parser.java

业界著名的tomcat服务器的最新6.0的源代码。

                    if (!reader.hasMoreInput()) {
                        ttext.write('\\');
                        break;
                    }
                    ch = reader.nextChar();
                    if (ch != '$' && ch != '#') {
                        ttext.write('\\');
                    }
                    ttext.write(ch);
                } else if (ch == '$' || ch == '#') {
                    if (!reader.hasMoreInput()) {
                        ttext.write(ch);
                        break;
                    }
                    if (reader.nextChar() != '{') {
                        ttext.write(ch);
                        reader.pushChar();
                        continue;
                    }
                    // Create a template text node
                    new Node.TemplateText(ttext.toString(), start, parent);

                    // Mark and parse the EL expression and create its node:
                    start = reader.mark();
                    parseELExpression(parent, (char) ch);

                    start = reader.mark();
                    ttext = new CharArrayWriter();
                } else {
                    ttext.write(ch);
                }
            }

            new Node.TemplateText(ttext.toString(), start, parent);

            if (!reader.hasMoreInput()) {
                err.jspError(start, "jsp.error.unterminated",
                        "<jsp:text>");
            } else if (!reader.matchesETagWithoutLessThan("jsp:text")) {
                err.jspError(start, "jsp.error.jsptext.badcontent");
            }
        }
    }

    /*
     * AllBody ::= ( '<%--' JSPCommentBody ) | ( '<%@' DirectiveBody ) | ( '<jsp:directive.'
     * XMLDirectiveBody ) | ( '<%!' DeclarationBody ) | ( '<jsp:declaration'
     * XMLDeclarationBody ) | ( '<%=' ExpressionBody ) | ( '<jsp:expression'
     * XMLExpressionBody ) | ( '${' ELExpressionBody ) | ( '<%' ScriptletBody ) | ( '<jsp:scriptlet'
     * XMLScriptletBody ) | ( '<jsp:text' XMLTemplateText ) | ( '<jsp:'
     * StandardAction ) | ( '<' CustomAction CustomActionBody ) | TemplateText
     */
    private void parseElements(Node parent) throws JasperException {
        if (scriptlessCount > 0) {
            // vc: ScriptlessBody
            // We must follow the ScriptlessBody production if one of
            // our parents is ScriptlessBody.
            parseElementsScriptless(parent);
            return;
        }

        start = reader.mark();
        if (reader.matches("<%--")) {
            parseComment(parent);
        } else if (reader.matches("<%@")) {
            parseDirective(parent);
        } else if (reader.matches("<jsp:directive.")) {
            parseXMLDirective(parent);
        } else if (reader.matches("<%!")) {
            parseDeclaration(parent);
        } else if (reader.matches("<jsp:declaration")) {
            parseXMLDeclaration(parent);
        } else if (reader.matches("<%=")) {
            parseExpression(parent);
        } else if (reader.matches("<jsp:expression")) {
            parseXMLExpression(parent);
        } else if (reader.matches("<%")) {
            parseScriptlet(parent);
        } else if (reader.matches("<jsp:scriptlet")) {
            parseXMLScriptlet(parent);
        } else if (reader.matches("<jsp:text")) {
            parseXMLTemplateText(parent);
        } else if (reader.matches("${")) {
            parseELExpression(parent, '$');
        } else if (reader.matches("#{")) {
            parseELExpression(parent, '#');
        } else if (reader.matches("<jsp:")) {
            parseStandardAction(parent);
        } else if (!parseCustomTag(parent)) {
            checkUnbalancedEndTag();
            parseTemplateText(parent);
        }
    }

    /*
     * ScriptlessBody ::= ( '<%--' JSPCommentBody ) | ( '<%@' DirectiveBody ) | ( '<jsp:directive.'
     * XMLDirectiveBody ) | ( '<%!' <TRANSLATION_ERROR> ) | ( '<jsp:declaration'
     * <TRANSLATION_ERROR> ) | ( '<%=' <TRANSLATION_ERROR> ) | ( '<jsp:expression'
     * <TRANSLATION_ERROR> ) | ( '<%' <TRANSLATION_ERROR> ) | ( '<jsp:scriptlet'
     * <TRANSLATION_ERROR> ) | ( '<jsp:text' XMLTemplateText ) | ( '${'
     * ELExpressionBody ) | ( '<jsp:' StandardAction ) | ( '<' CustomAction
     * CustomActionBody ) | TemplateText
     */
    private void parseElementsScriptless(Node parent) throws JasperException {
        // Keep track of how many scriptless nodes we've encountered
        // so we know whether our child nodes are forced scriptless
        scriptlessCount++;

