Java tutorial
/* * Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package javax.imageio.metadata; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import org.w3c.dom.Attr; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.DOMException; import org.w3c.dom.NamedNodeMap; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.w3c.dom.TypeInfo; import org.w3c.dom.UserDataHandler; class IIODOMException extends DOMException { private static final long serialVersionUID = -4369510142067447468L; public IIODOMException(short code, String message) { super(code, message); } } class IIONamedNodeMap implements NamedNodeMap { List<? extends Node> nodes; public IIONamedNodeMap(List<? extends Node> nodes) { this.nodes = nodes; } public int getLength() { return nodes.size(); } public Node getNamedItem(String name) { Iterator<? extends Node> iter = nodes.iterator(); while (iter.hasNext()) { Node node = iter.next(); if (name.equals(node.getNodeName())) { return node; } } return null; } public Node item(int index) { Node node = nodes.get(index); return node; } public Node removeNamedItem(java.lang.String name) { throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, "This NamedNodeMap is read-only!"); } public Node setNamedItem(Node arg) { throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, "This NamedNodeMap is read-only!"); } /** * Equivalent to {@code getNamedItem(localName)}. */ public Node getNamedItemNS(String namespaceURI, String localName) { return getNamedItem(localName); } /** * Equivalent to {@code setNamedItem(arg)}. */ public Node setNamedItemNS(Node arg) { return setNamedItem(arg); } /** * Equivalent to {@code removeNamedItem(localName)}. */ public Node removeNamedItemNS(String namespaceURI, String localName) { return removeNamedItem(localName); } } class IIONodeList implements NodeList { List<? extends Node> nodes; public IIONodeList(List<? extends Node> nodes) { this.nodes = nodes; } public int getLength() { return nodes.size(); } public Node item(int index) { if (index < 0 || index >= nodes.size()) { return null; } return nodes.get(index); } } class IIOAttr extends IIOMetadataNode implements Attr { Element owner; String name; String value; public IIOAttr(Element owner, String name, String value) { this.owner = owner; this.name = name; this.value = value; } public String getName() { return name; } public String getNodeName() { return name; } public short getNodeType() { return ATTRIBUTE_NODE; } public boolean getSpecified() { return true; } public String getValue() { return value; } public String getNodeValue() { return value; } public void setValue(String value) { this.value = value; } public void setNodeValue(String value) { this.value = value; } public Element getOwnerElement() { return owner; } public void setOwnerElement(Element owner) { this.owner = owner; } /** This method is new in the DOM L3 for Attr interface. * Could throw DOMException here, but its probably OK * to always return false. One reason for this, is we have no good * way to document this exception, since this class, IIOAttr, * is not a public class. The rest of the methods that throw * DOMException are publically documented as such on IIOMetadataNode. * @return false */ public boolean isId() { return false; } } /** * A class representing a node in a meta-data tree, which implements * the {@link Element org.w3c.dom.Element} interface and additionally allows * for the storage of non-textual objects via the * {@code getUserObject} and {@code setUserObject} methods. * * <p> This class is not intended to be used for general XML * processing. In particular, {@code Element} nodes created * within the Image I/O API are not compatible with those created by * Sun's standard implementation of the {@code org.w3.dom} API. * In particular, the implementation is tuned for simple uses and may * not perform well for intensive processing. * * <p> Namespaces are ignored in this implementation. The terms "tag * name" and "node name" are always considered to be synonymous. * * <em>Note:</em> * The DOM Level 3 specification added a number of new methods to the * {@code Node}, {@code Element} and {@code Attr} interfaces that are not * of value to the {@code IIOMetadataNode} implementation or specification. * * Calling such methods on an {@code IIOMetadataNode}, or an {@code Attr} * instance returned from an {@code IIOMetadataNode} will