parser.java

业界著名的tomcat服务器的最新6.0的源代码。

            // There's a "<jsp:body" before the ETag

            // First, parse <jsp:attribute> elements:
            parseNamedAttributes(parent);

            result = true;
        }

        if (reader.matchesOptionalSpacesFollowedBy("<jsp:body")) {
            // ActionBody
            parseJspBody(parent, bodyType);
            reader.skipSpaces();
            if (!reader.matchesETag(tag)) {
                err.jspError(reader.mark(), "jsp.error.unterminated", "&lt;"
                        + tag);
            }

            result = true;
        } else if (result && !reader.matchesETag(tag)) {
            // If we have <jsp:attribute> but something other than
            // <jsp:body> or the end tag, translation error.
            err.jspError(reader.mark(), "jsp.error.jspbody.required", "&lt;"
                    + tag);
        }

        return result;
    }

    /*
     * Params ::= `>' S? ( ( `<jsp:body>' ( ( S? Param+ S? `</jsp:body>' ) |
     * <TRANSLATION_ERROR> ) ) | Param+ ) '</jsp:params>'
     */
    private void parseJspParams(Node parent) throws JasperException {
        Node jspParamsNode = new Node.ParamsAction(start, parent);
        parseOptionalBody(jspParamsNode, "jsp:params", JAVAX_BODY_CONTENT_PARAM);
    }

    /*
     * Fallback ::= '/>' | ( `>' S? `<jsp:body>' ( ( S? ( Char* - ( Char* `</jsp:body>' ) ) `</jsp:body>'
     * S? ) | <TRANSLATION_ERROR> ) `</jsp:fallback>' ) | ( '>' ( Char* - (
     * Char* '</jsp:fallback>' ) ) '</jsp:fallback>' )
     */
    private void parseFallBack(Node parent) throws JasperException {
        Node fallBackNode = new Node.FallBackAction(start, parent);
        parseOptionalBody(fallBackNode, "jsp:fallback",
                JAVAX_BODY_CONTENT_TEMPLATE_TEXT);
    }

    /*
     * For Plugin: StdActionContent ::= Attributes PluginBody
     * 
     * PluginBody ::= EmptyBody | ( '>' S? ( '<jsp:attribute' NamedAttributes )? '<jsp:body' (
     * JspBodyPluginTags | <TRANSLATION_ERROR> ) S? ETag ) | ( '>' S? PluginTags
     * ETag )
     * 
     * EmptyBody ::= '/>' | ( '>' ETag ) | ( '>' S? '<jsp:attribute'
     * NamedAttributes ETag )
     * 
     */
    private void parsePlugin(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node pluginNode = new Node.PlugIn(attrs, start, parent);

        parseOptionalBody(pluginNode, "jsp:plugin", JAVAX_BODY_CONTENT_PLUGIN);
    }

    /*
     * PluginTags ::= ( '<jsp:params' Params S? )? ( '<jsp:fallback' Fallback?
     * S? )?
     */
    private void parsePluginTags(Node parent) throws JasperException {
        reader.skipSpaces();

        if (reader.matches("<jsp:params")) {
            parseJspParams(parent);
            reader.skipSpaces();
        }

        if (reader.matches("<jsp:fallback")) {
            parseFallBack(parent);
            reader.skipSpaces();
        }
    }

    /*
     * StandardAction ::= 'include' StdActionContent | 'forward'
     * StdActionContent | 'invoke' StdActionContent | 'doBody' StdActionContent |
     * 'getProperty' StdActionContent | 'setProperty' StdActionContent |
     * 'useBean' StdActionContent | 'plugin' StdActionContent | 'element'
     * StdActionContent
     */
    private void parseStandardAction(Node parent) throws JasperException {
        Mark start = reader.mark();

