node.java

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	    super(qName, localName, attrs, nonTaglibXmlnsAttrs, taglibAttrs,
		  start, parent);

	    this.uri = uri;
	    this.prefix = prefix;
	    this.tagFileInfo = tagFileInfo;
	    this.tagInfo = tagFileInfo.getTagInfo();
	    this.customNestingLevel = makeCustomNestingLevel();
            this.childInfo = new ChildInfo();

	    this.implementsIterationTag = false;
	    this.implementsBodyTag = false;
	    this.implementsTryCatchFinally = false;
	    this.implementsSimpleTag = true;
	    this.implementsDynamicAttributes = tagInfo.hasDynamicAttributes();
	}

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

	/**
	 * @return The URI namespace that this custom action belongs to
	 */
	public String getURI() {
	    return this.uri;
	}

	/**
	 * @return The tag prefix
	 */
	public String getPrefix() {
	    return prefix;
	}

	public void setJspAttributes(JspAttribute[] jspAttrs) {
	    this.jspAttrs = jspAttrs;
	}

	public JspAttribute[] getJspAttributes() {
	    return jspAttrs;
	}
        
        public ChildInfo getChildInfo() {
            return childInfo;
        }
	
	public void setTagData(TagData tagData) {
	    this.tagData = tagData;
	    this.varInfos = tagInfo.getVariableInfo(tagData);
	    if (this.varInfos == null) {
		this.varInfos = ZERO_VARIABLE_INFO;
	    }
	}

	public TagData getTagData() {
	    return tagData;
	}

	public void setTagHandlerPoolName(String s) {
	    tagHandlerPoolName = s;
	}

	public String getTagHandlerPoolName() {
	    return tagHandlerPoolName;
	}

	public TagInfo getTagInfo() {
	    return tagInfo;
	}

	public TagFileInfo getTagFileInfo() {
	    return tagFileInfo;
	}

	/*
	 * @return true if this custom action is supported by a tag file,
	 * false otherwise
	 */
	public boolean isTagFile() {
	    return tagFileInfo != null;
	}

	public Class getTagHandlerClass() {
	    return tagHandlerClass;
	}

	public void setTagHandlerClass(Class hc) {
	    tagHandlerClass = hc;
	}

	public boolean implementsIterationTag() {
	    return implementsIterationTag;
	}

	public boolean implementsBodyTag() {
	    return implementsBodyTag;
	}

	public boolean implementsTryCatchFinally() {
	    return implementsTryCatchFinally;
	}

	public boolean implementsSimpleTag() {
	    return implementsSimpleTag;
	}

	public boolean implementsDynamicAttributes() {
	    return implementsDynamicAttributes;
	}

	public TagVariableInfo[] getTagVariableInfos() {
	    return tagInfo.getTagVariableInfos();
 	}
 
	public VariableInfo[] getVariableInfos() {
	    return varInfos;
	}

	public void setCustomTagParent(Node.CustomTag n) {
	    this.customTagParent = n;
	}

	public Node.CustomTag getCustomTagParent() {
	    return this.customTagParent;
	}

	public void setNumCount(Integer count) {
	    this.numCount = count;
	}

	public Integer getNumCount() {
	    return this.numCount;
	}

	public void setScriptingVars(Vector vec, int scope) {
	    switch (scope) {
	    case VariableInfo.AT_BEGIN:
		this.atBeginScriptingVars = vec;
		break;
	    case VariableInfo.AT_END:
		this.atEndScriptingVars = vec;
		break;
	    case VariableInfo.NESTED:
		this.nestedScriptingVars = vec;
		break;
	    }
	}

