to be packaged and sent in proper folder structure which can be used to just copy over the deployed environment?

We are on windows not on unix.

appreciate your response.

Answer 1

There are many ways to achieve this, here are some hints and information that might be useful for you to select the best way.

In general for production environments it is not recommended to replace single files as your packed application (ear) will not be synchronized with expanded one and changes might get lost on full resynchronization.

You can check the following page to get various options for partial updates - Updating enterprise application files:

• Full update - you replace whole application. To improve availability you could use:
  
  • Rollout update,
  • Procedure described here - Maintain continuous availability while updating WebSphere Application Server enterprise applications
  • Edition management feature from WebSphere 8.5.5
• Partial update - where you update single file, or set of files. Here are information how to prepare archive with files.
• Hot deployment - updating expanded application files

If you use Jenkins, you could create separate Job to gather updated files and prepare for example archive for partial update, rather than trying to extract files from package.