result in a * {@code DOMException} being thrown. * * @see IIOMetadata#getAsTree * @see IIOMetadata#setFromTree * @see IIOMetadata#mergeTree * */ public class IIOMetadataNode implements Element, NodeList { /** * The name of the node as a {@code String}. */ private String nodeName = null; /** * The value of the node as a {@code String}. The Image I/O * API typically does not make use of the node value. */ private String nodeValue = null; /** * The {@code Object} value associated with this node. */ private Object userObject = null; /** * The parent node of this node, or {@code null} if this node * forms the root of its own tree. */ private IIOMetadataNode parent = null; /** * The number of child nodes. */ private int numChildren = 0; /** * The first (leftmost) child node of this node, or * {@code null} if this node is a leaf node. */ private IIOMetadataNode firstChild = null; /** * The last (rightmost) child node of this node, or * {@code null} if this node is a leaf node. */ private IIOMetadataNode lastChild = null; /** * The next (right) sibling node of this node, or * {@code null} if this node is its parent's last child node. */ private IIOMetadataNode nextSibling = null; /** * The previous (left) sibling node of this node, or * {@code null} if this node is its parent's first child node. */ private IIOMetadataNode previousSibling = null; /** * A {@code List} of {@code IIOAttr} nodes representing * attributes. */ private List<IIOAttr> attributes = new ArrayList<>(); /** * Constructs an empty {@code IIOMetadataNode}. */ public IIOMetadataNode() { } /** * Constructs an {@code IIOMetadataNode} with a given node * name. * * @param nodeName the name of the node, as a {@code String}. */ public IIOMetadataNode(String nodeName) { this.nodeName = nodeName; } /** * Check that the node is either {@code null} or an * {@code IIOMetadataNode}. * * @throws DOMException if {@code node} is not {@code null} and not an * instance of {@code IIOMetadataNode} */ private void checkNode(Node node) throws DOMException { if (node == null) { return; } if (!(node instanceof IIOMetadataNode)) { throw new IIODOMException(DOMException.WRONG_DOCUMENT_ERR, "Node not an IIOMetadataNode!"); } } // Methods from Node /** * Returns the node name associated with this node. * * @return the node name, as a {@code String}. */ public String getNodeName() { return nodeName; } /** * Returns the value associated with this node. * * @return the node value, as a {@code String}. */ public String getNodeValue() { return nodeValue; } /** * Sets the {@code String} value associated with this node. */ public void setNodeValue(String nodeValue) { this.nodeValue = nodeValue; } /** * Returns the node type, which is always * {@code ELEMENT_NODE}. * * @return the {@code short} value {@code ELEMENT_NODE}. */ public short getNodeType() { return ELEMENT_NODE; } /** * Returns the parent of this node. A {@code null} value * indicates that the node is the root of its own tree. To add a * node to an existing tree, use one of the * {@code insertBefore}, {@code replaceChild}, or * {@code appendChild} methods. * * @return the parent, as a {@code Node}. * * @see #insertBefore * @see #replaceChild * @see #appendChild */ public Node getParentNode() { return parent; } /** * Returns a {@code NodeList} that contains all children of this node. * If there are no children, this is a {@code NodeList} containing * no nodes. * * @return the children as a {@code NodeList} */ public NodeList getChildNodes() { return this; } /** * Returns the first child of this node, or {@code null} if * the node has no children. * * @return the first child, as a {@code Node}, or * {@code null} */ public Node getFirstChild() { return firstChild; } /** * Returns the last child of this node, or {@code null} if * the node has no children. * * @return the last child, as a {@code Node}, or * {@code null}. */ public Node getLastChild() { return lastChild; } /** * Returns the previous sibling of this node, or {@code null} * if this node has no previous sibling. * * @return the previous sibling, as a {@code Node}, or * {@code null}. */ public Node getPreviousSibling() { return previousSibling; } /** * Returns the next sibling of this node, or {@code null} if * the node has no next sibling. * * @return the next sibling, as a {@code Node}, or * {@code null}. */ public Node getNextSibling() { return