parser.java

业界著名的tomcat服务器的最新6.0的源代码。

    /*
     * ExpressionBody ::= (Char* - (char* '%>')) '%>'
     */
    private void parseExpression(Node parent) throws JasperException {
        start = reader.mark();
        Mark stop = reader.skipUntil("%>");
        if (stop == null) {
            err.jspError(start, "jsp.error.unterminated", "<%=");
        }

        new Node.Expression(parseScriptText(reader.getText(start, stop)),
                start, parent);
    }

    /*
     * XMLExpressionBody ::= ( S? '/>' ) | ( S? '>' (Char* - (char* '<'))
     * CDSect?)* ETag ) | <TRANSLATION_ERROR>
     */
    private void parseXMLExpression(Node parent) throws JasperException {
        reader.skipSpaces();
        if (!reader.matches("/>")) {
            if (!reader.matches(">")) {
                err.jspError(start, "jsp.error.unterminated",
                        "&lt;jsp:expression&gt;");
            }
            Mark stop;
            String text;
            while (true) {
                start = reader.mark();
                stop = reader.skipUntil("<");
                if (stop == null) {
                    err.jspError(start, "jsp.error.unterminated",
                            "&lt;jsp:expression&gt;");
                }
                text = parseScriptText(reader.getText(start, stop));
                new Node.Expression(text, start, parent);
                if (reader.matches("![CDATA[")) {
                    start = reader.mark();
                    stop = reader.skipUntil("]]>");
                    if (stop == null) {
                        err.jspError(start, "jsp.error.unterminated", "CDATA");
                    }
                    text = parseScriptText(reader.getText(start, stop));
                    new Node.Expression(text, start, parent);
                } else {
                    break;
                }
            }
            if (!reader.matchesETagWithoutLessThan("jsp:expression")) {
                err.jspError(start, "jsp.error.unterminated",
                        "&lt;jsp:expression&gt;");
            }
        }
    }

    /*
     * ELExpressionBody (following "${" to first unquoted "}") // XXX add formal
     * production and confirm implementation against it, // once it's decided
     */
    private void parseELExpression(Node parent, char type) throws JasperException {
        start = reader.mark();
        Mark last = null;
        boolean singleQuoted = false, doubleQuoted = false;
        int currentChar;
        do {
            // XXX could move this logic to JspReader
            last = reader.mark(); // XXX somewhat wasteful
            currentChar = reader.nextChar();
            if (currentChar == '\\' && (singleQuoted || doubleQuoted)) {
                // skip character following '\' within quotes
                reader.nextChar();
                currentChar = reader.nextChar();
            }
            if (currentChar == -1)
                err.jspError(start, "jsp.error.unterminated", type + "{");
            if (currentChar == '"')
                doubleQuoted = !doubleQuoted;
            if (currentChar == '\'')
                singleQuoted = !singleQuoted;
        } while (currentChar != '}' || (singleQuoted || doubleQuoted));

        new Node.ELExpression(type, reader.getText(start, last), start, parent);
    }

    /*
     * ScriptletBody ::= (Char* - (char* '%>')) '%>'
     */
    private void parseScriptlet(Node parent) throws JasperException {
        start = reader.mark();
        Mark stop = reader.skipUntil("%>");
        if (stop == null) {
            err.jspError(start, "jsp.error.unterminated", "&lt;%");
        }

        new Node.Scriptlet(parseScriptText(reader.getText(start, stop)), start,
                parent);
    }

    /*
     * XMLScriptletBody ::= ( S? '/>' ) | ( S? '>' (Char* - (char* '<'))
     * CDSect?)* ETag ) | <TRANSLATION_ERROR>
     */
    private void parseXMLScriptlet(Node parent) throws JasperException {
        reader.skipSpaces();
        if (!reader.matches("/>")) {
            if (!reader.matches(">")) {
                err.jspError(start, "jsp.error.unterminated",
                        "&lt;jsp:scriptlet&gt;");
            }
            Mark stop;
            String text;
            while (true) {
                start = reader.mark();
                stop = reader.skipUntil("<");
                if (stop == null) {
                    err.jspError(start, "jsp.error.unterminated",
                            "&lt;jsp:scriptlet&gt;");
                }
                text = parseScriptText(reader.getText(start, stop));
                new Node.Scriptlet(text, start, parent);
                if (reader.matches("![CDATA[")) {
                    start = reader.mark();
                    stop = reader.skipUntil("]]>");
                    if (stop == null) {
                        err.jspError(start, "jsp.error.unterminated", "CDATA");
                    }
                    text = parseScriptText(reader.getText(start, stop));
                    new Node.Scriptlet(text, start, parent);
                } else {
                    break;
                }
            }

            if (!reader.matchesETagWithoutLessThan("jsp:scriptlet")) {
                err.jspError(start, "jsp.error.unterminated",
                        "&lt;jsp:scriptlet&gt;");
            }
        }
    }