        start = reader.mark();
        if (reader.matches("<%--")) {
            parseComment(parent);
        } else if (reader.matches("<%@")) {
            parseDirective(parent);
        } else if (reader.matches("<jsp:directive.")) {
            parseXMLDirective(parent);
        } else if (reader.matches("<%!")) {
            err.jspError(reader.mark(), "jsp.error.no.scriptlets");
        } else if (reader.matches("<jsp:declaration")) {
            err.jspError(reader.mark(), "jsp.error.no.scriptlets");
        } else if (reader.matches("<%=")) {
            err.jspError(reader.mark(), "jsp.error.no.scriptlets");
        } else if (reader.matches("<jsp:expression")) {
            err.jspError(reader.mark(), "jsp.error.no.scriptlets");
        } else if (reader.matches("<%")) {
            err.jspError(reader.mark(), "jsp.error.no.scriptlets");
        } else if (reader.matches("<jsp:scriptlet")) {
            err.jspError(reader.mark(), "jsp.error.no.scriptlets");
        } else if (reader.matches("<jsp:text")) {
            parseXMLTemplateText(parent);
        } else if (reader.matches("${")) {
            parseELExpression(parent, '$');
        } else if (reader.matches("#{")) {
            parseELExpression(parent, '#');
        } else if (reader.matches("<jsp:")) {
            parseStandardAction(parent);
        } else if (!parseCustomTag(parent)) {
            checkUnbalancedEndTag();
            parseTemplateText(parent);
        }

        scriptlessCount--;
    }

    /*
     * TemplateTextBody ::= ( '<%--' JSPCommentBody ) | ( '<%@' DirectiveBody ) | ( '<jsp:directive.'
     * XMLDirectiveBody ) | ( '<%!' <TRANSLATION_ERROR> ) | ( '<jsp:declaration'
     * <TRANSLATION_ERROR> ) | ( '<%=' <TRANSLATION_ERROR> ) | ( '<jsp:expression'
     * <TRANSLATION_ERROR> ) | ( '<%' <TRANSLATION_ERROR> ) | ( '<jsp:scriptlet'
     * <TRANSLATION_ERROR> ) | ( '<jsp:text' <TRANSLATION_ERROR> ) | ( '${'
     * <TRANSLATION_ERROR> ) | ( '<jsp:' <TRANSLATION_ERROR> ) | TemplateText
     */
    private void parseElementsTemplateText(Node parent) throws JasperException {
        start = reader.mark();
        if (reader.matches("<%--")) {
            parseComment(parent);
        } else if (reader.matches("<%@")) {
            parseDirective(parent);
        } else if (reader.matches("<jsp:directive.")) {
            parseXMLDirective(parent);
        } else if (reader.matches("<%!")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Declarations");
        } else if (reader.matches("<jsp:declaration")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Declarations");
        } else if (reader.matches("<%=")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Expressions");
        } else if (reader.matches("<jsp:expression")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Expressions");
        } else if (reader.matches("<%")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Scriptlets");
        } else if (reader.matches("<jsp:scriptlet")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Scriptlets");
        } else if (reader.matches("<jsp:text")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "&lt;jsp:text");
        } else if (reader.matches("${")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Expression language");
        } else if (reader.matches("#{")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Expression language");
        } else if (reader.matches("<jsp:")) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Standard actions");
        } else if (parseCustomTag(parent)) {
            err.jspError(reader.mark(), "jsp.error.not.in.template",
                    "Custom actions");
        } else {
            checkUnbalancedEndTag();
            parseTemplateText(parent);
        }
    }

    /*
     * Flag as error if an unbalanced end tag appears by itself.
     */
    private void checkUnbalancedEndTag() throws JasperException {

        if (!reader.matches("</")) {
            return;
        }

        // Check for unbalanced standard actions
        if (reader.matches("jsp:")) {
            err.jspError(start, "jsp.error.unbalanced.endtag", "jsp:");
        }