nextSibling; } /** * Returns a {@code NamedNodeMap} containing the attributes of * this node. * * @return a {@code NamedNodeMap} containing the attributes of * this node. */ public NamedNodeMap getAttributes() { return new IIONamedNodeMap(attributes); } /** * Returns {@code null}, since {@code IIOMetadataNode}s * do not belong to any {@code Document}. * * @return {@code null}. */ public Document getOwnerDocument() { return null; } /** * Inserts the node {@code newChild} before the existing * child node {@code refChild}. If {@code refChild} is * {@code null}, insert {@code newChild} at the end of * the list of children. * * @param newChild the {@code Node} to insert. * @param refChild the reference {@code Node}. * * @return the node being inserted. * * @exception IllegalArgumentException if {@code newChild} is * {@code null}. */ public Node insertBefore(Node newChild, Node refChild) { if (newChild == null) { throw new IllegalArgumentException("newChild == null!"); } checkNode(newChild); checkNode(refChild); IIOMetadataNode newChildNode = (IIOMetadataNode) newChild; IIOMetadataNode refChildNode = (IIOMetadataNode) refChild; // Siblings, can be null. IIOMetadataNode previous = null; IIOMetadataNode next = null; if (refChild == null) { previous = this.lastChild; next = null; this.lastChild = newChildNode; } else { previous = refChildNode.previousSibling; next = refChildNode; } if (previous != null) { previous.nextSibling = newChildNode; } if (next != null) { next.previousSibling = newChildNode; } newChildNode.parent = this; newChildNode.previousSibling = previous; newChildNode.nextSibling = next; // N.B.: O.K. if refChild == null if (this.firstChild == refChildNode) { this.firstChild = newChildNode; } ++numChildren; return newChildNode; } /** * Replaces the child node {@code oldChild} with * {@code newChild} in the list of children, and returns the * {@code oldChild} node. * * @param newChild the {@code Node} to insert. * @param oldChild the {@code Node} to be replaced. * * @return the node replaced. * * @exception IllegalArgumentException if {@code newChild} is * {@code null}. */ public Node replaceChild(Node newChild, Node oldChild) { if (newChild == null) { throw new IllegalArgumentException("newChild == null!"); } checkNode(newChild); checkNode(oldChild); IIOMetadataNode newChildNode = (IIOMetadataNode) newChild; IIOMetadataNode oldChildNode = (IIOMetadataNode) oldChild; IIOMetadataNode previous = oldChildNode.previousSibling; IIOMetadataNode next = oldChildNode.nextSibling; if (previous != null) { previous.nextSibling = newChildNode; } if (next != null) { next.previousSibling = newChildNode; } newChildNode.parent = this; newChildNode.previousSibling = previous; newChildNode.nextSibling = next; if (firstChild == oldChildNode) { firstChild = newChildNode; } if (lastChild == oldChildNode) { lastChild = newChildNode; } oldChildNode.parent = null; oldChildNode.previousSibling = null; oldChildNode.nextSibling = null; return oldChildNode; } /** * Removes the child node indicated by {@code oldChild} from * the list of children, and returns it. * * @param oldChild the {@code Node} to be removed. * * @return the node removed. * * @exception IllegalArgumentException if {@code oldChild} is * {@code null}. */ public Node removeChild(Node oldChild) { if (oldChild == null) { throw new IllegalArgumentException("oldChild == null!"); } checkNode(oldChild); IIOMetadataNode oldChildNode = (IIOMetadataNode) oldChild; IIOMetadataNode previous = oldChildNode.previousSibling; IIOMetadataNode next = oldChildNode.nextSibling; if (previous != null) { previous.nextSibling = next; } if (next != null) { next.previousSibling = previous; } if (this.firstChild == oldChildNode) { this.firstChild = next; } if (this.lastChild == oldChildNode) { this.lastChild = previous; } oldChildNode.parent = null; oldChildNode.previousSibling = null; oldChildNode.nextSibling = null; --numChildren; return oldChildNode; } /** * Adds the node {@code newChild} to the end of the list of * children of this node. * * @param newChild the {@code Node} to insert. * * @return the node added. * * @exception IllegalArgumentException if {@code newChild} is * {@code null}. */ public Node appendChild(Node newChild) { if (newChild == null) { throw new IllegalArgumentException("newChild == null!"); } checkNode(newChild); // insertBefore will increment numChildren return