Patent · US Expired

Efficient computer based virtual machine object structure

US5920720A · kind A · utility

125Cited by
7References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 25, 1997
Grant dateJul 6, 1999
Priority date
Expiry dateFeb 25, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/449
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Method and apparatus for implementing a virtual machine interpreter such as an interpreter for interpreting Java compiled bytecodes. The Java language supports class structures and a hierarchy of such structures. As the Java software virtual machine loads the class file containing the Java bytecodes it allocates a first block, of memory based on the class definition for all dynamic methods implemented by a class hierarchy that includes a base class and any additional classes derived from the base class. The virtual machine instantiates instances of classes within a class hierarchy derived from the base class in other memory blocks by initializing a method table pointer at a base location in that other memory block for each such instance in the class hierarchy. The method table pointer is initialized to point to the first block of memory defining the dynamic methods for the class hierarchy. The interpreter also initializes other data unique to each instance at offsets relative to the method table pointer within the other memory block for said class instance. Practice of the invention enhances the speed with which the virtual machine accesses dynamic methods of objects within the cla…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.