Crawljax can easily be extended through plugins. Any programmer with basic Java knowledge can write plugins using the documentation on this page.

When using maven, all Crawljax plugins should inherit from plugins parent pom.

The main interface is Plugin, which is extended by the different types of plugins. Each plugin type serves as an extension point that is called in a different phase of the Crawljax execution. To write a plugin you should implement one of the following plugin types.

Furthermore, if your plugin generates output in the form of files, it should implement the GenerateOutput inteface. This class gives you an easy way to get the absolute path the end-user would like to save any output files to.

Imagine we would like to log each dynamic DOM state as a static HTML page. We can easily add this functionality to Crawljax by creating a plugin that implements the OnNewStatePlugin interface. When a new state is visited the onNewState method is called with a session object as its parameter. This allows us to get the current DOM from the browser and log it to the console:

public class SamplePlugin implements OnNewStatePlugin {

    @Override
    public void onNewState(CrawlerContext context, StateVertex newState) {
        // This will print the DOM when a new state is detected. You should see it in your console.
        LOG.info("Found a new dom! Here it is:\n{}", context.getBrowser().getStrippedDom());
    }

    @Override
    public String toString() {
        return "Our example plugin";
    }
}

You can enable this plugin using the addPlugin method in the configuration builder.

• Example plugin
• Overview plugin