Home
Up
(
Download )
Copyright Tristan Aubrey-Jones May 2008.
Abstract: A project investigating and developing an implicitly concurrent programming language, based on a metaphor taken from the physical world is reported. Uses a programming paradigm where programs consist of systems of autonomous agents, or active objects which communicate via message passing. A language enhancing Java with actors and linear types is presented. Example programs are written, compiled, and executed to evaluate the usefulness of the language. The language found to provide a familiar notation for implicit parallelism, and a compelling new model for concurrency, combining the performance of shared variables with the elegance of message passing.
Introductory Slides (PDF),
Report (PDF),
ActiveJava compiler prototype (ajavac),
ActiveJava runtime library (ajava_lang).
Examples:
calc - pocket calculator actor program
dining - dining philosophers actor program (never deadlocks)
sort - parallel quicksort implementation ("SortBenchmark" sorts 10,000 random integers using actors, java threads, and sequentially and compares)
To compile examples use:compile.bat ./calc compile.bat ./sort compile.bat ./diningTo run examples use:
run ./calc Main run ./dining Main run ./dining Main fast run ./sort Main run ./sort SortingBenchmark
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public aclass ADigitPad extends AContainer {
protected final GridLayout layout;
protected final ACharButton[] buttons;
public final Event OnClick = new Event();
public ADigitPad() {
// create panel
super(new JPanel());
layout = new GridLayout(4,3);
container.setLayout(layout);
buttons = new ACharButton[10];
createButtons(7); // 7,8,9,4,5,6,1,2,3,0
}
private void createButtons(int value) {
createButton(value);
if (value == 3) createButton(0);
else if (value % 3 == 0) createButtons(value-5);
else createButtons(value+1);
}
private void createButton(int value) {
buttons[value] = new ACharButton(Character.forDigit(value, 10));
buttons[value].OnClick <-- new Event.Subscribe(OnClick);
buttons[value].OnKeyTyped <-- new Event.Subscribe(OnKeyTyped);
this <-- new AddComponent(buttons[value]);
}
}