JavaCloak: Reflecting on Java Typing for Class Reuse Using Proxies

Abstract

We discuss problems caused by the limitations of Java’s reflection mechanism in supporting the specialisation of run-time program behaviour in Java-Cloak. JavaCloak allows programmers to specialise the run-time behaviour of externally-developed code by using pre-generated source-level proxy objects. These proxy objects are of the same type as the original objects that they wrap. The runtime specialisation is achieved in two phases. Firstly, the programmer generates the proxies and tailors them to their local needs. The programmer then generates a JAR file of these proxy classes which is placed at the very start of the application's CLASSPATH variable. The virtual machine is thus diverted into loading the proxy classes instead of the original classes. At runtime the Java-Cloakrun time system accesses the wrapped classes and mediates object creation and method calls across the proxy/original boundary.