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.KeyAdapter;
import java.awt.event.KeyEvent;
public aclass AComponent {
protected Component component;
private FrameKeyListener keyListener;
public final ComponentAccessor getComponent;
public final Event OnKeyTyped = new Event();
public AComponent(Component c) {
// init component
getComponent = new ComponentAccessor(c);
component = c;
// keyboard listener
keyListener = new FrameKeyListener();
component.addKeyListener(keyListener);
}
public static aclass ComponentAccessor returns Component {
private Component c;
public ComponentAccessor(Component c) {
this.c = c;
}
public static class Get {}
public react (Get g) {
return c;
}
}
private class FrameKeyListener extends KeyAdapter {
public void keyTyped(KeyEvent e) {
OnKeyTyped <-- new KeyboardEvent(e.getKeyChar());
}
}
}