Java tutorial
/* * 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. */ /* * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file and, per its terms, should not be removed: * * Copyright (c) 2004 World Wide Web Consortium, * * (Massachusetts Institute of Technology, European Research Consortium for * Informatics and Mathematics, Keio University). All Rights Reserved. This * work is distributed under the W3C(r) Software License [1] 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. * * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231 */ package org.w3c.dom.ls; import org.w3c.dom.DOMConfiguration; import org.w3c.dom.Node; import org.w3c.dom.DOMException; /** * A <code>LSSerializer</code> provides an API for serializing (writing) a * DOM document out into XML. The XML data is written to a string or an * output stream. Any changes or fixups made during the serialization affect * only the serialized data. The <code>Document</code> object and its * children are never altered by the serialization operation. * <p> During serialization of XML data, namespace fixup is done as defined in * [<a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>DOM Level 3 Core</a>] * , Appendix B. [<a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113'>DOM Level 2 Core</a>] * allows empty strings as a real namespace URI. If the * <code>namespaceURI</code> of a <code>Node</code> is empty string, the * serialization will treat them as <code>null</code>, ignoring the prefix * if any. * <p> <code>LSSerializer</code> accepts any node type for serialization. For * nodes of type <code>Document</code> or <code>Entity</code>, well-formed * XML will be created when possible (well-formedness is guaranteed if the * document or entity comes from a parse operation and is unchanged since it * was created). The serialized output for these node types is either as a * XML document or an External XML Entity, respectively, and is acceptable * input for an XML parser. For all other types of nodes the serialized form * is implementation dependent. * <p>Within a <code>Document</code>, <code>DocumentFragment</code>, or * <code>Entity</code> being serialized, <code>Nodes</code> are processed as * follows * <ul> * <li> <code>Document</code> nodes are written, including the XML * declaration (unless the parameter "xml-declaration" is set to * <code>false</code>) and a DTD subset, if one exists in the DOM. Writing a * <code>Document</code> node serializes the entire document. * </li> * <li> * <code>Entity</code> nodes, when written directly by * <code>LSSerializer.write</code>, outputs the entity expansion but no * namespace fixup is done. The resulting output will be valid as an * external entity. * </li> * <li> If the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-entities'>entities</a>" * is set to <code>true</code>, <code>EntityReference</code> nodes are * serialized as an entity reference of the form " * <code>&entityName;</code>" in the output. Child nodes (the expansion) * of the entity reference are ignored. If the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-entities'>entities</a>" * is set to <code>false</code>, only the children of the entity reference * are serialized. <code>EntityReference</code> nodes with no children (no * corresponding <code>Entity</code> node or the corresponding * <code>Entity</code> nodes have no children) are always serialized. * </li> * <li> * <code>CDATAsections</code> containing content characters that cannot be * represented in the specified output encoding are handled according to the * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-split-cdata-sections'>split-cdata-sections</a>" * parameter. If the parameter is set to <code>true</code>, * <code>CDATAsections</code> are split, and the unrepresentable characters * are serialized as numeric character references in ordinary content. The * exact position and number of splits is not specified. If the parameter * is set to <code>false</code>, unrepresentable characters in a * <code>CDATAsection</code> are reported as * <code>"wf-invalid-character"</code> errors if the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-well-formed'>well-formed</a>" * is set to <code>true</code>. The error is not recoverable - there is no * mechanism for supplying alternative characters and continuing with the * serialization. * </li> * <li> <code>DocumentFragment</code> nodes are serialized by * serializing the children of the document fragment in the order they * appear in the document fragment. * </li> * <li> All other node types (Element, Text, * etc.) are serialized to their corresponding XML source form. * </li> * </ul> * <p ><b>Note:</b> The serialization of a <code>Node</code> does not always * generate a well-formed XML document, i.e. a <code>LSParser</code> might * throw fatal errors when parsing the resulting serialization. * <p> Within the character data of a document (outside of markup), any * characters that cannot be represented directly are replaced with * character references. Occurrences of '<' and '&' are replaced by * the predefined entities &lt; and &amp;. The other predefined * entities (&gt;, &apos;, and &quot;) might not be used, except * where needed (e.g. using &gt; in cases such as ']]>'). Any * characters that cannot be represented directly in the output character * encoding are serialized as numeric character references (and since * character encoding standards commonly use hexadecimal representations of * characters, using the hexadecimal representation when serializing * character references is encouraged). * <p> To allow attribute values to contain both single and double quotes, the * apostrophe or single-quote character (') may be represented as * "&apos;", and the double-quote character (") as "&quot;". New * line characters and other characters that cannot be represented directly * in attribute values in the output character encoding are serialized as a * numeric character reference. * <p> Within markup, but outside of attributes, any occurrence of a character * that cannot be represented in the output character encoding is reported * as a <code>DOMError</code> fatal error. An example would be serializing * the element <LaCañada/> with <code>encoding="us-ascii"</code>. * This will result with a generation of a <code>DOMError</code> * "wf-invalid-character-in-node-name" (as proposed in * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-well-formed'>well-formed</a>"). * <p> When requested by setting the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-normalize-characters'>normalize-characters</a>" * on <code>LSSerializer</code> to true, character normalization is * performed according to the definition of * <a href='http://www.w3.org/TR/2004/REC-xml11-20040204/#dt-fullnorm'>fully * normalized</a> characters included in appendix E of * [<a href='http://www.w3.org/TR/2004/REC-xml11-20040204/'>XML 1.1</a>] on all * data to be serialized, both markup and character data. The character * normalization process affects only the data as it is being written; it * does not alter the DOM's view of the document after serialization has * completed. * <p> Implementations are required to support the encodings "UTF-8", * "UTF-16", "UTF-16BE", and "UTF-16LE" to guarantee that data is * serializable in all encodings that are required to be supported by all * XML parsers. When the encoding is UTF-8, whether or not a byte order mark * is serialized, or if the output is big-endian or little-endian, is * implementation dependent. When the encoding is UTF-16, whether or not the * output is big-endian or little-endian is implementation dependent, but a * Byte Order Mark must be generated for non-character outputs, such as * <code>LSOutput.byteStream</code> or <code>LSOutput.systemId</code>. If * the Byte Order Mark is not generated, a "byte-order-mark-needed" warning * is reported. When the encoding is UTF-16LE or UTF-16BE, the output is * big-endian (UTF-16BE) or little-endian (UTF-16LE) and the Byte Order Mark * is not be generated. In all cases, the encoding declaration, if * generated, will correspond to the encoding used during the serialization * (e.g. <code>encoding="UTF-16"</code> will appear if UTF-16 was * requested). * <p> Namespaces are fixed up during serialization, the serialization process * will verify that namespace declarations, namespace prefixes and the * namespace URI associated with elements and attributes are consistent. If * inconsistencies are found, the serialized form of the document will be * altered to remove them. The method used for doing the namespace fixup * while serializing a document is the algorithm defined in Appendix B.1, * "Namespace normalization", of * [<a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>DOM Level 3 Core</a>] * . * <p> While serializing a document, the parameter "discard-default-content" * controls whether or not non-specified data is serialized. * <p> While serializing, errors and warnings are reported to the application * through the error handler (<code>LSSerializer.domConfig</code>'s * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-error-handler'>error-handler</a>" * parameter). This specification does in no way try to define all possible * errors and warnings that can occur while serializing a DOM node, but some * common error and warning