pagedataimpl.java

业界著名的tomcat服务器的最新6.0的源代码。

	public void visit(Node.UseBean n) throws JasperException {
	    appendTag(n);
	}
	
	public void visit(Node.PlugIn n) throws JasperException {
	    appendTag(n);
	}

        public void visit(Node.NamedAttribute n) throws JasperException {
            appendTag(n);
        }
        
        public void visit(Node.JspBody n) throws JasperException {
            appendTag(n);
        }

	public void visit(Node.CustomTag n) throws JasperException {
	    boolean resetDefaultNSSave = resetDefaultNS;
	    appendTag(n, resetDefaultNS);
	    resetDefaultNS = resetDefaultNSSave;
	}

	public void visit(Node.UninterpretedTag n) throws JasperException {
	    boolean resetDefaultNSSave = resetDefaultNS;
	    appendTag(n, resetDefaultNS);
	    resetDefaultNS = resetDefaultNSSave;
	}

	public void visit(Node.JspText n) throws JasperException {
	    appendTag(n);
	}

	public void visit(Node.DoBodyAction n) throws JasperException {
	    appendTag(n);
	}

        public void visit(Node.InvokeAction n) throws JasperException {
	    appendTag(n);
	}

	public void visit(Node.TagDirective n) throws JasperException {
	    appendTagDirective(n);
	}

	public void visit(Node.AttributeDirective n) throws JasperException {
	    appendTag(n);
	}

	public void visit(Node.VariableDirective n) throws JasperException {
	    appendTag(n);
	}
        
	public void visit(Node.TemplateText n) throws JasperException {
	    /*
	     * If the template text came from a JSP page written in JSP syntax,
	     * create a jsp:text element for it (JSP 5.3.2).
	     */
	    appendText(n.getText(), !n.getRoot().isXmlSyntax());
	}

	/*
	 * Appends the given tag, including its body, to the XML view.
	 */
	private void appendTag(Node n) throws JasperException {
	    appendTag(n, false);
	}

	/*
	 * Appends the given tag, including its body, to the XML view,
	 * and optionally reset default namespace to "", if none specified.
	 */
	private void appendTag(Node n, boolean addDefaultNS)
		throws JasperException {

	    Node.Nodes body = n.getBody();
	    String text = n.getText();

	    buf.append("<").append(n.getQName());
	    buf.append("\n");

	    printAttributes(n, addDefaultNS);
	    buf.append("  ").append(jspIdPrefix).append(":id").append("=\"");
	    buf.append(jspId++).append("\"\n");

	    if (ROOT_ACTION.equals(n.getLocalName()) || body != null
		        || text != null) {
		buf.append(">\n");
		if (ROOT_ACTION.equals(n.getLocalName())) {
		    if (compiler.getCompilationContext().isTagFile()) {
			appendTagDirective();
		    } else {
			appendPageDirective();
		    }
		}
		if (body != null) {
		    body.visit(this);
		} else {
		    appendText(text, false);
		}
		buf.append("</" + n.getQName() + ">\n");
	    } else {
		buf.append("/>\n");
	    }
	}

	/*
	 * Appends the page directive with the given attributes to the XML
	 * view.
	 *
	 * Since the import attribute of the page directive is the only page
	 * attribute that is allowed to appear multiple times within the same
	 * document, and since XML allows only single-value attributes,
	 * the values of multiple import attributes must be combined into one,
	 * separated by comma.
	 *
	 * If the given page directive contains just 'contentType' and/or
	 * 'pageEncoding' attributes, we ignore it, as we've already appended
	 * a page directive containing just these two attributes.
	 */
	private void appendPageDirective(Node.PageDirective n) {
	    boolean append = false;
	    Attributes attrs = n.getAttributes();
	    int len = (attrs == null) ? 0 : attrs.getLength();
	    for (int i=0; i<len; i++) {
		String attrName = attrs.getQName(i);
		if (!"pageEncoding".equals(attrName)
		        && !"contentType".equals(attrName)) {
		    append = true;
		    break;
		}
	    }
	    if (!append) {
		return;
	    }

	    buf.append("<").append(n.getQName());
	    buf.append("\n");

	    // append jsp:id
	    buf.append("  ").append(jspIdPrefix).append(":id").append("=\"");
	    buf.append(jspId++).append("\"\n");

	    // append remaining attributes
	    for (int i=0; i<len; i++) {
		String attrName = attrs.getQName(i);
		if ("import".equals(attrName) || "contentType".equals(attrName)
		        || "pageEncoding".equals(attrName)) {
		    /*
		     * Page directive's 'import' attribute is considered
		     * further down, and its 'pageEncoding' and 'contentType'
		     * attributes are ignored, since we've already appended
		     * a new page directive containing just these two
		     * attributes
		     */
		    continue;
		}
		String value = attrs.getValue(i);
		buf.append("  ").append(attrName).append("=\"");
		buf.append(JspUtil.getExprInXml(value)).append("\"\n");
	    }
	    if (n.getImports().size() > 0) {
		// Concatenate names of imported classes/packages
		boolean first = true;
		ListIterator iter = n.getImports().listIterator();
		while (iter.hasNext()) {
		    if (first) {
			first = false;
			buf.append("  import=\"");
		    } else {
			buf.append(",");
		    }
		    buf.append(JspUtil.getExprInXml((String) iter.next()));
		}
		buf.append("\"\n");
	    }
	    buf.append("/>\n");
	}

