I want to write an application in Java which is able to load JARs from a directory during runtime, add all classes inside to the classpath, load a spring context from the jar and instantiate the main class of it (it implements an Interface). If I add the JAR to the classpath before execution I am able to find the class which implements the interface and load it. I want to do this at runtime and call its functions using reflection (the list of methods will be listed by calling a function that is also noted in the interface). I think I need multiple class loaders and instantiate somehow. Does anyone know ho I can accomplish this?