2,246 papers · page 80 of 113
We propose a heap compaction algorithm appropriate for modern computing environments. Our algorithm is targeted at SMP platforms. It demonstrates high scalability when running in parallel but is also extremely efficient when running single-threaded on a uniprocessor. Instead of u…
Programs that manipulate physical quantities typically represent these quantities as raw numbers corresponding to the quantities' measurements in particular units (e.g., a length represented as a number of meters). This approach eliminates the possibility of catching errors resul…
Tracing and reference counting are uniformly viewed as being fundamentally different approaches to garbage collection that possess very distinct performance properties. We have implemented high-performance collectors of both types, and in the process observed that the more we opt…
This paper describes a type system that is capable of expressing and enforcing immutability constraints. The specific constraint expressed is that the abstract state of the object to which an immutable reference refers cannot be modified using that reference. The abstract state i…
We identify three design principles for reflection and metaprogramming facilities in object oriented programming languages. Encapsulation: meta-level facilities must encapsulate their implementation. Stratification: meta-level facilities must be separated from base-level function…
Application programmer's interfaces give access to domain knowledge encapsulated in class libraries without providing the appropriate notation for expressing domain composition. Since object-oriented languages are designed for extensibility and reuse, the language constructs are …
Generics offer significant software engineering benefits since they provide code reuse without compromising type safety. Thus generics will be added to the Java language in the next release. While this extension to Java will help programmers when they are writing new code, it wil…
Java 1.5 will include a type system (called JSR-14) that supports parametric polymorphism, or generic classes. This will bring many benefits to Java programmers, not least because current Java practice makes heavy use of logically-generic classes, including container classes.
This paper proposes and implements a rigorous method for studying the dynamic behaviour of AspectJ programs. As part of this methodology several new metrics specific to AspectJ programs are proposed and tools for collecting the relevant metrics are presented. The major tools cons…
Code instrumentation is widely used for a range of purposes that include profiling, debugging, visualization, logging, and distributed computing. Due to their special status within the language infrastructure, the standard class libraries, also known as system classes provided by…
Through the design and implementation of a JVM that supports Pluggable Verification Modules (PVMs), the idea of an extensible protection mechanism is entertained. Link-time bytecode verification becomes a pluggable service that can be readily replaced, reconfigured and augmented.…
Java workloads are becoming more and more prominent on various computing devices. Understanding the behavior of a Java workload which includes the interaction between the application and the virtual machine (VM), is thus of primary importance during performance analysis and optim…
In an object-oriented language, a derived class may declare a method with the same signature as a method in the base class. The meaning of the re-declaration depends on the language. Most commonly, the new declaration overrides the base declaration, perhaps completely replacing i…
A discontinuity exists between object-oriented modeling and programming languages. This discontinuity arises from ambiguous concepts in modeling languages and a lack of corresponding concepts in programming languages. It is particularly acute for binary class relationships---asso…
This paper introduces dynamic object colocation, an optimization to reduce copying costs in generational and other incremental garbage collectors by allocating connected objects together in the same space. Previous work indicates that connected objects belong together because the…
Object-oriented programming languages provide a rich set of features that provide significant software engineering benefits. The increased productivity provided by these features comes at a justifiable cost in a more sophisticated runtime system whose responsibility is to impleme…
As improvements in processor speed continue to outpace improvements in cache and memory speed, poor locality increasingly degrades performance. Because copying garbage collectors move objects, they have an opportunity to improve locality. However, no static copying order is guara…
Predicate dispatch is an object-oriented (OO) language mechanism for determining the method implementation to be invoked upon a message send. With predicate dispatch, each method implementation includes a predicate guard specifying the conditions under which the method should be …
Distributed enterprise applications today are increasingly being built from services available over the web. A unit of functionality in this framework is a web service, a software application that exposes a set of "typed'' connections that can be accessed over the web using stand…
Inheritance is a useful mechanism for factoring and reusing code. However, it has limitations for building extensible systems. We describe nested inheritance, a mechanism that addresses some of the limitations of ordinary inheritance and other code reuse mechanisms. Using our exp…