	/*
	 * Gets the scripting variables for the given scope that need to be
	 * declared.
	 */
	public Vector getScriptingVars(int scope) {
	    Vector vec = null;

	    switch (scope) {
	    case VariableInfo.AT_BEGIN:
		vec = this.atBeginScriptingVars;
		break;
	    case VariableInfo.AT_END:
		vec = this.atEndScriptingVars;
		break;
	    case VariableInfo.NESTED:
		vec = this.nestedScriptingVars;
		break;
	    }

	    return vec;
	}

	/*
	 * Gets this custom tag's custom nesting level, which is given as
	 * the number of times this custom tag is nested inside itself.
	 */
	public int getCustomNestingLevel() {
	    return customNestingLevel;
	}

        /**
         * Checks to see if the attribute of the given name is of type
	 * JspFragment.
         */
        public boolean checkIfAttributeIsJspFragment( String name ) {
            boolean result = false;

	    TagAttributeInfo[] attributes = tagInfo.getAttributes();
	    for (int i = 0; i < attributes.length; i++) {
		if (attributes[i].getName().equals(name) &&
		            attributes[i].isFragment()) {
		    result = true;
		    break;
		}
	    }
            
            return result;
        }

	public void setUseTagPlugin(boolean use) {
	    useTagPlugin = use;
	}

	public boolean useTagPlugin() {
	    return useTagPlugin;
	}

	public void setTagPluginContext(TagPluginContext tagPluginContext) {
	    this.tagPluginContext = tagPluginContext;
	}

	public TagPluginContext getTagPluginContext() {
	    return tagPluginContext;
	}

	public void setAtSTag(Nodes sTag) {
	    atSTag = sTag;
	}

	public Nodes getAtSTag() {
	    return atSTag;
	}
        
	public void setAtETag(Nodes eTag) {
	    atETag = eTag;
	}

	public Nodes getAtETag() {
	    return atETag;
	}
        
	/*
	 * Computes this custom tag's custom nesting level, which corresponds
	 * to the number of times this custom tag is nested inside itself.
	 *
	 * Example:
	 * 
	 *  <g:h>
	 *    <a:b> -- nesting level 0
	 *      <c:d>
	 *        <e:f>
	 *          <a:b> -- nesting level 1
	 *            <a:b> -- nesting level 2
	 *            </a:b>
	 *          </a:b>
	 *          <a:b> -- nesting level 1
	 *          </a:b>
	 *        </e:f>
	 *      </c:d>
	 *    </a:b>
	 *  </g:h>
	 * 
	 * @return Custom tag's nesting level
	 */
	private int makeCustomNestingLevel() {
	    int n = 0;
	    Node p = parent;
	    while (p != null) {
		if ((p instanceof Node.CustomTag)
		        && qName.equals(((Node.CustomTag) p).qName)) {
		    n++;
		}
		p = p.parent;
	    }
	    return n;
	}

	/**
	 * Returns true if this custom action has an empty body, and false
	 * otherwise.
	 *
	 * A custom action is considered to have an empty body if the 
	 * following holds true:
	 * - getBody() returns null, or
	 * - all immediate children are jsp:attribute actions, or
	 * - the action's jsp:body is empty.
	 */
	 public boolean hasEmptyBody() {
	     boolean hasEmptyBody = true;
	     Nodes nodes = getBody();
	     if (nodes != null) {
		 int numChildNodes = nodes.size();
		 for (int i=0; i<numChildNodes; i++) {
		     Node n = nodes.getNode(i);
		     if (!(n instanceof NamedAttribute)) {
			 if (n instanceof JspBody) {
			     hasEmptyBody = (n.getBody() == null);
			 } else {
			     hasEmptyBody = false;
			 }
			 break;
		     }
		 }
	     }

	     return hasEmptyBody;
	 }
    }

    /**
     * Used as a placeholder for the evaluation code of a custom action
     * attribute (used by the tag plugin machinery only).
     */
    public static class AttributeGenerator extends Node {
	String name;	// name of the attribute
	CustomTag tag;	// The tag this attribute belongs to

	public AttributeGenerator(Mark start, String name, CustomTag tag) {
	    super(start, null);
	    this.name = name;
	    this.tag = tag;
	}

