Java applications are composed of classes which are usually grouped and deployed using Java Archives. When an application is started, the hosting Java Virtual Machine (JVM) obtains the required classes one by one as they are needed from these archives. For this purpose, the JVM locates the related byte code by taking the names of the class and its package and evaluating the environment setting CLASSPATH. This works well as long as there is only one byte code matching the given class name, but it is not feasible when the byte code has to be selected among several classes with the same class name using properties such as version numbers or manufacturers. In this paper, we introduce so called Java Class Collections which enable the logical grouping of classes separately from their physical deployment within Java Archives and allow tagging them with supplementary properties used to select the right byte code. We illustrate the application of our approach for multi-application hosting and in remotely composable application systems.