    /**
     * Param ::= '<jsp:param' S Attributes S? EmptyBody S?
     */
    private void parseParam(Node parent) throws JasperException {
        if (!reader.matches("<jsp:param")) {
            err.jspError(reader.mark(), "jsp.error.paramexpected");
        }
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node paramActionNode = new Node.ParamAction(attrs, start, parent);

        parseEmptyBody(paramActionNode, "jsp:param");

        reader.skipSpaces();
    }

    /*
     * For Include: StdActionContent ::= Attributes ParamBody
     * 
     * ParamBody ::= EmptyBody | ( '>' S? ( '<jsp:attribute' NamedAttributes )? '<jsp:body'
     * (JspBodyParam | <TRANSLATION_ERROR> ) S? ETag ) | ( '>' S? Param* ETag )
     * 
     * EmptyBody ::= '/>' | ( '>' ETag ) | ( '>' S? '<jsp:attribute'
     * NamedAttributes ETag )
     * 
     * JspBodyParam ::= S? '>' Param* '</jsp:body>'
     */
    private void parseInclude(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node includeNode = new Node.IncludeAction(attrs, start, parent);

        parseOptionalBody(includeNode, "jsp:include", JAVAX_BODY_CONTENT_PARAM);
    }

    /*
     * For Forward: StdActionContent ::= Attributes ParamBody
     */
    private void parseForward(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node forwardNode = new Node.ForwardAction(attrs, start, parent);

        parseOptionalBody(forwardNode, "jsp:forward", JAVAX_BODY_CONTENT_PARAM);
    }

    private void parseInvoke(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node invokeNode = new Node.InvokeAction(attrs, start, parent);

        parseEmptyBody(invokeNode, "jsp:invoke");
    }

    private void parseDoBody(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node doBodyNode = new Node.DoBodyAction(attrs, start, parent);

        parseEmptyBody(doBodyNode, "jsp:doBody");
    }

    private void parseElement(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node elementNode = new Node.JspElement(attrs, start, parent);

        parseOptionalBody(elementNode, "jsp:element", TagInfo.BODY_CONTENT_JSP);
    }

    /*
     * For GetProperty: StdActionContent ::= Attributes EmptyBody
     */
    private void parseGetProperty(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node getPropertyNode = new Node.GetProperty(attrs, start, parent);

        parseOptionalBody(getPropertyNode, "jsp:getProperty",
                TagInfo.BODY_CONTENT_EMPTY);
    }

    /*
     * For SetProperty: StdActionContent ::= Attributes EmptyBody
     */
    private void parseSetProperty(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node setPropertyNode = new Node.SetProperty(attrs, start, parent);

        parseOptionalBody(setPropertyNode, "jsp:setProperty",
                TagInfo.BODY_CONTENT_EMPTY);
    }

    /*
     * EmptyBody ::= '/>' | ( '>' ETag ) | ( '>' S? '<jsp:attribute'
     * NamedAttributes ETag )
     */
    private void parseEmptyBody(Node parent, String tag) throws JasperException {
        if (reader.matches("/>")) {
            // Done
        } else if (reader.matches(">")) {
            if (reader.matchesETag(tag)) {
                // Done
            } else if (reader.matchesOptionalSpacesFollowedBy("<jsp:attribute")) {
                // Parse the one or more named attribute nodes
                parseNamedAttributes(parent);
                if (!reader.matchesETag(tag)) {
                    // Body not allowed
                    err.jspError(reader.mark(),
                            "jsp.error.jspbody.emptybody.only", "&lt;" + tag);
                }
            } else {
                err.jspError(reader.mark(), "jsp.error.jspbody.emptybody.only",
                        "&lt;" + tag);
            }
        } else {
            err.jspError(reader.mark(), "jsp.error.unterminated", "&lt;" + tag);
        }
    }

    /*
     * For UseBean: StdActionContent ::= Attributes OptionalBody
     */
    private void parseUseBean(Node parent) throws JasperException {
        Attributes attrs = parseAttributes();
        reader.skipSpaces();

        Node useBeanNode = new Node.UseBean(attrs, start, parent);

        parseOptionalBody(useBeanNode, "jsp:useBean", TagInfo.BODY_CONTENT_JSP);
    }

    /*
     * Parses OptionalBody, but also reused to parse bodies for plugin and param
     * since the syntax is identical (the only thing that differs substantially
     * is how to process the body, and thus we accept the body type as a
     * parameter).
     * 
     * OptionalBody ::= EmptyBody | ActionBody
     * 
     * ScriptlessOptionalBody ::= EmptyBody | ScriptlessActionBody
     * 
     * TagDependentOptionalBody ::= EmptyBody | TagDependentActionBody
     * 
     * EmptyBody ::= '/>' | ( '>' ETag ) | ( '>' S? '<jsp:attribute'
     * NamedAttributes ETag )
     * 
     * ActionBody ::= JspAttributeAndBody | ( '>' Body ETag )
     * 
     * ScriptlessActionBody ::= JspAttributeAndBody | ( '>' ScriptlessBody ETag )
     * 
     * TagDependentActionBody ::= JspAttributeAndBody | ( '>' TagDependentBody
     * ETag )
     * 
     */
    private void parseOptionalBody(Node parent, String tag, String bodyType)
            throws JasperException {
        if (reader.matches("/>")) {
            // EmptyBody
            return;
        }

        if (!reader.matches(">")) {
            err.jspError(reader.mark(), "jsp.error.unterminated", "&lt;" + tag);
        }

        if (reader.matchesETag(tag)) {
            // EmptyBody
            return;
        }

        if (!parseJspAttributeAndBody(parent, tag, bodyType)) {
            // Must be ( '>' # Body ETag )
            parseBody(parent, tag, bodyType);
        }
    }

    /**
     * Attempts to parse 'JspAttributeAndBody' production. Returns true if it
     * matched, or false if not. Assumes EmptyBody is okay as well.
     * 
     * JspAttributeAndBody ::= ( '>' # S? ( '<jsp:attribute' NamedAttributes )? '<jsp:body' (
     * JspBodyBody | <TRANSLATION_ERROR> ) S? ETag )
     */
    private boolean parseJspAttributeAndBody(Node parent, String tag,
            String bodyType) throws JasperException {
        boolean result = false;

        if (reader.matchesOptionalSpacesFollowedBy("<jsp:attribute")) {
            // May be an EmptyBody, depending on whether