pagecontextimpl.java

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            AccessController.doPrivileged(new PrivilegedAction(){
                public Object run(){
                    doSetAttribute(name, o, scope);
                    return null;
                }
            });
        } else {
            doSetAttribute(name, o, scope);
        }

    }

    private void doSetAttribute(String name, Object o, int scope ){
        if (o != null) {
            switch (scope) {
            case PAGE_SCOPE:
            attributes.put(name, o);
            break;

            case REQUEST_SCOPE:
            request.setAttribute(name, o);
            break;

            case SESSION_SCOPE:
            if (session == null) {
                throw new IllegalStateException(
                        Localizer.getMessage("jsp.error.page.noSession"));
            }
            session.setAttribute(name, o);
            break;

            case APPLICATION_SCOPE:
            context.setAttribute(name, o);
            break;

            default:
            throw new IllegalArgumentException("Invalid scope");
            }
        } else {
            removeAttribute(name, scope);
        }
    }

    public void removeAttribute(final String name, final int scope) {

        if (name == null) {
            throw new NullPointerException(
                    Localizer.getMessage("jsp.error.attribute.null_name"));
        }
        if (SecurityUtil.isPackageProtectionEnabled()){
            AccessController.doPrivileged(new PrivilegedAction(){
                public Object run(){
                    doRemoveAttribute(name, scope);
                    return null;
                }
            });
        } else {
            doRemoveAttribute(name, scope);
        }
    }

    private void doRemoveAttribute(String name, int scope){
        switch (scope) {
        case PAGE_SCOPE:
            attributes.remove(name);
            break;

        case REQUEST_SCOPE:
            request.removeAttribute(name);
            break;

        case SESSION_SCOPE:
            if (session == null) {
            throw new IllegalStateException(
                        Localizer.getMessage("jsp.error.page.noSession"));
            }
            session.removeAttribute(name);
            break;

        case APPLICATION_SCOPE:
            context.removeAttribute(name);
            break;

        default:
            throw new IllegalArgumentException("Invalid scope");
        }
    }

    public int getAttributesScope(final String name) {

        if (name == null) {
            throw new NullPointerException(
                    Localizer.getMessage("jsp.error.attribute.null_name"));
        }

        if (SecurityUtil.isPackageProtectionEnabled()){
            return ((Integer)AccessController.doPrivileged(new PrivilegedAction(){
                public Object run(){
                    return new Integer(doGetAttributeScope(name));
                }
            })).intValue();
        } else {
            return doGetAttributeScope(name);
        }
    }

    private int doGetAttributeScope(String name){
        if (attributes.get(name) != null)
            return PAGE_SCOPE;

        if (request.getAttribute(name) != null)
            return REQUEST_SCOPE;

        if (session != null) {
            if (session.getAttribute(name) != null)
                return SESSION_SCOPE;
        }

        if (context.getAttribute(name) != null)
            return APPLICATION_SCOPE;

        return 0;
    }

    public Object findAttribute(final String name) {
        if (SecurityUtil.isPackageProtectionEnabled()){
            return AccessController.doPrivileged(new PrivilegedAction(){
                public Object run(){
                    if (name == null) {
                        throw new NullPointerException(
                                Localizer.getMessage("jsp.error.attribute.null_name"));
                    }

                    return doFindAttribute(name);
                }
            });
        } else {
            if (name == null) {
                throw new NullPointerException(
                        Localizer.getMessage("jsp.error.attribute.null_name"));
            }

            return doFindAttribute(name);
        }
    }

    private Object doFindAttribute(String name){

        Object o = attributes.get(name);
        if (o != null)
            return o;

        o = request.getAttribute(name);
        if (o != null)
            return o;

        if (session != null) {
            o = session.getAttribute(name);
            if (o != null)
                return o;
        }

