public class

StreamReaderDelegate

extends Object
implements XMLStreamReader
java.lang.Object
   ↳ javax.xml.stream.util.StreamReaderDelegate

Class Overview

This is the base class for deriving an XMLStreamReader filter This class is designed to sit between an XMLStreamReader and an application's XMLStreamReader. By default each method does nothing but call the corresponding method on the parent interface.

Summary

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Inherited Constants
From interface javax.xml.stream.XMLStreamConstants
Public Constructors
StreamReaderDelegate()
Construct an empty filter with no parent.
StreamReaderDelegate(XMLStreamReader reader)
Construct an filter with the specified parent.
Public Methods
void close()
Frees any resources associated with this Reader.
int getAttributeCount()
Returns the count of attributes on this START_ELEMENT, this method is only valid on a START_ELEMENT or ATTRIBUTE.
String getAttributeLocalName(int index)
Returns the localName of the attribute at the provided index
QName getAttributeName(int index)
Returns the qname of the attribute at the provided index
String getAttributeNamespace(int index)
Returns the namespace of the attribute at the provided index
String getAttributePrefix(int index)
Returns the prefix of this attribute at the provided index
String getAttributeType(int index)
Returns the XML type of the attribute at the provided index
String getAttributeValue(int index)
Returns the value of the attribute at the index
String getAttributeValue(String namespaceUri, String localName)
Returns the normalized attribute value of the attribute with the namespace and localName If the namespaceURI is null the namespace is not checked for equality
String getCharacterEncodingScheme()
Returns the character encoding declared on the xml declaration Returns null if none was declared
String getElementText()
Reads the content of a text-only element, an exception is thrown if this is not a text-only element.
String getEncoding()
Return input encoding if known or null if unknown.
int getEventType()
Returns an integer code that indicates the type of the event the cursor is pointing to.
String getLocalName()
Returns the (local) name of the current event.
Location getLocation()
Return the current location of the processor.
QName getName()
Returns a QName for the current START_ELEMENT or END_ELEMENT event
NamespaceContext getNamespaceContext()
Returns a read only namespace context for the current position.
int getNamespaceCount()
Returns the count of namespaces declared on this START_ELEMENT or END_ELEMENT, this method is only valid on a START_ELEMENT, END_ELEMENT or NAMESPACE.
String getNamespacePrefix(int index)
Returns the prefix for the namespace declared at the index.
String getNamespaceURI()
If the current event is a START_ELEMENT or END_ELEMENT this method returns the URI of the prefix or the default namespace.
String getNamespaceURI(int index)
Returns the uri for the namespace declared at the index.
String getNamespaceURI(String prefix)
Return the uri for the given prefix.
String getPIData()
Get the data section of a processing instruction
String getPITarget()
Get the target of a processing instruction
XMLStreamReader getParent()
Get the parent of this instance.
String getPrefix()
Returns the prefix of the current event or null if the event does not have a prefix
Object getProperty(String name)
Get the value of a feature/property from the underlying implementation
String getText()
Returns the current value of the parse event as a string, this returns the string value of a CHARACTERS event, returns the value of a COMMENT, the replacement value for an ENTITY_REFERENCE, the string value of a CDATA section, the string value for a SPACE event, or the String value of the internal subset of the DTD.
int getTextCharacters(int sourceStart, char[] target, int targetStart, int length)
Gets the the text associated with a CHARACTERS, SPACE or CDATA event.
char[] getTextCharacters()
Returns an array which contains the characters from this event.
int getTextLength()
Returns the length of the sequence of characters for this Text event within the text character array.
int getTextStart()
Returns the offset into the text character array where the first character (of this text event) is stored.
String getVersion()
Get the xml version declared on the xml declaration Returns null if none was declared
boolean hasName()
returns true if the current event has a name (is a START_ELEMENT or END_ELEMENT) returns false otherwise
boolean hasNext()
Returns true if there are more parsing events and false if there are no more events.
boolean hasText()
Return true if the current event has text, false otherwise The following events have text: CHARACTERS,DTD ,ENTITY_REFERENCE, COMMENT, SPACE
boolean isAttributeSpecified(int index)
Returns a boolean which indicates if this attribute was created by default
boolean isCharacters()
Returns true if the cursor points to a character data event
boolean isEndElement()
Returns true if the cursor points to an end tag (otherwise false)
boolean isStandalone()
Get the standalone declaration from the xml declaration
boolean isStartElement()
Returns true if the cursor points to a start tag (otherwise false)
boolean isWhiteSpace()
Returns true if the cursor points to a character data event that consists of all whitespace
int next()
Get next parsing event - a processor may return all contiguous character data in a single chunk, or it may split it into several chunks.
int nextTag()
Skips any white space (isWhiteSpace() returns true), COMMENT, or PROCESSING_INSTRUCTION, until a START_ELEMENT or END_ELEMENT is reached.
void require(int type, String namespaceURI, String localName)
Test if the current event is of the given type and if the namespace and name match the current namespace and name of the current event.
void setParent(XMLStreamReader reader)
Set the parent of this instance.
boolean standaloneSet()
Checks if standalone was set in the document
[Expand]
Inherited Methods
From class java.lang.Object
From interface javax.xml.stream.XMLStreamReader

