Wanted: Guice Injector Graphing
One of the nice new features of Guice 2.0 is the new introspection API. It's the equivalent ofjava.lang.reflect for Guice - it lets you inspect your application at runtime. Our goal is to make it easy to write rich tools for Guice. A natural use case is visualizing an application. The right graph can reveal the structure of your application. I've opened a feature request for this, Issue 213. I created a proof-of-concept to drum-up excitement for this idea.Example Graph: Application Code
class DeLorean {
@Inject TimeCircuits timeCircuits;
@Inject FluxCapacitor fluxCapacitor;
@Inject EnergySource energySource;
}
class FluxCapacitor {
@Inject TimeCircuits timeCircuits;
}
class TimeCircuits {
Date whereYouveBeen;
Date whereYouAre;
Date whereYourGoing;
}
interface EnergySource {
String generateOnePointTwentyOneGigawatts();
}
class Plutonium implements EnergySource {
public String generateOnePointTwentyOneGigawatts() {
return "newk-you-ler";
}
}Example Graph: Guice Configuration
Injector injector = Guice.createInjector(new AbstractModule() {
protected void configure() {
bind(EnergySource.class).to(Plutonium.class);
bind(FluxCapacitor.class);
bind(DeLorean.class);
}
});.dot File
My
Grapher code takes the above Injector and outputs a .dot file that describes a graph:digraph injector {
"FluxCapacitor" -> "FluxCapacitor.()" [arrowhead=onormal];
"FluxCapacitor" -> "TimeCircuits" [label=timeCircuits]
"DeLorean" -> "DeLorean.()" [arrowhead=onormal];
"DeLorean" -> "TimeCircuits" [label=timeCircuits]
"DeLorean" -> "FluxCapacitor" [label=fluxCapacitor]
"DeLorean" -> "EnergySource" [label=energySource]
"EnergySource" -> "Plutonium" [arrowhead=onormal];
} The Rendered Graph
Finally, Graphviz renders the
.dot file to a pretty picture:
This graph is a good start, but there's a long way to go. Unfortunately, I don't have the bandwidth to take this project to completion and am seeking a contributor. If you're interested, post a note on the issue. Coding is its own reward!
