1. A system, comprising: at least one processor; and a memory storing program instructions executable by the at least one processor to implement a dynamic class reloading component configured to: determine that a previously loaded version of a class is not current with a class definition of the class in a class file; generate a new version of a body class for the class and a new version of a static body class for the class using bytecode from the class file, wherein the new versions of the body class and the static body class are given unique names; generate an instance of the new version of the static body class and set a static body class field of the class to refer to the instance of the new version of the static body class; for each existing instance of the class, generate an instance of the new version of the body class and set a body class field of the existing instance of the class to the corresponding instance of the new version of the body class; and load a new version of the class corresponding to the class definition of the class in the class file via a class loader for the class.