Public Constructors

public StreamReaderDelegate ()

Construct an empty filter with no parent.

public StreamReaderDelegate (XMLStreamReader reader)

Construct an filter with the specified parent.

Parameters
reader the parent

Public Methods

public void close ()

Frees any resources associated with this Reader. This method does not close the underlying input source.

public int getAttributeCount ()

Returns the count of attributes on this START_ELEMENT, this method is only valid on a START_ELEMENT or ATTRIBUTE. This count excludes namespace definitions. Attribute indices are zero-based.

Returns
  • returns the number of attributes

public String getAttributeLocalName (int index)

Returns the localName of the attribute at the provided index

Parameters
index the position of the attribute
Returns
  • the localName of the attribute

public QName getAttributeName (int index)

Returns the qname of the attribute at the provided index

Parameters
index the position of the attribute
Returns
  • the QName of the attribute

public String getAttributeNamespace (int index)

Returns the namespace of the attribute at the provided index

Parameters
index the position of the attribute
Returns
  • the namespace URI (can be null)

public String getAttributePrefix (int index)

Returns the prefix of this attribute at the provided index

Parameters
index the position of the attribute
Returns
  • the prefix of the attribute

public String getAttributeType (int index)

Returns the XML type of the attribute at the provided index

Parameters
index the position of the attribute
Returns
  • the XML type of the attribute

public String getAttributeValue (int index)

Returns the value of the attribute at the index

Parameters
index the position of the attribute
Returns
  • the attribute value

public String getAttributeValue (String namespaceUri, String localName)

Returns the normalized attribute value of the attribute with the namespace and localName If the namespaceURI is null the namespace is not checked for equality

Parameters
namespaceUri the namespace of the attribute
localName the local name of the attribute, cannot be null
Returns
  • returns the value of the attribute , returns null if not found

public String getCharacterEncodingScheme ()

Returns the character encoding declared on the xml declaration Returns null if none was declared

Returns
  • the encoding declared in the document or null

public String getElementText ()

Reads the content of a text-only element, an exception is thrown if this is not a text-only element. Regardless of value of javax.xml.stream.isCoalescing this method always returns coalesced content.
Precondition: the current event is START_ELEMENT.
Postcondition: the current event is the corresponding END_ELEMENT.
The method does the following (implementations are free to optimized but must do equivalent processing):

 if(getEventType() != XMLStreamConstants.START_ELEMENT) {
 throw new XMLStreamException(
 "parser must be on START_ELEMENT to read next text", getLocation());
 }
 int eventType = next();
 StringBuffer content = new StringBuffer();
 while(eventType != XMLStreamConstants.END_ELEMENT ) {
 if(eventType == XMLStreamConstants.CHARACTERS
 || eventType == XMLStreamConstants.CDATA
 || eventType == XMLStreamConstants.SPACE
 || eventType == XMLStreamConstants.ENTITY_REFERENCE) {
 buf.append(getText());
 } else if(eventType == XMLStreamConstants.PROCESSING_INSTRUCTION
 || eventType == XMLStreamConstants.COMMENT) {
 // skipping
 } else if(eventType == XMLStreamConstants.END_DOCUMENT) {
 throw new XMLStreamException(
 "unexpected end of document when reading element text content", this);
 } else if(eventType == XMLStreamConstants.START_ELEMENT) {
 throw new XMLStreamException(
 "element text content may not contain START_ELEMENT", getLocation());
 } else {
 throw new XMLStreamException(
 "Unexpected event type "+eventType, getLocation());
 }
 eventType = next();
 }
 return buf.toString();
 

