version based jar file compilation

Hi,

I have a question related to version based compilation for jar files.

I have a jar file called jtools.jar for our application. I want to include all the versions of jtools.jar e.g. jtools_v_2_1.jar, jtools_v_2_2.jar, jtools_v_4_1.jar� into one single server. To make this possible, I need a class path that also includes the version number. For example, instead of having classes:

com.fisci.activity.adaptors.DoubleAdaptor.java

com.fisci.activity.adaptors.DateAdaptor.java

we want to have classes for version v_2_1:

com.fisci.v_2_1.activity.adaptors.DoubleAdaptor.java

com.fisci.v_2_1.activity.adaptors.DateAdaptor.java

and in a separate java structure for version v_2_2, we want to have classes:

com.fisci.v_2_2.activity.adaptors.DoubleAdaptor.java

com.fisci.v_2_2.activity.adaptors.DateAdaptor.java

and yet in another separate java structure for version v_4_1, we want to have classes:

com.fisci.v_4_1.activity.adaptors.DoubleAdaptor.java

com.fisci.v_4_1.activity.adaptors.DateAdaptor.java

The directory structure is simple:

com/fisci/v_2_1/adaptors/�

com/fisci/v_2_2/adaptors/�

com/fisci/v_4_1/adaptors/�

The question: is there a way in Java language that we can �version� the �import� statements? Example:

Instead of

import java.util.*;

import com.fisci.activity.adaptors.*;

we envision to have it in the form of:

import java.util.*;

import com.fisci.%version%.activity.adaptors.*;

Is there a �macro� in the form above (%version%) that we can it be replaced during compilation with let�s say v_2_2? (and compiler could take the �D symbolic definition what indicates version of interest is let�s say v_2_2)?

I will appreciate any suggestions...

Regards,
Vishal

Hi Vishal,

I would recommend the following...

Keep the package names as they are:

Use a directory structure like the following:

You might want to put the versions even higher up the directory tree.

When you are compiling or running a specific version just ensure that your classpath is pointing to the right files/directory.

I'm not aware of any way to do what you're asking and I don't believe that would be a wise choice in any case.

Jules

I concur with Julian. Making the version part of the package name is not a good idea. I create a jar for each version (for example: xyz-4.1.0.jar, xyz-4.1.1.jar and so on), and make sure that the approriate jar is in the classpath for whatever wants to use that version of the facility.