Methods and Apparatus for Dynamically Preloading Classes

A class preloading mechanism that dynamically preloads classes at runtime in a virtual machine (VM) environment. Data structures representing preloaded classes may be stored in a persistent module corresponding to a classloader. A persistent module can be directly mapped or copied into a memory region at runtime so that the classes may not have to be loaded from the class file container. The preloaded classes are not fully linked and resolved. When a classloader receives a class request, the classloader looks up the preloaded class in the memory region and completes linking and resolution of the class. Persistent modules may be pre-generated and, for example, installed with an application. Alternatively, a persistent module for a class file container may be generated at runtime by preloading classes from the class file container into a memory region and storing data structures representing the classes as a persistent module.