        // Check for unbalanced custom actions
        String tagName = reader.parseToken(false);
        int i = tagName.indexOf(':');
        if (i == -1 || pageInfo.getURI(tagName.substring(0, i)) == null) {
            reader.reset(start);
            return;
        }

        err.jspError(start, "jsp.error.unbalanced.endtag", tagName);
    }

    /**
     * TagDependentBody :=
     */
    private void parseTagDependentBody(Node parent, String tag)
            throws JasperException {
        Mark bodyStart = reader.mark();
        Mark bodyEnd = reader.skipUntilETag(tag);
        if (bodyEnd == null) {
            err.jspError(start, "jsp.error.unterminated", "&lt;" + tag);
        }
        new Node.TemplateText(reader.getText(bodyStart, bodyEnd), bodyStart,
                parent);
    }

    /*
     * Parses jsp:body action.
     */
    private void parseJspBody(Node parent, String bodyType)
            throws JasperException {
        Mark start = reader.mark();
        Node bodyNode = new Node.JspBody(start, parent);

        reader.skipSpaces();
        if (!reader.matches("/>")) {
            if (!reader.matches(">")) {
                err.jspError(start, "jsp.error.unterminated", "&lt;jsp:body");
            }
            parseBody(bodyNode, "jsp:body", bodyType);
        }
    }

    /*
     * Parse the body as JSP content. @param tag The name of the tag whose end
     * tag would terminate the body @param bodyType One of the TagInfo body
     * types
     */
    private void parseBody(Node parent, String tag, String bodyType)
            throws JasperException {
        if (bodyType.equalsIgnoreCase(TagInfo.BODY_CONTENT_TAG_DEPENDENT)) {
            parseTagDependentBody(parent, tag);
        } else if (bodyType.equalsIgnoreCase(TagInfo.BODY_CONTENT_EMPTY)) {
            if (!reader.matchesETag(tag)) {
                err.jspError(start, "jasper.error.emptybodycontent.nonempty",
                        tag);
            }
        } else if (bodyType == JAVAX_BODY_CONTENT_PLUGIN) {
            // (note the == since we won't recognize JAVAX_*
            // from outside this module).
            parsePluginTags(parent);
            if (!reader.matchesETag(tag)) {
                err.jspError(reader.mark(), "jsp.error.unterminated", "&lt;"
                        + tag);
            }
        } else if (bodyType.equalsIgnoreCase(TagInfo.BODY_CONTENT_JSP)
                || bodyType.equalsIgnoreCase(TagInfo.BODY_CONTENT_SCRIPTLESS)
                || (bodyType == JAVAX_BODY_CONTENT_PARAM)
                || (bodyType == JAVAX_BODY_CONTENT_TEMPLATE_TEXT)) {
            while (reader.hasMoreInput()) {
                if (reader.matchesETag(tag)) {
                    return;
                }

                // Check for nested jsp:body or jsp:attribute
                if (tag.equals("jsp:body") || tag.equals("jsp:attribute")) {
                    if (reader.matches("<jsp:attribute")) {
                        err.jspError(reader.mark(),
                                "jsp.error.nested.jspattribute");
                    } else if (reader.matches("<jsp:body")) {
                        err.jspError(reader.mark(), "jsp.error.nested.jspbody");
                    }
                }

                if (bodyType.equalsIgnoreCase(TagInfo.BODY_CONTENT_JSP)) {
                    parseElements(parent);
                } else if (bodyType
                        .equalsIgnoreCase(TagInfo.BODY_CONTENT_SCRIPTLESS)) {
                    parseElementsScriptless(parent);
                } else if (bodyType == JAVAX_BODY_CONTENT_PARAM) {
                    // (note the == since we won't recognize JAVAX_*
                    // from outside this module).
                    reader.skipSpaces();
                    parseParam(parent);
                } else if (bodyType == JAVAX_BODY_CONTENT_TEMPLATE_TEXT) {
                    parseElementsTemplateText(parent);
                }
            }
            err.jspError(start, "jsp.error.unterminated", "&lt;" + tag);
        } else {
            err.jspError(start, "jasper.error.bad.bodycontent.type");
        }
    }

    /*
     * Parses named attributes.
     */
    private void parseNamedAttributes(Node parent) throws JasperException {
        do {
            Mark start = reader.mark();
            Attributes attrs = parseAttributes();
            Node.NamedAttribute namedAttributeNode = new Node.NamedAttribute(
                    attrs, start, parent);

            reader.skipSpaces();
            if (!reader.matches("/>")) {
                if (!reader.matches(">")) {
                    err.jspError(start, "jsp.error.unterminated",
                            "&lt;jsp:attribute");
                }
                if (namedAttributeNode.isTrim()) {
                    reader.skipSpaces();
                }
                parseBody(namedAttributeNode, "jsp:attribute",
                        getAttributeBodyType(parent, at