How to get console output from Firebug HTML debugging in JavaFX Webview?

I'm using Firebug lite to debug the HTML elements in JavaFX webview. I'm using the below code.

engine.documentProperty().addListener(new ChangeListener<Document>() {
            @Override public void changed(ObservableValue<? extends Document> prop, Document oldDoc, Document newDoc) {
                enableFirebug(engine);
            }
        }); 
private static void enableFirebug(final WebEngine engine) {
        engine.executeScript("if (!document.getElementById('FirebugLite')){E = document['createElement' + 'NS'] && document.documentElement.namespaceURI;E = E ? document['createElement' + 'NS'](E, 'script') : document['createElement']('script');E['setAttribute']('id', 'FirebugLite');E['setAttribute']('src', 'https://getfirebug.com/' + 'firebug-lite.js' + '#startOpened');E['setAttribute']('FirebugLite', '4');(document['getElementsByTagName']('head')[0] || document['getElementsByTagName']('body')[0]).appendChild(E);E = new Image;E['setAttribute']('src', 'https://getfirebug.com/' + '#startOpened');}");

    }

I have a javascript which will print out the id's and name's of the elements onto firebug console, on every click on different HTML elements. I need to get this console output to my JavaFX application. Please help.

engine.getLoadWorker().stateProperty().addListener(new ChangeListener<State>() {
            @Override
            public void changed(ObservableValue<? extends State> observable,
                    State oldValue, State newValue) { 
                JSListener listener = new JSListener();

                JSObject jsobj = (JSObject) engine.executeScript("console.log = function(){"
                        + "var lastElement = null; "
                        + "document.addEventListener('click', function(e) {"
                        + "if (e.target != lastElement) {"
                        + "lastElement = e.target;"
                        + "java.log(lastElement.name);"
                        + "}}"
                        + ");"
                        +"}");                      
                jsobj.setMember("java", listener);  
            }
        });

Java Code :

public class JSListener { 

    public void log(String text) {
        System.out.println(text);
    } 
}

I'm using the below code to get the element ID. Please let me know where I'm going wrong!