        if (reader.matches(INCLUDE_ACTION)) {
            parseInclude(parent);
        } else if (reader.matches(FORWARD_ACTION)) {
            parseForward(parent);
        } else if (reader.matches(INVOKE_ACTION)) {
            if (!isTagFile) {
                err.jspError(reader.mark(), "jsp.error.action.isnottagfile",
                        "&lt;jsp:invoke");
            }
            parseInvoke(parent);
        } else if (reader.matches(DOBODY_ACTION)) {
            if (!isTagFile) {
                err.jspError(reader.mark(), "jsp.error.action.isnottagfile",
                        "&lt;jsp:doBody");
            }
            parseDoBody(parent);
        } else if (reader.matches(GET_PROPERTY_ACTION)) {
            parseGetProperty(parent);
        } else if (reader.matches(SET_PROPERTY_ACTION)) {
            parseSetProperty(parent);
        } else if (reader.matches(USE_BEAN_ACTION)) {
            parseUseBean(parent);
        } else if (reader.matches(PLUGIN_ACTION)) {
            parsePlugin(parent);
        } else if (reader.matches(ELEMENT_ACTION)) {
            parseElement(parent);
        } else if (reader.matches(ATTRIBUTE_ACTION)) {
            err.jspError(start, "jsp.error.namedAttribute.invalidUse");
        } else if (reader.matches(BODY_ACTION)) {
            err.jspError(start, "jsp.error.jspbody.invalidUse");
        } else if (reader.matches(FALLBACK_ACTION)) {
            err.jspError(start, "jsp.error.fallback.invalidUse");
        } else if (reader.matches(PARAMS_ACTION)) {
            err.jspError(start, "jsp.error.params.invalidUse");
        } else if (reader.matches(PARAM_ACTION)) {
            err.jspError(start, "jsp.error.param.invalidUse");
        } else if (reader.matches(OUTPUT_ACTION)) {
            err.jspError(start, "jsp.error.jspoutput.invalidUse");
        } else {
            err.jspError(start, "jsp.error.badStandardAction");
        }
    }

    /*
     * # '<' CustomAction CustomActionBody
     * 
     * CustomAction ::= TagPrefix ':' CustomActionName
     * 
     * TagPrefix ::= Name
     * 
     * CustomActionName ::= Name
     * 
     * CustomActionBody ::= ( Attributes CustomActionEnd ) | <TRANSLATION_ERROR>
     * 
     * Attributes ::= ( S Attribute )* S?
     * 
     * CustomActionEnd ::= CustomActionTagDependent | CustomActionJSPContent |
     * CustomActionScriptlessContent
     * 
     * CustomActionTagDependent ::= TagDependentOptionalBody
     * 
     * CustomActionJSPContent ::= OptionalBody
     * 
     * CustomActionScriptlessContent ::= ScriptlessOptionalBody
     */
    private boolean parseCustomTag(Node parent) throws JasperException {

        if (reader.peekChar() != '<') {
            return false;
        }

        // Parse 'CustomAction' production (tag prefix and custom action name)
        reader.nextChar(); // skip '<'
        String tagName = reader.parseToken(false);
        int i = tagName.indexOf(':');
        if (i == -1) {
            reader.reset(start);
            return false;
        }

        String prefix = tagName.substring(0, i);
        String shortTagName = tagName.substring(i + 1);

        // Check if this is a user-defined tag.
        String uri = pageInfo.getURI(prefix);
        if (uri == null) {
            reader.reset(start);
            // Remember the prefix for later error checking
            pageInfo.putNonCustomTagPrefix(prefix, reader.mark());
            return false;
        }

        TagLibraryInfo tagLibInfo = pageInfo.getTaglib(uri);
        TagInfo tagInfo = tagLibInfo.getTag(shortTagName);
        TagFileInfo tagFileInfo = tagLibInfo.getTagFile(shortTagName);
        if (tagInfo == null && tagFileInfo == null) {
            err.jspError(start, "jsp.error.bad_tag", shortTagName, prefix);
        }
        Class tagHandlerClass = null;
        if (tagInfo != null) {
            // Must be a classic tag, load it here.
            // tag files will be loaded later, in TagFileProcessor
            String handlerClassName = tagInfo.getTagClassName();
            try {
                tagHandlerClass = ctxt.getClassLoader().loadClass(
                        handlerClassName);
            } catch (Exception e) {
                err.jspError(start, "jsp.error.loadclass.taghandler",
                        handlerClassName, tagName);
            }
        }

        // Parse 'CustomActionBody' production:
        // At this point we are committed - if anything fails, we produce
        // a translation error.

