domutil.java

jsr170接口的java实现。是个apache的开源项目。

    }

    /**
     * Returns true if the specified node matches the required names. Note, that
     * that tests return true if the required name is <code>null</code>.
     *
     * @param node
     * @param requiredLocalName
     * @param requiredNamespace
     * @return true if local name and namespace match the corresponding properties
     * of the given DOM node.
     */
    public static boolean matches(Node node, String requiredLocalName, Namespace requiredNamespace) {
        if (node == null) {
            return false;
        }
        boolean matchingNamespace = matchingNamespace(node, requiredNamespace);
        return matchingNamespace && matchingLocalName(node, requiredLocalName);
    }

    /**
     * @param node
     * @param requiredNamespace
     * @return true if the required namespace is <code>null</code> or matches
     * the namespace of the specified node.
     */
    private static boolean matchingNamespace(Node node, Namespace requiredNamespace) {
        if (requiredNamespace == null) {
            return true;
        } else {
            return requiredNamespace.isSame(node.getNamespaceURI());
        }
    }

    /**
     * @param node
     * @param requiredLocalName
     * @return true if the required local name is <code>null</code> or if the
     * nodes local name matches.
     */
    private static boolean matchingLocalName(Node node, String requiredLocalName) {
        if (requiredLocalName == null) {
            return true;
        } else {
            String localName = node.getLocalName();
            return requiredLocalName.equals(localName);
        }
    }

    /**
     * @param node
     * @return true if the specified node is either an element or Text or CDATA
     */
    private static boolean isAcceptedNode(Node node) {
        return isElement(node) || isText(node);
    }

    /**
     * @param node
     * @return true if the given node is of type element.
     */
    static boolean isElement(Node node) {
        return node.getNodeType() == Node.ELEMENT_NODE;
    }

    /**
     * @param node
     * @return true if the given node is of type text or CDATA.
     */
    static boolean isText(Node node) {
        int ntype = node.getNodeType();
        return ntype == Node.TEXT_NODE || ntype == Node.CDATA_SECTION_NODE;
    }

    //----------------------------------------------------< factory methods >---
    /**
     * Create a new DOM element with the specified local name and namespace.
     *
     * @param factory
     * @param localName
     * @param namespace
     * @return a new DOM element
     * @see Document#createElement(String)
     * @see Document#createElementNS(String, String)
     */
    public static Element createElement(Document factory, String localName, Namespace namespace) {
        if (namespace != null) {
            return factory.createElementNS(namespace.getURI(), getPrefixedName(localName, namespace));
        } else {
            return factory.createElement(localName);
        }
    }

    /**
     * Create a new DOM element with the specified local name and namespace and
     * add the specified text as Text node to it.
     *
     * @param factory
     * @param localName
     * @param namespace
     * @param text
     * @return a new DOM element
     * @see Document#createElement(String)
     * @see Document#createElementNS(String, String)
     * @see Document#createTextNode(String)
     * @see Node#appendChild(org.w3c.dom.Node)
     */
    public static Element createElement(Document factory, String localName, Namespace namespace, String text) {
        Element elem = createElement(factory, localName, namespace);
        setText(elem, text);
        return elem;
    }

    /**
     * Add a new child element with the given local name and namespace to the
     * specified parent.
     *
     * @param parent
     * @param localName
     * @param namespace
     * @return the new element that was attached to the given parent.
     */
    public static Element addChildElement(Element parent, String localName, Namespace namespace) {
        Element elem = createElement(parent.getOwnerDocument(), localName, namespace);
        parent.appendChild(elem);
        return elem;
    }

    /**
     * Add a new child element with the given local name and namespace to the
     * specified parent.
     *
     * @param parent
     * @param localName
     * @param namespace
     * @return the new element that was attached to the given parent.
     */
    public static Element addChildElement(Node parent, String localName, Namespace namespace) {
        Document doc = parent.getOwnerDocument();
        if (parent instanceof Document) {
            doc = (Document) parent;
        }
        Element elem = createElement(doc, localName, namespace);
        parent.appendChild(elem);
        return elem;
    }

    /**
     * Add a new child element with the given local name and namespace to the
     * specified parent. The specified text is added as Text node to the created
     * child element.
     *
     * @param parent
     * @param localName
     * @param namespace
     * @param text
     * @return child element that was added to the specified parent
     * @see Document#createElement(String)
     * @see Document#createElementNS(String, String)
     * @see Document#createTextNode(String)
     * @see Node#appendChild(org.w3c.dom.Node)
     */
    public static Element addChildElement(Element parent, String localName, Namespace namespace, String text) {
        Element elem = createElement(parent.getOwnerDocument(), localName, namespace, text);
        parent.appendChild(elem);
        return elem;
    }

    /**
     * Create a new text node and add it as child to the given element.
     *
     * @param element
     * @param text
     */
    public static void setText(Element element, String text) {
        if (text == null || "".equals(text)) {
            // ignore null/empty string text
            return;
        }
        Text txt = element.getOwnerDocument().createTextNode(text);
        element.appendChild(txt);
    }