cases are defined. The types ( * <code>DOMError.type</code>) of errors and warnings defined by this * specification are: * <dl> * <dt><code>"no-output-specified" [fatal]</code></dt> * <dd> Raised when * writing to a <code>LSOutput</code> if no output is specified in the * <code>LSOutput</code>. </dd> * <dt> * <code>"unbound-prefix-in-entity-reference" [fatal]</code> </dt> * <dd> Raised if the * configuration parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-namespaces'>namespaces</a>" * is set to <code>true</code> and an entity whose replacement text * contains unbound namespace prefixes is referenced in a location where * there are no bindings for the namespace prefixes. </dd> * <dt> * <code>"unsupported-encoding" [fatal]</code></dt> * <dd> Raised if an unsupported * encoding is encountered. </dd> * </dl> * <p> In addition to raising the defined errors and warnings, implementations * are expected to raise implementation specific errors and warnings for any * other error and warning cases such as IO errors (file not found, * permission denied,...) and so on. * <p>See also the * <a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-LS-20040407'> Document Object Model (DOM) Level 3 Load and Save Specification</a>. * * @since 1.5 */ public interface LSSerializer { /** * The <code>DOMConfiguration</code> object used by the * <code>LSSerializer</code> when serializing a DOM node. * <br> In addition to the parameters recognized by the * <a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#DOMConfiguration'>DOMConfiguration</a> * interface defined in * [<a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>DOM Level 3 Core</a>] * , the <code>DOMConfiguration</code> objects for * <code>LSSerializer</code> adds, or modifies, the following * parameters: * <dl> * <dt><code>"canonical-form"</code></dt> * <dd> * <dl> * <dt><code>true</code></dt> * <dd>[<em>optional</em>] Writes the document according to the rules specified in * [<a href='http://www.w3.org/TR/2001/REC-xml-c14n-20010315'>Canonical XML</a>]. * In addition to the behavior described in * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-canonical-form'>canonical-form</a>" * [<a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>DOM Level 3 Core</a>] * , setting this parameter to <code>true</code> will set the parameters * "format-pretty-print", "discard-default-content", and "xml-declaration * ", to <code>false</code>. Setting one of those parameters to * <code>true</code> will set this parameter to <code>false</code>. * Serializing an XML 1.1 document when "canonical-form" is * <code>true</code> will generate a fatal error. </dd> * <dt><code>false</code></dt> * <dd>[<em>required</em>] (<em>default</em>) Do not canonicalize the output. </dd> * </dl></dd> * <dt><code>"discard-default-content"</code></dt> * <dd> * <dl> * <dt> * <code>true</code></dt> * <dd>[<em>required</em>] (<em>default</em>) Use the <code>Attr.specified</code> attribute to decide what attributes * should be discarded. Note that some implementations might use * whatever information available to the implementation (i.e. XML * schema, DTD, the <code>Attr.specified</code> attribute, and so on) to * determine what attributes and content to discard if this parameter is * set to <code>true</code>. </dd> * <dt><code>false</code></dt> * <dd>[<em>required</em>]Keep all attributes and all content.</dd> * </dl></dd> * <dt><code>"format-pretty-print"</code></dt> * <dd> * <dl> * <dt> * <code>true</code></dt> * <dd>[<em>optional</em>] Formatting the output by adding whitespace to produce a pretty-printed, * indented, human-readable form. The exact form of the transformations * is not specified by this specification. Pretty-printing changes the * content of the document and may affect the validity of the document, * validating implementations should preserve validity. </dd> * <dt> * <code>false</code></dt> * <dd>[<em>required</em>] (<em>default</em>) Don't pretty-print the result. </dd> * </dl></dd> * <dt> * <code>"ignore-unknown-character-denormalizations"</code> </dt> * <dd> * <dl> * <dt> * <code>true</code></dt> * <dd>[<em>required</em>] (<em>default</em>) If, while verifying full normalization when * [<a href='http://www.w3.org/TR/2004/REC-xml11-20040204/'>XML 1.1</a>] is * supported, a character is encountered for which the normalization * properties cannot be determined, then raise a * <code>"unknown-character-denormalization"</code> warning (instead of * raising an error, if this parameter is not set) and ignore any * possible denormalizations caused by these characters. </dd> * <dt> * <code>false</code></dt> * <dd>[<em>optional</em>] Report a fatal error if a character