insertBefore(newChild, null); } /** * Returns {@code true} if this node has child nodes. * * @return {@code true} if this node has children. */ public boolean hasChildNodes() { return numChildren > 0; } /** * Returns a duplicate of this node. The duplicate node has no * parent ({@code getParentNode} returns {@code null}). * If a shallow clone is being performed ({@code deep} is * {@code false}), the new node will not have any children or * siblings. If a deep clone is being performed, the new node * will form the root of a complete cloned subtree. * * @param deep if {@code true}, recursively clone the subtree * under the specified node; if {@code false}, clone only the * node itself. * * @return the duplicate node. */ public Node cloneNode(boolean deep) { IIOMetadataNode newNode = new IIOMetadataNode(this.nodeName); newNode.setUserObject(getUserObject()); // Attributes if (deep) { for (IIOMetadataNode child = firstChild; child != null; child = child.nextSibling) { newNode.appendChild(child.cloneNode(true)); } } return newNode; } /** * Does nothing, since {@code IIOMetadataNode}s do not * contain {@code Text} children. */ public void normalize() { } /** * Returns {@code false} since DOM features are not * supported. * * @return {@code false}. * * @param feature a {@code String}, which is ignored. * @param version a {@code String}, which is ignored. */ public boolean isSupported(String feature, String version) { return false; } /** * Returns {@code null}, since namespaces are not supported. */ public String getNamespaceURI() throws DOMException { return null; } /** * Returns {@code null}, since namespaces are not supported. * * @return {@code null}. * * @see #setPrefix */ public String getPrefix() { return null; } /** * Does nothing, since namespaces are not supported. * * @param prefix a {@code String}, which is ignored. * * @see #getPrefix */ public void setPrefix(String prefix) { } /** * Equivalent to {@code getNodeName}. * * @return the node name, as a {@code String}. */ public String getLocalName() { return nodeName; } // Methods from Element /** * Equivalent to {@code getNodeName}. * * @return the node name, as a {@code String} */ public String getTagName() { return nodeName; } /** * Retrieves an attribute value by name. * @param name The name of the attribute to retrieve. * @return The {@code Attr} value as a string, or the empty string * if that attribute does not have a specified or default value. */ public String getAttribute(String name) { Attr attr = getAttributeNode(name); if (attr == null) { return ""; } return attr.getValue(); } /** * Equivalent to {@code getAttribute(localName)}. * * @see #setAttributeNS */ public String getAttributeNS(String namespaceURI, String localName) { return getAttribute(localName); } public void setAttribute(String name, String value) { // Name must be valid unicode chars boolean valid = true; char[] chs = name.toCharArray(); for (int i = 0; i < chs.length; i++) { if (chs[i] >= 0xfffe) { valid = false; break; } } if (!valid) { throw new IIODOMException(DOMException.INVALID_CHARACTER_ERR, "Attribute name is illegal!"); } removeAttribute(name, false); attributes.add(new IIOAttr(this, name, value)); } /** * Equivalent to {@code setAttribute(qualifiedName, value)}. * * @see #getAttributeNS */ public void setAttributeNS(String namespaceURI, String qualifiedName, String value) { setAttribute(qualifiedName, value); } public void removeAttribute(String name) { removeAttribute(name, true); } private void removeAttribute(String name, boolean checkPresent) { int numAttributes = attributes.size(); for (int i = 0; i < numAttributes; i++) { IIOAttr attr = attributes.get(i); if (name.equals(attr.getName())) { attr.setOwnerElement(null); attributes.remove(i); return; } } // If we get here, the attribute doesn't exist if (checkPresent) { throw new IIODOMException(DOMException.NOT_FOUND_ERR, "No such attribute!"); } } /** * Equivalent to {@code removeAttribute(localName)}. */ public void removeAttributeNS(String namespaceURI, String localName) { removeAttribute(localName); } public Attr getAttributeNode(String name) { Node node = getAttributes().getNamedItem(name); return (Attr) node; } /** * Equivalent to {@code getAttributeNode(localName)}. * * @see #setAttributeNodeNS */ public Attr getAttributeNodeNS(String namespaceURI, String localName) { return getAttributeNode(localName); } public