        // Parse 'Attributes' production:
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        // Parse 'CustomActionEnd' production:
        if (reader.matches("/>")) {
            if (tagInfo != null) {
                new Node.CustomTag(tagName, prefix, shortTagName, uri, attrs,
                        start, parent, tagInfo, tagHandlerClass);
            } else {
                new Node.CustomTag(tagName, prefix, shortTagName, uri, attrs,
                        start, parent, tagFileInfo);
            }
            return true;
        }

        // Now we parse one of 'CustomActionTagDependent',
        // 'CustomActionJSPContent', or 'CustomActionScriptlessContent'.
        // depending on body-content in TLD.

        // Looking for a body, it still can be empty; but if there is a
        // a tag body, its syntax would be dependent on the type of
        // body content declared in the TLD.
        String bc;
        if (tagInfo != null) {
            bc = tagInfo.getBodyContent();
        } else {
            bc = tagFileInfo.getTagInfo().getBodyContent();
        }

        Node tagNode = null;
        if (tagInfo != null) {
            tagNode = new Node.CustomTag(tagName, prefix, shortTagName, uri,
                    attrs, start, parent, tagInfo, tagHandlerClass);
        } else {
            tagNode = new Node.CustomTag(tagName, prefix, shortTagName, uri,
                    attrs, start, parent, tagFileInfo);
        }

        parseOptionalBody(tagNode, tagName, bc);

        return true;
    }

    /*
     * Parse for a template text string until '<' or "${" or "#{" is encountered,
     * recognizing escape sequences "\%", "\$", and "\#".
     */
    private void parseTemplateText(Node parent) throws JasperException {

        if (!reader.hasMoreInput())
            return;

        CharArrayWriter ttext = new CharArrayWriter();
        // Output the first character
        int ch = reader.nextChar();
        if (ch == '\\') {
            reader.pushChar();
        } else {
            ttext.write(ch);
        }

        while (reader.hasMoreInput()) {
            ch = reader.nextChar();
            if (ch == '<') {
                reader.pushChar();
                break;
            } else if (ch == '$' || ch == '#') {
                if (!reader.hasMoreInput()) {
                    ttext.write(ch);
                    break;
                }
                if (reader.nextChar() == '{') {
                    reader.pushChar();
                    reader.pushChar();
                    break;
                }
                ttext.write(ch);
                reader.pushChar();
                continue;
            } else if (ch == '\\') {
                if (!reader.hasMoreInput()) {
                    ttext.write('\\');
                    break;
                }
                char next = (char) reader.peekChar();
                // Looking for \% or \$ or \#
                // TODO: only recognize \$ or \# if isELIgnored is false, but since
                // it can be set in a page directive, it cannot be determined
                // here. Argh! (which is the way it should be since we shouldn't
                // convolude multiple steps at once and create confusing parsers...)
                if (next == '%' || next == '$' || next == '#') {
                    ch = reader.nextChar();
                }
            }
            ttext.write(ch);
        }
        new Node.TemplateText(ttext.toString(), start, parent);
    }

    /*
     * XMLTemplateText ::= ( S? '/>' ) | ( S? '>' ( ( Char* - ( Char* ( '<' |
     * '${' ) ) ) ( '${' ELExpressionBody )? CDSect? )* ETag ) |
     * <TRANSLATION_ERROR>
     */
    private void parseXMLTemplateText(Node parent) throws JasperException {
        reader.skipSpaces();
        if (!reader.matches("/>")) {
            if (!reader.matches(">")) {
                err.jspError(start, "jsp.error.unterminated",
                        "&lt;jsp:text&gt;");
            }
            CharArrayWriter ttext = new CharArrayWriter();
            while (reader.hasMoreInput()) {
                int ch = reader.nextChar();
                if (ch == '<') {
                    // Check for <![CDATA[
                    if (!reader.matches("![CDATA[")) {
                        break;
                    }
                    start = reader.mark();
                    Mark stop = reader.skipUntil("]]>");
                    if (stop == null) {
                        err.jspError(start, "jsp.error.unterminated", "CDATA");
                    }
                    String text = reader.getText(start, stop);
                    ttext.write(text, 0, text.length());
                } else if (ch == '\\') {