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

@Override
public void contextInitialized(ServletContextEvent sce) {

    ServletContext sc = sce.getServletContext();
    servletContext = sc;

    // Try and use one of the Servlet 3.0 methods that should be blocked
    try {
        sc.getEffectiveMajorVersion();
        log.append("FAIL-01");
    } catch (UnsupportedOperationException uoe) {
        log.append("PASS-01");
    } catch (Exception e) {
        log.append("FAIL-02");
    }
}
 

@Override
public void contextInitialized(ServletContextEvent sce) {

    ServletContext sc = sce.getServletContext();

    // Try and use one of the Servlet 3.0 methods that should be blocked
    try {
        servletContext = sce.getServletContext();
        sc.getEffectiveMajorVersion();
        log.append("FAIL-01");
    } catch (UnsupportedOperationException uoe) {
        log.append("PASS-01");
    } catch (Exception e) {
        log.append("FAIL-02");
    }
}
 

@Override
public void contextInitialized(ServletContextEvent sce) {

    ServletContext sc = sce.getServletContext();

    // Try and use one of the Servlet 3.0 methods that should be blocked
    try {
        servletContext = sce.getServletContext();
        sc.getEffectiveMajorVersion();
        log.append("FAIL-01");
    } catch (UnsupportedOperationException uoe) {
        log.append("PASS-01");
    } catch (Exception e) {
        log.append("FAIL-02");
    }
}
 

public static WebApiBinder newBinder(ApiBinder apiBinder) throws IOException {
    Environment environment = apiBinder.getEnvironment();
    Object context = environment.getContext();
    if (!(context instanceof ServletContext)) {
        return null;
    }
    ServletContext servletContext = (ServletContext) context;
    //
    // .MimeType
    MimeTypeSupplier mimeTypeContext = new MimeTypeSupplier(servletContext);
    mimeTypeContext.loadResource("/META-INF/mime.types.xml");
    mimeTypeContext.loadResource("mime.types.xml");
    apiBinder.bindType(MimeType.class, mimeTypeContext);
    //
    //.ServletVersion
    ServletVersion curVersion = ServletVersion.V2_3;
    try {
        environment.getClassLoader().loadClass("javax.servlet.ServletRequestListener");
        curVersion = ServletVersion.V2_4;
        servletContext.getContextPath();
        curVersion = ServletVersion.V2_5;
        servletContext.getEffectiveMajorVersion();
        curVersion = ServletVersion.V3_0;
        servletContext.getVirtualServerName();
        curVersion = ServletVersion.V3_1;
    } catch (Throwable e) { /* 忽略 */ }
    //
    // .Binder
    apiBinder.bindType(ServletContext.class).toInstance(servletContext);
    apiBinder.bindType(ServletVersion.class).toInstance(curVersion);
    //
    return new InvokerWebApiBinder(curVersion, mimeTypeContext, apiBinder);
}
 

@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, "/*");
    }
}