
One of the components of the GNU Compiler Collection (GCC) is GCJ, the
GNU Compiler for the Java programming language. GCJ is a compiler that can generate both native code and bytecode from Java source files. GCJ includes a runtime library (libgcj) that provides all runtime support, the core class libraries, a garbage collector, and a bytecode interpreter. Programs created by gcj can dynamically load and interpret class files or native shared libraries resulting in pure, or mixed native/interpreted apps.