is encountered for which the * processor cannot determine the normalization properties. </dd> * </dl></dd> * <dt> * <code>"normalize-characters"</code></dt> * <dd> This parameter is equivalent to * the one defined by <code>DOMConfiguration</code> in * [<a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>DOM Level 3 Core</a>] * . Unlike in the Core, the default value for this parameter is * <code>true</code>. While DOM implementations are not required to * support <a href='http://www.w3.org/TR/2004/REC-xml11-20040204/#dt-fullnorm'>fully * normalizing</a> the characters in the document according to appendix E of * [<a href='http://www.w3.org/TR/2004/REC-xml11-20040204/'>XML 1.1</a>], this * parameter must be activated by default if supported. </dd> * <dt> * <code>"xml-declaration"</code></dt> * <dd> * <dl> * <dt><code>true</code></dt> * <dd>[<em>required</em>] (<em>default</em>) If a <code>Document</code>, * <code>Element</code>, or <code>Entity</code> * node is serialized, the XML declaration, or text declaration, should * be included. The version (<code>Document.xmlVersion</code> if the * document is a Level 3 document and the version is non-null, otherwise * use the value "1.0"), and the output encoding (see * <code>LSSerializer.write</code> for details on how to find the output * encoding) are specified in the serialized XML declaration. </dd> * <dt> * <code>false</code></dt> * <dd>[<em>required</em>] Do not serialize the XML and text declarations. Report a * <code>"xml-declaration-needed"</code> warning if this will cause * problems (i.e. the serialized data is of an XML version other than * [<a href='http://www.w3.org/TR/2004/REC-xml-20040204'>XML 1.0</a>], or an * encoding would be needed to be able to re-parse the serialized data). </dd> * </dl></dd> * </dl> */ public DOMConfiguration getDomConfig(); /** * The end-of-line sequence of characters to be used in the XML being * written out. Any string is supported, but XML treats only a certain * set of characters sequence as end-of-line (See section 2.11, * "End-of-Line Handling" in [<a href='http://www.w3.org/TR/2004/REC-xml-20040204'>XML 1.0</a>], * if the serialized content is XML 1.0 or section 2.11, "End-of-Line Handling" * in [<a href='http://www.w3.org/TR/2004/REC-xml11-20040204/'>XML 1.1</a>], if the * serialized content is XML 1.1). Using other character sequences than * the recommended ones can result in a document that is either not * serializable or not well-formed). * <br> On retrieval, the default value of this attribute is the * implementation specific default end-of-line sequence. DOM * implementations should choose the default to match the usual * convention for text files in the environment being used. * Implementations must choose a default sequence that matches one of * those allowed by XML 1.0 or XML 1.1, depending on the serialized * content. Setting this attribute to <code>null</code> will reset its * value to the default value. * <br> */ public String getNewLine(); /** * The end-of-line sequence of characters to be used in the XML being * written out. Any string is supported, but XML treats only a certain * set of characters sequence as end-of-line (See section 2.11, * "End-of-Line Handling" in [<a href='http://www.w3.org/TR/2004/REC-xml-20040204'>XML 1.0</a>], * if the serialized content is XML 1.0 or section 2.11, "End-of-Line Handling" * in [<a href='http://www.w3.org/TR/2004/REC-xml11-20040204/'>XML 1.1</a>], if the * serialized content is XML 1.1). Using other character sequences than * the recommended ones can result in a document that is either not * serializable or not well-formed). * <br> On retrieval, the default value of this attribute is the * implementation specific default end-of-line sequence. DOM * implementations should choose the default to match the usual * convention for text files in the environment being used. * Implementations must choose a default sequence that matches one of * those allowed by XML 1.0 or XML 1.1, depending on the serialized * content. Setting this attribute to <code>null</code> will reset its * value to the default value. * <br> */ public void setNewLine(String newLine); /** * When the application provides a filter, the serializer will call out * to the filter before serializing each Node. The filter implementation * can choose to remove the node from the stream or to terminate the * serialization early. * <br> The filter is invoked after the operations requested by the * <code>DOMConfiguration</code> parameters have been applied. For * example, CDATA sections won't be passed to the filter if * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-cdata-sections'>cdata-sections</a>" * is