javax.servlet.ServletContext#getMajorVersion ( )源码实例Demo

@Advice.OnMethodEnter(suppress = Throwable.class)
@SuppressWarnings("Duplicates") // duplication is fine here as it allows to inline code
private static void onEnter(@Advice.Argument(0) @Nullable ServletConfig servletConfig) {
    if (alreadyLogged) {
        return;
    }
    alreadyLogged = true;

    int majorVersion = -1;
    int minorVersion = -1;
    String serverInfo = null;
    if (servletConfig != null) {
        ServletContext servletContext = servletConfig.getServletContext();
        if (null != servletContext) {
            majorVersion = servletContext.getMajorVersion();
            minorVersion = servletContext.getMinorVersion();
            serverInfo = servletContext.getServerInfo();
        }
    }

    logger.info("Servlet container info = {}", serverInfo);
    if (majorVersion < 3) {
        logger.warn("Unsupported servlet version detected: {}.{}, no Servlet transaction will be created", majorVersion, minorVersion);
    }
}
 

private void initializeContainer(final ServletContext context) {
	if(!initialized.compareAndSet(false, true)) {
		return;
	}
	final String serverInfo = context.getServerInfo();
	final int majorVersion = context.getMajorVersion();
	final int minorVersion = context.getMinorVersion();
	LOGGER.debug("Starting container {} {}.{}",serverInfo,majorVersion,minorVersion);
	Runtime.
		getRuntime().
			addShutdownHook(
				new Thread() {
					@Override
					public void run() {
						LOGGER.debug("Shutting down container {} {}.{}",serverInfo,majorVersion,minorVersion);
					}
				}
			);
}
 

@Advice.OnMethodEnter(suppress = Throwable.class)
@SuppressWarnings("Duplicates") // duplication is fine here as it allows to inline code
private static void onEnter(@Advice.This Servlet servlet) {
    if (alreadyLogged) {
        return;
    }
    alreadyLogged = true;

    ServletConfig servletConfig = servlet.getServletConfig();

    int majorVersion = -1;
    int minorVersion = -1;
    String serverInfo = null;
    if (servletConfig != null) {
        ServletContext servletContext = servletConfig.getServletContext();
        if (null != servletContext) {
            majorVersion = servletContext.getMajorVersion();
            minorVersion = servletContext.getMinorVersion();
            serverInfo = servletContext.getServerInfo();
        }
    }

    logger.info("Servlet container info = {}", serverInfo);
    if (majorVersion < 3) {
        logger.warn("Unsupported servlet version detected: {}.{}, no Servlet transaction will be created", majorVersion, minorVersion);
    }
}
 

@Override
public void contextInitialized(ServletContextEvent sce) {
    getLogger().debug("Executing contextInitialized");
    ServletContext servletContext = sce.getServletContext();
    if (servletContext.getMajorVersion() < 3) {
        return;
    }

    init(servletContext);
}
 

public static String getContextPath(ServletContext context) {
	// cette méthode retourne le contextPath de la webapp
	// en utilisant ServletContext.getContextPath si servlet api 2.5
	// ou en se débrouillant sinon
	// (on n'a pas encore pour l'instant de request pour appeler HttpServletRequest.getContextPath)
	if (context.getMajorVersion() == 2 && context.getMinorVersion() >= 5
			|| context.getMajorVersion() > 2) {
		// api servlet 2.5 (Java EE 5) minimum pour appeler ServletContext.getContextPath
		return context.getContextPath();
	}
	final URL webXmlUrl;
	try {
		webXmlUrl = context.getResource("/WEB-INF/web.xml");
	} catch (final MalformedURLException e) {
		throw new IllegalStateException(e);
	}
	String contextPath = webXmlUrl.toExternalForm();
	contextPath = contextPath.substring(0, contextPath.indexOf("/WEB-INF/web.xml"));
	final int indexOfWar = contextPath.indexOf(".war");
	if (indexOfWar > 0) {
		contextPath = contextPath.substring(0, indexOfWar);
	}
	// tomcat peut renvoyer une url commençant pas "jndi:/localhost"
	// (v5.5.28, webapp dans un répertoire)
	if (contextPath.startsWith("jndi:/localhost")) {
		contextPath = contextPath.substring("jndi:/localhost".length());
	}
	final int lastIndexOfSlash = contextPath.lastIndexOf('/');
	if (lastIndexOfSlash != -1) {
		contextPath = contextPath.substring(lastIndexOfSlash);
	}
	return contextPath;
}
 

/**
 * This method is adapted from ServerFactory.createInternalServlet.
 */
private void createInternalServlet(final ExtendedEnvironment env, final ServletContext context) {
    if (context.getMajorVersion() >= 3) {

        // Add the Task servlet
        final ServletRegistration.Dynamic taskServlet = context.addServlet("TaskServlet", new TaskServlet(env.getTasks()));
        taskServlet.setAsyncSupported(true);
        taskServlet.addMapping("/tasks/*");

        // Add the Admin servlet
        final ServletRegistration.Dynamic adminServlet = context.addServlet("AdminServlet", new AdminServlet());
        adminServlet.setAsyncSupported(true);
        adminServlet.addMapping("/admin/*");
    } else throw new IllegalStateException("The WizToWar adapter doesn't support servlet versions under 3");
}
 

@Override
public void onStartup(final Set<Class<?>> classes, final ServletContext servletContext) throws ServletException {
    if (servletContext.getMajorVersion() > 2 && servletContext.getEffectiveMajorVersion() > 2 &&
            !"true".equalsIgnoreCase(servletContext.getInitParameter(
                    Log4jWebSupport.IS_LOG4J_AUTO_INITIALIZATION_DISABLED
            ))) {
        final Logger LOGGER = StatusLogger.getLogger();

        LOGGER.debug("Log4jServletContainerInitializer starting up Log4j in Servlet 3.0+ environment.");

        final FilterRegistration.Dynamic filter =
                servletContext.addFilter("log4jServletFilter", Log4jServletFilter.class);
        if (filter == null) {
            LOGGER.warn("WARNING: In a Servlet 3.0+ application, you should not define a " +
                "log4jServletFilter in web.xml. Log4j 2 normally does this for you automatically. Log4j 2 " +
                "web auto-initialization has been canceled.");
            return;
        }

        final Log4jWebLifeCycle initializer = WebLoggerContextUtils.getWebLifeCycle(servletContext);
        initializer.start();
        initializer.setLoggerContext(); // the application is just now starting to start up

        servletContext.addListener(new Log4jServletContextListener());

        filter.setAsyncSupported(true); // supporting async when the user isn't using async has no downsides
        filter.addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), false, "/*");
    }
}
 

private boolean isJBossEap6(AsyncEvent event) {
    final ServletContext context = event.getSuppliedRequest().getServletContext();
    return context.getMajorVersion() == 3 && context.getMinorVersion() == 0 && System.getProperty("jboss.home.dir") != null;
}
 

public static boolean isGreaterThan(ServletContext context, int majorVersion, int minorVersion) {
    int contextMajorVersion = context.getMajorVersion();
    int contextMinorVersion = context.getMinorVersion();
    return (contextMajorVersion > majorVersion) || (contextMajorVersion == majorVersion && contextMinorVersion > minorVersion);
}
 

/**
 * Checks if is servlet spec 3 or higher.
 * 
 * @param context
 *            the context
 * @return true, if is servlet spec3 or higher
 */
public static boolean isServletSpec3OrHigher(ServletContext context) {
    if (context.getMajorVersion() >= 3) {
        return true;
    }
    return false;
}