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

	public String getName() {
	    return name;
	}

	public CustomTag getTag() {
	    return tag;
	}
    }

    /**
     * Represents the body of a &lt;jsp:text&gt; element
     */
    public static class JspText extends Node {

	public JspText(String qName, Attributes nonTaglibXmlnsAttrs,
		       Attributes taglibAttrs, Mark start, Node parent) {
	    super(qName, TEXT_ACTION, null, nonTaglibXmlnsAttrs, taglibAttrs,
		  start, parent);
	}

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

    /**
     * Represents a Named Attribute (&lt;jsp:attribute&gt;)
     */
    public static class NamedAttribute extends Node {

        // A unique temporary variable name suitable for code generation
        private String temporaryVariableName;

        // True if this node is to be trimmed, or false otherwise
        private boolean trim = true;
        
        private ChildInfo childInfo;
	private String name;
	private String localName;
	private String prefix;

        public NamedAttribute(Attributes attrs, Mark start, Node parent) {
	    this(JSP_ATTRIBUTE_ACTION, attrs, null, null, start, parent);
	}

        public NamedAttribute(String qName, Attributes attrs,
			      Attributes nonTaglibXmlnsAttrs,
			      Attributes taglibAttrs,
			      Mark start, Node parent) {

            super(qName, ATTRIBUTE_ACTION, attrs, nonTaglibXmlnsAttrs,
		  taglibAttrs, start, parent);
            temporaryVariableName = JspUtil.nextTemporaryVariableName();
            if( "false".equals( this.getAttributeValue( "trim" ) ) ) {
                // (if null or true, leave default of true)
                trim = false;
            }
            childInfo = new ChildInfo();
	    name = this.getAttributeValue("name");
            if (name != null) {
                // Mandatary attribute "name" will be checked in Validator
	        localName = name;
	        int index = name.indexOf(':');
	        if (index != -1) {
		    prefix = name.substring(0, index);
		    localName = name.substring(index+1);
                }
	    }
        }

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

        public String getName() {
            return this.name;
        }

        public String getLocalName() {
            return this.localName;
        }

        public String getPrefix() {
            return this.prefix;
        }
        
        public ChildInfo getChildInfo() {
            return this.childInfo;
        }

        public boolean isTrim() {
            return trim;
        }

        /**
         * @return A unique temporary variable name to store the result in.
         *      (this probably could go elsewhere, but it's convenient here)
         */
        public String getTemporaryVariableName() {
            return temporaryVariableName;
        }

	/*
	 * Get the attribute value from this named attribute (<jsp:attribute>).
	 * Since this method is only for attributes that are not rtexpr,
	 * we can assume the body of the jsp:attribute is a template text.
	 */
	public String getText() {

	    class AttributeVisitor extends Visitor {
		String attrValue = null;
		public void visit(TemplateText txt) {
		    attrValue = new String(txt.getText());
		}
		
		public String getAttrValue() {
		    return attrValue;
		}
	    }

	    // According to JSP 2.0, if the body of the <jsp:attribute>
	    // action is empty, it is equivalent of specifying "" as the value
	    // of the attribute.
	    String text = "";
	    if (getBody() != null) {
		AttributeVisitor attributeVisitor = new AttributeVisitor();
		try {
		    getBody().visit(attributeVisitor);
		} catch (JasperException e) {
		}
		text = attributeVisitor.getAttrValue();
	    }
	    
	    return text;
	}
    }

    /**
     * Represents a JspBody node (&lt;jsp:body&gt;)
     */
    public static class JspBody extends Node {

        private ChildInfo childInfo;

        public JspBody(Mark start, Node parent) {
            this(JSP_BODY_ACTION, null, null, start, parent);
        }

        public JspBody(String qName, Attributes nonTaglibXmlnsAttrs,
		       Attributes taglibAttrs, Mark start, Node parent) {
            super(qName, BODY_ACTION, null, nonTaglibXmlnsAttrs, taglibAttrs,
		  start, parent);
            this.childInfo = new ChildInfo();
        }

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