private void startSling()

in src/main/java/org/apache/sling/launchpad/webapp/SlingServlet.java [336:395]
52 lines of code
9 McCabe index (conditional complexity)

    private void startSling(URL launcherJar) {
        synchronized (this) {
            if (sling != null) {
                log("Apache Sling already started, nothing to do");
                return;
            } else if (startingSling != null) {
                log("Apache Sling being started by Thread " + startingSling);
                return;
            }

            startingSling = Thread.currentThread();
        }

        if (launcherJar != null) {
            try {
                log("Checking launcher JAR in " + slingHome);
                loader.installLauncherJar(launcherJar);
            } catch (IOException ioe) {
                startupFailure("Failed installing " + launcherJar, ioe);
                return;
            }
        } else {
            log("No Launcher JAR to install");
        }

        Object object = null;
        try {
            object = loader.loadLauncher(SharedConstants.DEFAULT_SLING_SERVLET);
        } catch (IllegalArgumentException iae) {
            startupFailure("Cannot load Launcher Servlet "
                + SharedConstants.DEFAULT_SLING_SERVLET, iae);
            return;
        }

        if (object instanceof Servlet) {
            Servlet sling = (Servlet) object;

            if (sling instanceof Launcher) {
                Launcher slingLauncher = (Launcher) sling;
                slingLauncher.setNotifiable(this);
                slingLauncher.setCommandLine(properties);
                slingLauncher.setSlingHome(slingHome);
            }

            try {
                log("Starting launcher ...");
                sling.init(getServletConfig());
                this.sling = sling;
                this.startFailureCounter = 0;
                log("Startup completed");
            } catch (ServletException se) {
                startupFailure(null, se);
            }
        }

        // reset the starting flag
        synchronized (this) {
            startingSling = null;
        }
    }