public String getEncoding ()

Return input encoding if known or null if unknown.

Returns
  • the encoding of this instance or null

public int getEventType ()

Returns an integer code that indicates the type of the event the cursor is pointing to.

public String getLocalName ()

Returns the (local) name of the current event. For START_ELEMENT or END_ELEMENT returns the (local) name of the current element. For ENTITY_REFERENCE it returns entity name. The current event must be START_ELEMENT or END_ELEMENT, or ENTITY_REFERENCE

Returns
  • the localName

public Location getLocation ()

Return the current location of the processor. If the Location is unknown the processor should return an implementation of Location that returns -1 for the location and null for the publicId and systemId. The location information is only valid until next() is called.

public QName getName ()

Returns a QName for the current START_ELEMENT or END_ELEMENT event

Returns
  • the QName for the current START_ELEMENT or END_ELEMENT event

public NamespaceContext getNamespaceContext ()

Returns a read only namespace context for the current position. The context is transient and only valid until a call to next() changes the state of the reader.

Returns
  • return a namespace context

public int getNamespaceCount ()

Returns the count of namespaces declared on this START_ELEMENT or END_ELEMENT, this method is only valid on a START_ELEMENT, END_ELEMENT or NAMESPACE. On an END_ELEMENT the count is of the namespaces that are about to go out of scope. This is the equivalent of the information reported by SAX callback for an end element event.

Returns
  • returns the number of namespace declarations on this specific element

public String getNamespacePrefix (int index)

Returns the prefix for the namespace declared at the index. Returns null if this is the default namespace declaration

Parameters
index the position of the namespace declaration
Returns
  • returns the namespace prefix

public String getNamespaceURI ()

If the current event is a START_ELEMENT or END_ELEMENT this method returns the URI of the prefix or the default namespace. Returns null if the event does not have a prefix.

Returns
  • the URI bound to this elements prefix, the default namespace, or null

public String getNamespaceURI (int index)

Returns the uri for the namespace declared at the index.

Parameters
index the position of the namespace declaration
Returns
  • returns the namespace uri

public String getNamespaceURI (String prefix)

Return the uri for the given prefix. The uri returned depends on the current state of the processor.

NOTE:The 'xml' prefix is bound as defined in Namespaces in XML specification to "http://www.w3.org/XML/1998/namespace".

NOTE: The 'xmlns' prefix must be resolved to following namespace http://www.w3.org/2000/xmlns/

Parameters
prefix The prefix to lookup, may not be null
Returns
  • the uri bound to the given prefix or null if it is not bound

public String getPIData ()

Get the data section of a processing instruction

Returns
  • the data or null

public String getPITarget ()

Get the target of a processing instruction

Returns
  • the target or null

public XMLStreamReader getParent ()

Get the parent of this instance.

Returns
  • the parent or null if none is set

public String getPrefix ()

Returns the prefix of the current event or null if the event does not have a prefix

Returns
  • the prefix or null

public Object getProperty (String name)

Get the value of a feature/property from the underlying implementation

Parameters
name The name of the property, may not be null
Returns
  • The value of the property

public String getText ()

Returns the current value of the parse event as a string, this returns the string value of a CHARACTERS event, returns the value of a COMMENT, the replacement value for an ENTITY_REFERENCE, the string value of a CDATA section, the string value for a SPACE event, or the String value of the internal subset of the DTD. If an ENTITY_REFERENCE has been resolved, any character data will be reported as CHARACTERS events.