	/*
	 * Appends a page directive with 'pageEncoding' and 'contentType'
	 * attributes.
	 *
	 * The value of the 'pageEncoding' attribute is hard-coded
	 * to UTF-8, whereas the value of the 'contentType' attribute, which
	 * is identical to what the container will pass to
	 * ServletResponse.setContentType(), is derived from the pageInfo.
	 */
	private void appendPageDirective() {
	    buf.append("<").append(JSP_PAGE_DIRECTIVE_ACTION);
	    buf.append("\n");

	    // append jsp:id
	    buf.append("  ").append(jspIdPrefix).append(":id").append("=\"");
	    buf.append(jspId++).append("\"\n");
	    buf.append("  ").append("pageEncoding").append("=\"UTF-8\"\n");
	    buf.append("  ").append("contentType").append("=\"");
	    buf.append(compiler.getPageInfo().getContentType()).append("\"\n");
	    buf.append("/>\n");	    
	}

	/*
	 * Appends the tag directive with the given attributes to the XML
	 * view.
	 *
	 * If the given tag directive contains just a 'pageEncoding'
	 * attributes, we ignore it, as we've already appended
	 * a tag directive containing just this attributes.
	 */
	private void appendTagDirective(Node.TagDirective n)
	        throws JasperException {

	    boolean append = false;
	    Attributes attrs = n.getAttributes();
	    int len = (attrs == null) ? 0 : attrs.getLength();
	    for (int i=0; i<len; i++) {
		String attrName = attrs.getQName(i);
		if (!"pageEncoding".equals(attrName)) {
		    append = true;
		    break;
		}
	    }
	    if (!append) {
		return;
	    }

	    appendTag(n);
	}

	/*
	 * Appends a tag directive containing a single 'pageEncoding'
	 * attribute whose value is hard-coded to UTF-8.
	 */
	private void appendTagDirective() {
	    buf.append("<").append(JSP_TAG_DIRECTIVE_ACTION);
	    buf.append("\n");

	    // append jsp:id
	    buf.append("  ").append(jspIdPrefix).append(":id").append("=\"");
	    buf.append(jspId++).append("\"\n");
	    buf.append("  ").append("pageEncoding").append("=\"UTF-8\"\n");
	    buf.append("/>\n");	    
	}

	private void appendText(String text, boolean createJspTextElement) {
	    if (createJspTextElement) {
		buf.append("<").append(JSP_TEXT_ACTION);
		buf.append("\n");

		// append jsp:id
		buf.append("  ").append(jspIdPrefix).append(":id").append("=\"");
		buf.append(jspId++).append("\"\n");
		buf.append(">\n");

		appendCDATA(text);
		buf.append(JSP_TEXT_ACTION_END);
		buf.append("\n");
	    } else {
		appendCDATA(text);
	    }
	}
	
	/*
	 * Appends the given text as a CDATA section to the XML view, unless
	 * the text has already been marked as CDATA.
	 */
	private void appendCDATA(String text) {
	    buf.append(CDATA_START_SECTION);
	    buf.append(escapeCDATA(text));
	    buf.append(CDATA_END_SECTION);
	}

	/*
	 * Escapes any occurrences of "]]>" (by replacing them with "]]&gt;")
	 * within the given text, so it can be included in a CDATA section.
	 */
	private String escapeCDATA(String text) {
            if( text==null ) return "";
	    int len = text.length();
	    CharArrayWriter result = new CharArrayWriter(len);
	    for (int i=0; i<len; i++) {
		if (((i+2) < len)
		        && (text.charAt(i) == ']')
		        && (text.charAt(i+1) == ']')
		        && (text.charAt(i+2) == '>')) {
		    // match found
		    result.write(']');
		    result.write(']');
		    result.write('&');
		    result.write('g');
		    result.write('t');
		    result.write(';');
		    i += 2;
		} else {
		    result.write(text.charAt(i));
		}
	    }
	    return result.toString();
	}

	/*
	 * Appends the attributes of the given Node to the XML view.
	 */
	private void printAttributes(Node n, boolean addDefaultNS) {

	    /*
	     * Append "xmlns" attributes that represent tag libraries
	     */
	    Attributes attrs = n.getTaglibAttributes();
	    int len = (attrs == null) ? 0 : attrs.getLength();
	    for (int i=0; i<len; i++) {
		String name = attrs.getQName(i);
		String value = attrs.getValue(i);
		buf.append("  ").append(name).append("=\"").append(value).append("\"\n");
	    }

	    /*
	     * Append "xmlns" attributes that do not represent tag libraries
	     */
	    attrs = n.getNonTaglibXmlnsAttributes();
	    len = (attrs == null) ? 0 : attrs.getLength();
	    boolean defaultNSSeen = false;
	    for (int i=0; i<len; i++) {
		String name = attrs.getQName(i);
		String value = attrs.getValue(i);
		buf.append("  ").append(name).append("=\"").append(value).append("\"\n");
		defaultNSSeen |= "xmlns".equals(name);
	    }
	    if (addDefaultNS && !defaultNSSeen) {
		buf.append("  xmlns=\"\"\n");
	    }
	    resetDefaultNS = false;

	    /*
	     * Append all other attributes
	     */
	    attrs = n.getAttributes();
	    len = (attrs == null) ? 0 : attrs.getLength();
	    for (int i=0; i<len; i++) {
		String name = attrs.getQName(i);
		String value = attrs.getValue(i);
		buf.append("  ").append(name).append("=\"");
		buf.append(JspUtil.getExprInXml(value)).append("\"\n");
	    }
	}

	/*
	 * Appends XML prolog with encoding declaration.
	 */
	private void appendXmlProlog() {
	    buf.append("<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n");
	}
    }
}