org.w3c.dom.ls.LSSerializer Maven / Gradle / Ivy
/*
* 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.DOMException;
import org.w3c.dom.Node;
/**
* A LSSerializer 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 Document object and its
* children are never altered by the serialization operation.
* During serialization of XML data, namespace fixup is done as defined in [DOM Level 3 Core]
* , Appendix B. [DOM Level 2 Core]
* allows empty strings as a real namespace URI. If the
* namespaceURI of a Node is empty string, the
* serialization will treat them as null, ignoring the prefix
* if any.
*
LSSerializer accepts any node type for serialization. For
* nodes of type Document or Entity, 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.
*
Within a Document, DocumentFragment, or
* Entity being serialized, Nodes are processed as
* follows
*
* -
Document nodes are written, including the XML
* declaration (unless the parameter "xml-declaration" is set to
* false) and a DTD subset, if one exists in the DOM. Writing a
* Document node serializes the entire document.
*
* -
*
Entity nodes, when written directly by
* LSSerializer.write, outputs the entity expansion but no
* namespace fixup is done. The resulting output will be valid as an
* external entity.
*
* - If the parameter "
* entities" is set to
true, EntityReference nodes are
* serialized as an entity reference of the form "
* &entityName;" in the output. Child nodes (the expansion)
* of the entity reference are ignored. If the parameter "
* entities" is set to false, only the children of the entity reference
* are serialized. EntityReference nodes with no children (no
* corresponding Entity node or the corresponding
* Entity nodes have no children) are always serialized.
*
* -
*
CDATAsections containing content characters that cannot be
* represented in the specified output encoding are handled according to the
* "
* split-cdata-sections" parameter. If the parameter is set to true,
* CDATAsections 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 false, unrepresentable characters in a
* CDATAsection are reported as
* "wf-invalid-character" errors if the parameter "
* well-formed" is set to true. The error is not recoverable - there is no
* mechanism for supplying alternative characters and continuing with the
* serialization.
*
* -
DocumentFragment nodes are serialized by
* serializing the children of the document fragment in the order they
* appear in the document fragment.
*
* - All other node types (Element, Text,
* etc.) are serialized to their corresponding XML source form.
*
*
* Note: The serialization of a Node does not always
* generate a well-formed XML document, i.e. a LSParser might
* throw fatal errors when parsing the resulting serialization.
*
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 < and &. The other predefined
* entities (>, ', and ") might not be used, except
* where needed (e.g. using > 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).
*
To allow attribute values to contain both single and double quotes, the
* apostrophe or single-quote character (') may be represented as
* "'", and the double-quote character (") as """. 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.
*
Within markup, but outside of attributes, any occurrence of a character
* that cannot be represented in the output character encoding is reported
* as a DOMError fatal error. An example would be serializing
* the element <LaCa\u00f1ada/> with encoding="us-ascii".
* This will result with a generation of a DOMError
* "wf-invalid-character-in-node-name" (as proposed in "
* well-formed").
*
When requested by setting the parameter "
* normalize-characters" on LSSerializer to true, character normalization is
* performed according to the definition of fully
* normalized characters included in appendix E of [XML 1.1] 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.
*
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
* LSOutput.byteStream or LSOutput.systemId. 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. encoding="UTF-16" will appear if UTF-16 was
* requested).
*
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 [DOM Level 3 Core]
* .
*
While serializing a document, the parameter "discard-default-content"
* controls whether or not non-specified data is serialized.
*
While serializing, errors and warnings are reported to the application
* through the error handler (LSSerializer.domConfig's "
* error-handler" 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 (
* DOMError.type) of errors and warnings defined by this
* specification are:
*
* "no-output-specified" [fatal]- Raised when
* writing to a
LSOutput if no output is specified in the
* LSOutput.
* -
*
"unbound-prefix-in-entity-reference" [fatal]
* - Raised if the
* configuration parameter "
* namespaces" is set to
true and an entity whose replacement text
* contains unbound namespace prefixes is referenced in a location where
* there are no bindings for the namespace prefixes.
* -
*
"unsupported-encoding" [fatal]
* - Raised if an unsupported
* encoding is encountered.
*
* 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.
*
See also the Document Object Model (DOM) Level 3 Load
and Save Specification.
*/
public interface LSSerializer {
/**
* The DOMConfiguration object used by the
* LSSerializer when serializing a DOM node.
*
In addition to the parameters recognized by the
* DOMConfiguration interface defined in [DOM Level 3 Core]
* , the DOMConfiguration objects for
* LSSerializer adds, or modifies, the following
* parameters:
*
* "canonical-form"-
*
* true- [optional] Writes the document according to the rules specified in [Canonical XML].
