Class JasperInitializer

java/org/apache/jasper/servlet/JasperInitializer.java:40–127

Initializer for the Jasper JSP Engine.

 * Initializer for the Jasper JSP Engine.
 */
public class JasperInitializer implements ServletContainerInitializer {

    /**
     * Constructs a new JasperInitializer.
     */
    public JasperInitializer() {
    }

    private static final String MSG = "org.apache.jasper.servlet.JasperInitializer";
    private final Log log = LogFactory.getLog(JasperInitializer.class); // must not be static

    /*
     * Preload classes required at runtime by a JSP servlet so that we don't get a defineClassInPackage security
     * exception.
     */
    static {
        JspFactoryImpl factory = new JspFactoryImpl();
        if (JspFactory.getDefaultFactory() == null) {
            JspFactory.setDefaultFactory(factory);
        }
    }

    @Override
    public void onStartup(Set<Class<?>> types, ServletContext context) throws ServletException {
        if (log.isDebugEnabled()) {
            log.debug(Localizer.getMessage(MSG + ".onStartup", context.getServletContextName()));
        }

        // Set up a simple default Instance Manager
        if (context.getAttribute(InstanceManager.class.getName()) == null) {
            context.setAttribute(InstanceManager.class.getName(), new SimpleInstanceManager());
        }

        boolean validate = Boolean.parseBoolean(context.getInitParameter(Constants.XML_VALIDATION_TLD_INIT_PARAM));
        String blockExternalString = context.getInitParameter(Constants.XML_BLOCK_EXTERNAL_INIT_PARAM);
        boolean blockExternal;
        if (blockExternalString == null) {
            blockExternal = true;
        } else {
            blockExternal = Boolean.parseBoolean(blockExternalString);
        }

        // scan the application for TLDs
        TldScanner scanner = newTldScanner(context, true, validate, blockExternal);
        try {
            scanner.scan();
        } catch (IOException | SAXException e) {
            throw new ServletException(e);
        }

        // add any listeners defined in TLDs
        for (String listener : scanner.getListeners()) {
            context.addListener(listener);
        }

        context.setAttribute(TldCache.SERVLET_CONTEXT_ATTRIBUTE_NAME,
                new TldCache(context, scanner.getUriTldResourcePathMap(), scanner.getTldResourcePathTaglibXmlMap()));