node.java

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        public ChildInfo getChildInfo() {
            return childInfo;
        }
    }

    /**
     * Represents a template text string
     */
    public static class TemplateText extends Node {

        private ArrayList extraSmap = null;

	public TemplateText(String text, Mark start, Node parent) {
	    super(null, null, text, start, parent);
	}

	public void accept(Visitor v) throws JasperException {
	    v.visit(this);
	}

        /**
         * Trim all whitespace from the left of the template text
         */
        public void ltrim() {
	    int index = 0;
            while ((index < text.length()) && (text.charAt(index) <= ' ')) {
		index++;
            }
            text = text.substring(index);
        }

        public void setText(String text) {
            this.text = text;
        }

        /**
         * Trim all whitespace from the right of the template text
         */
        public void rtrim() {
            int index = text.length();
            while( (index > 0) && (text.charAt(index-1) <= ' ') ) {
                index--;
            }
            text = text.substring(0, index);
        }

	/**
	 * Returns true if this template text contains whitespace only.
	 */
	public boolean isAllSpace() {
	    boolean isAllSpace = true;
	    for (int i=0; i<text.length(); i++) {
		if (!Character.isWhitespace(text.charAt(i))) {
		    isAllSpace = false;
		    break;
		}
	    }
	    return isAllSpace;
	}

        /**
         * Add a source to Java line mapping
         * @param srcLine The postion of the source line, relative to the line
         *        at the start of this node.  The corresponding java line is
         *        assumed to be consecutive, i.e. one more than the last.
         */
        public void addSmap(int srcLine) {
            if (extraSmap == null) {
                extraSmap = new ArrayList();
            }
            extraSmap.add(new Integer(srcLine));
        }

        public ArrayList getExtraSmap() {
            return extraSmap;
        }
    }

    /*********************************************************************
     * Auxillary classes used in Node
     */

    /**
     * Represents attributes that can be request time expressions.
     *
     * Can either be a plain attribute, an attribute that represents a
     * request time expression value, or a named attribute (specified using
     * the jsp:attribute standard action).
     */

    public static class JspAttribute {

	private String qName;
	private String uri;
	private String localName;
	private String value;
	private boolean expression;
	private boolean dynamic;
        private ELNode.Nodes el;

        // If true, this JspAttribute represents a <jsp:attribute>
        private boolean namedAttribute;
        // The node in the parse tree for the NamedAttribute
        private NamedAttribute namedAttributeNode;

        JspAttribute(String qName, String uri, String localName, String value,
		     boolean expr, ELNode.Nodes el, boolean dyn ) {
	    this.qName = qName;
	    this.uri = uri;
	    this.localName = localName;
	    this.value = value;
            this.namedAttributeNode = null;
	    this.expression = expr;
            this.el = el;
	    this.dynamic = dyn;
            this.namedAttribute = false;
	}

        /**
         * Use this constructor if the JspAttribute represents a
         * named attribute.  In this case, we have to store the nodes of
         * the body of the attribute.
         */
        JspAttribute(NamedAttribute na, boolean dyn) {
            this.qName = na.getName();
	    this.localName = na.getLocalName();
            this.value = null;
            this.namedAttributeNode = na;
            this.expression = false;
            this.el = null;
	    this.dynamic = dyn;
            this.namedAttribute = true;
        }

	/**
 	 * @return The name of the attribute
	 */
	public String getName() {
	    return qName;
	}

	/**
 	 * @return The local name of the attribute
	 */
	public String getLocalName() {
	    return localName;
	}

	/**
 	 * @return The namespace of the attribute, or null if in the default
	 * namespace
	 */
	public String getURI() {
	    return uri;
	}

	/**
         * Only makes sense if namedAttribute is false.
         *
         * @return the value for the attribute, or the expression string
         *         (stripped of "<%=", "%>", "%=", or "%"
         *          but containing "${" and "}" for EL expressions)
	 */
	public String getValue() {
	    return value;
	}

        /**
         * Only makes sense if namedAttribute is true.
         *
         * @return the nodes that evaluate to the body of this attribute.
         */
        public NamedAttribute getNamedAttributeNode() {
            return namedAttributeNode;
        }

	/**
         * @return true if the value represents a traditional rtexprvalue
	 */
	public boolean isExpression() {
	    return expression;
	}

        /**
         * @return true if the value represents a NamedAttribute value.
         */
        public boolean isNamedAttribute() {
            return namedAttribute;
        }

        /**
         * @return true if the value represents an expression that should
         * be fed to the expression interpreter
         * @return false for string literals or rtexprvalues that should
         * not be interpreted or reevaluated
         */
        public boolean isELInterpreterInput() {
            return el != null;
        }