* In addition to the behavior described in "
* canonical-form" [DOM Level 3 Core]
* , setting this parameter to
true will set the parameters
* "format-pretty-print", "discard-default-content", and "xml-declaration
* ", to false. Setting one of those parameters to
* true will set this parameter to false.
* Serializing an XML 1.1 document when "canonical-form" is
* true will generate a fatal error.
* false- [required] (default) Do not canonicalize the output.
*
* "discard-default-content"-
*
* -
*
true
* - [required] (default) Use the
Attr.specified 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 Attr.specified attribute, and so on) to
* determine what attributes and content to discard if this parameter is
* set to true.
* false- [required]Keep all attributes and all content.
*
* "format-pretty-print"-
*
* -
*
true
* - [optional] 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.
* -
*
false
* - [required] (default) Don't pretty-print the result.
*
* -
*
"ignore-unknown-character-denormalizations"
* -
*
* -
*
true
* - [required] (default) If, while verifying full normalization when [XML 1.1] is
* supported, a character is encountered for which the normalization
* properties cannot be determined, then raise a
*
"unknown-character-denormalization" warning (instead of
* raising an error, if this parameter is not set) and ignore any
* possible denormalizations caused by these characters.
* -
*
false
* - [optional] Report a fatal error if a character is encountered for which the
* processor cannot determine the normalization properties.
*
* -
*
"normalize-characters"
* - This parameter is equivalent to
* the one defined by
DOMConfiguration in [DOM Level 3 Core]
* . Unlike in the Core, the default value for this parameter is
* true. While DOM implementations are not required to
* support fully
* normalizing the characters in the document according to appendix E of [XML 1.1], this
* parameter must be activated by default if supported.
* -
*
"xml-declaration"
* -
*
* true- [required] (default) If a
Document, Element, or Entity
* node is serialized, the XML declaration, or text declaration, should
* be included. The version (Document.xmlVersion 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
* LSSerializer.write for details on how to find the output
* encoding) are specified in the serialized XML declaration.
* -
*
false
* - [required] Do not serialize the XML and text declarations. Report a
*
"xml-declaration-needed" warning if this will cause
* problems (i.e. the serialized data is of an XML version other than [XML 1.0], or an
* encoding would be needed to be able to re-parse the serialized data).
*
*
*/
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 [XML 1.0], if the
* serialized content is XML 1.0 or section 2.11, "End-of-Line Handling"
* in [XML 1.1], 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).
*
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 null will reset its
* value to the default value.
*
*/
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 [XML 1.0], if the
* serialized content is XML 1.0 or section 2.11, "End-of-Line Handling"
* in [XML 1.1], 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).
*
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 null will reset its
* value to the default value.
*
*/
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.
*
The filter is invoked after the operations requested by the
* DOMConfiguration parameters have been applied. For
* example, CDATA sections won't be passed to the filter if "
* cdata-sections" is set to false.
*
* @hide
*/
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.
*
The filter is invoked after the operations requested by the
* DOMConfiguration parameters have been applied. For
* example, CDATA sections won't be passed to the filter if "
* cdata-sections" is set to false.
*
* @hide
*/
public void setFilter(LSSerializerFilter filter);
/**
* Serialize the specified node as described above in the general
* description of the LSSerializer interface. The output is
* written to the supplied LSOutput.
*
When writing to a LSOutput, the encoding is found by
* looking at the encoding information that is reachable through the
* LSOutput and the item to be written (or its owner
* document) in this order:
*
* -
LSOutput.encoding,
*
* -
*
Document.inputEncoding,
*
* -
*
Document.xmlEncoding.
*
*
*
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.
*
If no output is specified in the LSOutput, a
* "no-output-specified" fatal error is raised.
*
The implementation is responsible of associating the appropriate
* media type with the serialized data.
*
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 true if node was
* successfully serialized. Return false 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 LSSerializer was unable to
* serialize the node. DOM applications should attach a
* DOMErrorHandler using the parameter "
* error-handler" 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 LSSerializer.write
* was called with a LSOutput with no encoding specified
* and LSOutput.systemId set to the uri
* argument.
* @param nodeArg The node to serialize.
* @param uri The URI to write to.
* @return Returns true if node was
* successfully serialized. Return false 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 LSSerializer was unable to
* serialize the node. DOM applications should attach a
* DOMErrorHandler using the parameter "
* error-handler" 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 LSSerializer interface. The output is
* written to a DOMString that is returned to the caller.
* The encoding used is the encoding of the DOMString type,
* i.e. UTF-16. Note that no Byte Order Mark is generated in a
* DOMString 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 DOMString.
* @exception LSException
* SERIALIZE_ERR: Raised if the LSSerializer was unable to
* serialize the node. DOM applications should attach a
* DOMErrorHandler using the parameter "
* error-handler" if they wish to get details on the error.
*/
public String writeToString(Node nodeArg)
throws DOMException, LSException;
}