    /**
     * Add an attribute node to the given element.
     *
     * @param element
     * @param attrLocalName
     * @param attrNamespace
     * @param attrValue
     */
    public static void setAttribute(Element element, String attrLocalName, Namespace attrNamespace, String attrValue) {
        if (attrNamespace == null) {
            Attr attr = element.getOwnerDocument().createAttribute(attrLocalName);
            attr.setValue(attrValue);
            element.setAttributeNode(attr);
        } else {
            Attr attr = element.getOwnerDocument().createAttributeNS(attrNamespace.getURI(), getPrefixedName(attrLocalName, attrNamespace));
            attr.setValue(attrValue);
            element.setAttributeNodeNS(attr);
        }
    }

    /**
     * Adds a namespace attribute on the given element.
     *
     * @param element
     * @param prefix
     * @param uri
     */
    public static void setNamespaceAttribute(Element element, String prefix, String uri) {
        setAttribute(element, prefix, Namespace.XMLNS_NAMESPACE, uri);
    }

    /**
     * Converts the given timeout (long value defining the number of milli-
     * second until timeout is reached) to its Xml representation as defined
     * by RTF 2518.<br>
     * Note, that {@link DavConstants#INFINITE_TIMEOUT} is not represented by the String
     * {@link DavConstants#TIMEOUT_INFINITE 'Infinite'} defined by RFC 2518, due to a known
     * issue with Microsoft Office that opens the document "read only" and
     * never unlocks the resource if the timeout is missing or 'Infinite'.
     *
     * @param timeout number of milli-seconds until timeout is reached.
     * @return 'timeout' Xml element
     */
    public static Element timeoutToXml(long timeout, Document factory) {
        String expString = "Second-"+ timeout/1000;;
        Element exp = createElement(factory, DavConstants.XML_TIMEOUT, DavConstants.NAMESPACE, expString);
        return exp;
    }

    /**
     * Returns the Xml representation of a boolean isDeep, where false
     * presents a depth value of '0', true a depth value of 'infinity'.
     *
     * @param isDeep
     * @return Xml representation
     */
    public static Element depthToXml(boolean isDeep, Document factory) {
        return depthToXml(isDeep? "infinity" : "0", factory);
    }

    /**
     * Returns the Xml representation of a depth String. Webdav defines the
     * following valid values for depths: 0, 1, infinity
     *
     * @param depth
     * @return 'deep' JDOM element
     */
    public static Element depthToXml(String depth, Document factory) {
        Element dElem = createElement(factory, DavConstants.XML_DEPTH, DavConstants.NAMESPACE, depth);
        return dElem;
    }

    /**
     * Builds a 'DAV:href' Xml element from the given href. Please note, that
     * the path present in the given String should be properly
     * {@link org.apache.jackrabbit.util.Text#escapePath(String) escaped} in order to prevent problems with
     * WebDAV clients.
     *
     * @param href String representing the text of the 'href' Xml element
     * @param factory the Document used as factory
     * @return Xml representation of a 'href' according to RFC 2518.
     */
    public static Element hrefToXml(String href, Document factory) {
        return createElement(factory, DavConstants.XML_HREF, DavConstants.NAMESPACE, href);
    }

    /**
     * Return a qualified name of a DOM node consisting of "{" + namespace uri + "}"
     * + localName. If the specified namespace is <code>null</code> or represents
     * the empty namespace, the local name is returned.
     *
     * @param localName
     * @param namespace
     * @return
     */
    public static String getQualifiedName(String localName, Namespace namespace) {
        if (namespace == null || namespace.equals(Namespace.EMPTY_NAMESPACE)) {
            return localName;
        }
        StringBuffer b = new StringBuffer("{");
        b.append(namespace.getURI()).append("}");
        b.append(localName);
        return b.toString();
    }

    /**
     * Return the prefixed name of a DOM node consisting of
     * namespace prefix + ":" + local name. If the specified namespace is <code>null</code>
     * or contains an empty prefix, the local name is returned.<br>
     * NOTE, that this is the value to be used for the 'qualified Name' parameter
     * expected with the namespace sensitive factory methods.
     *
     * @param localName
     * @param namespace
     * @return qualified name consisting of prefix, ':' and local name.
     * @see Document#createAttributeNS(String, String)
     * @see Document#createElementNS(String, String)
     */
    public static String getPrefixedName(String localName, Namespace namespace) {
        if (namespace == null
            || Namespace.EMPTY_NAMESPACE.equals(namespace) 
            || Namespace.EMPTY_NAMESPACE.getPrefix().equals(namespace.getPrefix())) {
            return localName;
        }
        StringBuffer buf = new StringBuffer(namespace.getPrefix());
        buf.append(":");
        buf.append(localName);
        return buf.toString();
    }
}