Attr setAttributeNode(Attr newAttr) throws DOMException { Element owner = newAttr.getOwnerElement(); if (owner != null) { if (owner == this) { return null; } else { throw new DOMException(DOMException.INUSE_ATTRIBUTE_ERR, "Attribute is already in use"); } } IIOAttr attr; if (newAttr instanceof IIOAttr) { attr = (IIOAttr) newAttr; attr.setOwnerElement(this); } else { attr = new IIOAttr(this, newAttr.getName(), newAttr.getValue()); } Attr oldAttr = getAttributeNode(attr.getName()); if (oldAttr != null) { removeAttributeNode(oldAttr); } attributes.add(attr); return oldAttr; } /** * Equivalent to {@code setAttributeNode(newAttr)}. * * @see #getAttributeNodeNS */ public Attr setAttributeNodeNS(Attr newAttr) { return setAttributeNode(newAttr); } public Attr removeAttributeNode(Attr oldAttr) { removeAttribute(oldAttr.getName()); return oldAttr; } public NodeList getElementsByTagName(String name) { List<Node> l = new ArrayList<>(); getElementsByTagName(name, l); return new IIONodeList(l); } private void getElementsByTagName(String name, List<Node> l) { if (nodeName.equals(name) || "*".equals(name)) { l.add(this); } Node child = getFirstChild(); while (child != null) { ((IIOMetadataNode) child).getElementsByTagName(name, l); child = child.getNextSibling(); } } /** * Equivalent to {@code getElementsByTagName(localName)}. */ public NodeList getElementsByTagNameNS(String namespaceURI, String localName) { return getElementsByTagName(localName); } public boolean hasAttributes() { return attributes.size() > 0; } public boolean hasAttribute(String name) { return getAttributeNode(name) != null; } /** * Equivalent to {@code hasAttribute(localName)}. */ public boolean hasAttributeNS(String namespaceURI, String localName) { return hasAttribute(localName); } // Methods from NodeList public int getLength() { return numChildren; } public Node item(int index) { if (index < 0) { return null; } Node child = getFirstChild(); while (child != null && index-- > 0) { child = child.getNextSibling(); } return child; } /** * Returns the {@code Object} value associated with this node. * * @return the user {@code Object}. * * @see #setUserObject */ public Object getUserObject() { return userObject; } /** * Sets the value associated with this node. * * @param userObject the user {@code Object}. * * @see #getUserObject */ public void setUserObject(Object userObject) { this.userObject = userObject; } // Start of dummy methods for DOM L3. /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public void setIdAttribute(String name, boolean isId) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public void setIdAttributeNS(String namespaceURI, String localName, boolean isId) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public void setIdAttributeNode(Attr idAttr, boolean isId) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public TypeInfo getSchemaTypeInfo() throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public Object setUserData(String key, Object data, UserDataHandler handler) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public Object getUserData(String key) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public Object getFeature(String feature, String version) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public boolean isSameNode(Node node) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public boolean isEqualNode(Node node) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public String lookupNamespaceURI(String prefix) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public boolean isDefaultNamespace(String namespaceURI) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public String lookupPrefix(String namespaceURI) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public String getTextContent() throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public void setTextContent(String textContent) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public short compareDocumentPosition(Node other) throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } /** * This DOM Level 3 method is not supported for {@code IIOMetadataNode} * and will throw a {@code DOMException}. * @throws DOMException always. */ public String getBaseURI() throws DOMException { throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Method not supported"); } //End of dummy methods for DOM L3. }