	/**
	 * @return true if the value is a string literal known at translation
	 * time.
	 */
	public boolean isLiteral() {
	    return !expression && (el != null) && !namedAttribute;
	}

	/**
	 * XXX
	 */
	public boolean isDynamic() {
	    return dynamic;
	}

	public ELNode.Nodes getEL() {
	    return el;
	}
    }

    /**
     * An ordered list of Node, used to represent the body of an element, or
     * a jsp page of jsp document.
     */
    public static class Nodes {

	private List list;
	private Node.Root root;		// null if this is not a page
	private boolean generatedInBuffer;

	public Nodes() {
	    list = new Vector();
	}

	public Nodes(Node.Root root) {
	    this.root = root;
	    list = new Vector();
	    list.add(root);
	}

	/**
	 * Appends a node to the list
	 * @param n The node to add
	 */
	public void add(Node n) {
	    list.add(n);
	    root = null;
	}

	/**
	 * Removes the given node from the list.
	 * @param n The node to be removed
	 */
	public void remove(Node n) {
	    list.remove(n);
	}

	/**
	 * Visit the nodes in the list with the supplied visitor
	 * @param v The visitor used
	 */
	public void visit(Visitor v) throws JasperException {
	    Iterator iter = list.iterator();
	    while (iter.hasNext()) {
		Node n = (Node) iter.next();
		n.accept(v);
	    }
	}

	public int size() {
	    return list.size();
	}

	public Node getNode(int index) {
	    Node n = null;
	    try {
		n = (Node) list.get(index);
	    } catch (ArrayIndexOutOfBoundsException e) {
	    }
	    return n;
	}
	
	public Node.Root getRoot() {
	    return root;
	}

	public boolean isGeneratedInBuffer() {
	    return generatedInBuffer;
	}

	public void setGeneratedInBuffer(boolean g) {
	    generatedInBuffer = g;
	}
    }

    /**
     * A visitor class for visiting the node.  This class also provides the
     * default action (i.e. nop) for each of the child class of the Node.
     * An actual visitor should extend this class and supply the visit
     * method for the nodes that it cares.
     */
    public static class Visitor {

	/**
	 * This method provides a place to put actions that are common to
	 * all nodes. Override this in the child visitor class if need to.
	 */
	protected void doVisit(Node n) throws JasperException {
	}

	/**
	 * Visit the body of a node, using the current visitor
	 */
	protected void visitBody(Node n) throws JasperException {
	    if (n.getBody() != null) {
		n.getBody().visit(this);
	    }
	}

	public void visit(Root n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(JspRoot n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(PageDirective n) throws JasperException {
	    doVisit(n);
	}

	public void visit(TagDirective n) throws JasperException {
	    doVisit(n);
	}

	public void visit(IncludeDirective n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(TaglibDirective n) throws JasperException {
	    doVisit(n);
	}

	public void visit(AttributeDirective n) throws JasperException {
	    doVisit(n);
	}

	public void visit(VariableDirective n) throws JasperException {
	    doVisit(n);
	}

	public void visit(Comment n) throws JasperException {
	    doVisit(n);
	}

	public void visit(Declaration n) throws JasperException {
	    doVisit(n);
	}

	public void visit(Expression n) throws JasperException {
	    doVisit(n);
	}

	public void visit(Scriptlet n) throws JasperException {
	    doVisit(n);
	}

        public void visit(ELExpression n) throws JasperException {
            doVisit(n);
        }

	public void visit(IncludeAction n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(ForwardAction n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(GetProperty n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(SetProperty n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(ParamAction n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(ParamsAction n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(FallBackAction n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(UseBean n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(PlugIn n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(CustomTag n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(UninterpretedTag n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(JspElement n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

	public void visit(JspText n) throws JasperException {
	    doVisit(n);
	    visitBody(n);
	}

        public void visit(NamedAttribute n) throws JasperException {
            doVisit(n);
            visitBody(n);
        }

        public void visit(JspBody n) throws JasperException {
            doVisit(n);
            visitBody(n);
        }

        public void visit(InvokeAction n) throws JasperException {
            doVisit(n);
            visitBody(n);
        }

        public void visit(DoBodyAction n) throws JasperException {
            doVisit(n);
            visitBody(n);
        }

	public void visit(TemplateText n) throws JasperException {
	    doVisit(n);
	}

	public void visit(JspOutput n) throws JasperException {
	    doVisit(n);
	}

	public void visit(AttributeGenerator n) throws JasperException {
	    doVisit(n);
	}
    }
}