        return context.getAttribute(name);
    }


    public Enumeration getAttributeNamesInScope(final int scope) {
        if (SecurityUtil.isPackageProtectionEnabled()){
            return (Enumeration)
                    AccessController.doPrivileged(new PrivilegedAction(){
                public Object run(){
                    return doGetAttributeNamesInScope(scope);
                }
            });
        } else {
            return doGetAttributeNamesInScope(scope);
        }
    }

    private Enumeration doGetAttributeNamesInScope(int scope){
        switch (scope) {
        case PAGE_SCOPE:
            return attributes.keys();

        case REQUEST_SCOPE:
            return request.getAttributeNames();

        case SESSION_SCOPE:
            if (session == null) {
            throw new IllegalStateException(
                        Localizer.getMessage("jsp.error.page.noSession"));
            }
            return session.getAttributeNames();

        case APPLICATION_SCOPE:
            return context.getAttributeNames();

        default:
            throw new IllegalArgumentException("Invalid scope");
        }
    }

    public void removeAttribute(final String name) {

        if (name == null) {
            throw new NullPointerException(
                    Localizer.getMessage("jsp.error.attribute.null_name"));
        }

        if (SecurityUtil.isPackageProtectionEnabled()){
            AccessController.doPrivileged(new PrivilegedAction(){
                public Object run(){
                    doRemoveAttribute(name);
                    return null;
                }
            });
        } else {
            doRemoveAttribute(name);
        }
    }


    private void doRemoveAttribute(String name){
        try {
            removeAttribute(name, PAGE_SCOPE);
            removeAttribute(name, REQUEST_SCOPE);
            if( session != null ) {
                    removeAttribute(name, SESSION_SCOPE);
                }
                removeAttribute(name, APPLICATION_SCOPE);
            } catch (Exception ex) {
            // we remove as much as we can, and
            // simply ignore possible exceptions
        }
    }

    public JspWriter getOut() {
    return out;
    }

    public HttpSession getSession() { return session; }
    public Servlet getServlet() { return servlet; }
    public ServletConfig getServletConfig() { return config; }
    public ServletContext getServletContext() {
    return config.getServletContext();
    }
    public ServletRequest getRequest() { return request; }
    public ServletResponse getResponse() { return response; }


    /**
     * Returns the exception associated with this page
     * context, if any.
     * <p/>
     * Added wrapping for Throwables to avoid ClassCastException:
     * see Bugzilla 31171 for details.
     *
     * @return The Exception associated with this page context, if any.
     */
    public Exception getException() {
        Throwable t = JspRuntimeLibrary.getThrowable(request);

        // Only wrap if needed
        if((t != null) && (! (t instanceof Exception))) {
            t = new JspException(t);
        }

        return (Exception) t;
    }


    public Object getPage() { return servlet; }


    private final String getAbsolutePathRelativeToContext(String relativeUrlPath) {
        String path = relativeUrlPath;

        if (!path.startsWith("/")) {
        String uri = (String)
        request.getAttribute("javax.servlet.include.servlet_path");
        if (uri == null)
        uri = ((HttpServletRequest) request).getServletPath();
            String baseURI = uri.substring(0, uri.lastIndexOf('/'));
            path = baseURI+'/'+path;
        }

        return path;
    }

    public void include(String relativeUrlPath)
            throws ServletException, IOException {
        JspRuntimeLibrary.include(request, response, relativeUrlPath, out,
                  true);
    }

    public void include(final String relativeUrlPath, final boolean flush)
            throws ServletException, IOException {
        if (SecurityUtil.isPackageProtectionEnabled()){
            try{
                AccessController.doPrivileged(new PrivilegedExceptionAction(){
                    public Object run() throws Exception{
                        doInclude(relativeUrlPath, flush);
                        return null;
                    }
                });
            } catch (PrivilegedActionException e){
                Exception ex =  e.getException();
                if (ex instanceof IOException){
                    throw (IOException)ex;
                } else {
                    throw (ServletException)ex;
                }
            }
        } else {
            doInclude(relativeUrlPath, flush);