set to <code>false</code>. */ public LSSerializerFilter getFilter(); /** * When the application provides a filter, the serializer will call out * to the filter before serializing each Node. The filter implementation * can choose to remove the node from the stream or to terminate the * serialization early. * <br> The filter is invoked after the operations requested by the * <code>DOMConfiguration</code> parameters have been applied. For * example, CDATA sections won't be passed to the filter if * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-cdata-sections'>cdata-sections</a>" * is set to <code>false</code>. */ public void setFilter(LSSerializerFilter filter); /** * Serialize the specified node as described above in the general * description of the <code>LSSerializer</code> interface. The output is * written to the supplied <code>LSOutput</code>. * <br> When writing to a <code>LSOutput</code>, the encoding is found by * looking at the encoding information that is reachable through the * <code>LSOutput</code> and the item to be written (or its owner * document) in this order: * <ol> * <li> <code>LSOutput.encoding</code>, * </li> * <li> * <code>Document.inputEncoding</code>, * </li> * <li> * <code>Document.xmlEncoding</code>. * </li> * </ol> * <br> If no encoding is reachable through the above properties, a * default encoding of "UTF-8" will be used. If the specified encoding * is not supported an "unsupported-encoding" fatal error is raised. * <br> If no output is specified in the <code>LSOutput</code>, a * "no-output-specified" fatal error is raised. * <br> The implementation is responsible of associating the appropriate * media type with the serialized data. * <br> When writing to a HTTP URI, a HTTP PUT is performed. When writing * to other types of URIs, the mechanism for writing the data to the URI * is implementation dependent. * @param nodeArg The node to serialize. * @param destination The destination for the serialized DOM. * @return Returns <code>true</code> if <code>node</code> was * successfully serialized. Return <code>false</code> in case the * normal processing stopped but the implementation kept serializing * the document; the result of the serialization being implementation * dependent then. * @exception LSException * SERIALIZE_ERR: Raised if the <code>LSSerializer</code> was unable to * serialize the node. DOM applications should attach a * <code>DOMErrorHandler</code> using the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-error-handler'>error-handler</a>" * if they wish to get details on the error. */ public boolean write(Node nodeArg, LSOutput destination) throws LSException; /** * A convenience method that acts as if <code>LSSerializer.write</code> * was called with a <code>LSOutput</code> with no encoding specified * and <code>LSOutput.systemId</code> set to the <code>uri</code> * argument. * @param nodeArg The node to serialize. * @param uri The URI to write to. * @return Returns <code>true</code> if <code>node</code> was * successfully serialized. Return <code>false</code> in case the * normal processing stopped but the implementation kept serializing * the document; the result of the serialization being implementation * dependent then. * @exception LSException * SERIALIZE_ERR: Raised if the <code>LSSerializer</code> was unable to * serialize the node. DOM applications should attach a * <code>DOMErrorHandler</code> using the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-error-handler'>error-handler</a>" * if they wish to get details on the error. */ public boolean writeToURI(Node nodeArg, String uri) throws LSException; /** * Serialize the specified node as described above in the general * description of the <code>LSSerializer</code> interface. The output is * written to a <code>DOMString</code> that is returned to the caller. * The encoding used is the encoding of the <code>DOMString</code> type, * i.e. UTF-16. Note that no Byte Order Mark is generated in a * <code>DOMString</code> object. * @param nodeArg The node to serialize. * @return Returns the serialized data. * @exception DOMException * DOMSTRING_SIZE_ERR: Raised if the resulting string is too long to * fit in a <code>DOMString</code>. * @exception LSException * SERIALIZE_ERR: Raised if the <code>LSSerializer</code> was unable to * serialize the node. DOM applications should attach a * <code>DOMErrorHandler</code> using the parameter * "<a href='https://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407/core.html#parameter-error-handler'>error-handler</a>" * if they wish to get details on the error. */ public String writeToString(Node nodeArg) throws DOMException, LSException; }