Java, Classpath, Classloading => Multiple Versions of the same jar/project

Question

I know this may be a silly question for experienced coders. But I have a library (an http client) that some of the other frameworks/jars used in my project require. But all

Answer 1

You can use the URLClassLoader for require to load the classes from a diff-2 version of jars:

URLClassLoader loader1 = new URLClassLoader(new URL[] {new File("httpclient-v1.jar").toURL()}, Thread.currentThread().getContextClassLoader());
URLClassLoader loader2 = new URLClassLoader(new URL[] {new File("httpclient-v2.jar").toURL()}, Thread.currentThread().getContextClassLoader());

Class c1 = loader1.loadClass("com.abc.Hello");

Class c2 = loader2.loadClass("com.abc.Hello");

BaseInterface i1 = (BaseInterface) c1.newInstance();

BaseInterface i2 = (BaseInterface) c2.newInstance();