Returns
  • the current text or null

public int getTextCharacters (int sourceStart, char[] target, int targetStart, int length)

Gets the the text associated with a CHARACTERS, SPACE or CDATA event. Text starting a "sourceStart" is copied into "target" starting at "targetStart". Up to "length" characters are copied. The number of characters actually copied is returned. The "sourceStart" argument must be greater or equal to 0 and less than or equal to the number of characters associated with the event. Usually, one requests text starting at a "sourceStart" of 0. If the number of characters actually copied is less than the "length", then there is no more text. Otherwise, subsequent calls need to be made until all text has been retrieved. For example: int length = 1024; char[] myBuffer = new char[ length ]; for ( int sourceStart = 0 ; ; sourceStart += length ) { int nCopied = stream.getTextCharacters( sourceStart, myBuffer, 0, length ); if (nCopied < length) break; } XMLStreamException may be thrown if there are any XML errors in the underlying source. The "targetStart" argument must be greater than or equal to 0 and less than the length of "target", Length must be greater than 0 and "targetStart + length" must be less than or equal to length of "target".

Parameters
sourceStart the index of the first character in the source array to copy
target the destination array
targetStart the start offset in the target array
length the number of characters to copy
Returns
  • the number of characters actually copied

public char[] getTextCharacters ()

Returns an array which contains the characters from this event. This array should be treated as read-only and transient. I.e. the array will contain the text characters until the XMLStreamReader moves on to the next event. Attempts to hold onto the character array beyond that time or modify the contents of the array are breaches of the contract for this interface.

Returns
  • the current text or an empty array

public int getTextLength ()

Returns the length of the sequence of characters for this Text event within the text character array.

public int getTextStart ()

Returns the offset into the text character array where the first character (of this text event) is stored.

public String getVersion ()

Get the xml version declared on the xml declaration Returns null if none was declared

Returns
  • the XML version or null

public boolean hasName ()

returns true if the current event has a name (is a START_ELEMENT or END_ELEMENT) returns false otherwise

public boolean hasNext ()

Returns true if there are more parsing events and false if there are no more events. This method will return false if the current state of the XMLStreamReader is END_DOCUMENT

Returns
  • true if there are more events, false otherwise

public boolean hasText ()

Return true if the current event has text, false otherwise The following events have text: CHARACTERS,DTD ,ENTITY_REFERENCE, COMMENT, SPACE

public boolean isAttributeSpecified (int index)

Returns a boolean which indicates if this attribute was created by default

Parameters
index the position of the attribute
Returns
  • true if this is a default attribute

public boolean isCharacters ()

Returns true if the cursor points to a character data event

Returns
  • true if the cursor points to character data, false otherwise

public boolean isEndElement ()

Returns true if the cursor points to an end tag (otherwise false)

Returns
  • true if the cursor points to an end tag, false otherwise

public boolean isStandalone ()

Get the standalone declaration from the xml declaration

Returns
  • true if this is standalone, or false otherwise

public boolean isStartElement ()

Returns true if the cursor points to a start tag (otherwise false)

Returns
  • true if the cursor points to a start tag, false otherwise

public boolean isWhiteSpace ()

Returns true if the cursor points to a character data event that consists of all whitespace

Returns
  • true if the cursor points to all whitespace, false otherwise

public int next ()

Get next parsing event - a processor may return all contiguous character data in a single chunk, or it may split it into several chunks. If the property javax.xml.stream.isCoalescing is set to true element content must be coalesced and only one CHARACTERS event must be returned for contiguous element content or CDATA Sections. By default entity references must be expanded and reported transparently to the application. An exception will be thrown if an entity reference cannot be expanded. If element content is empty (i.e. content is "") then no CHARACTERS event will be reported.

Given the following XML:
<foo><!--description-->content text<![CDATA[<greeting>Hello</greeting>]]>other content</foo>
The behavior of calling next() when being on foo will be:
1- the comment (COMMENT)
2- then the characters section (CHARACTERS)
3- then the CDATA section (another CHARACTERS)
4- then the next characters section (another CHARACTERS)
5- then the END_ELEMENT

NOTE: empty element (such as <tag/>) will be reported with two separate events: START_ELEMENT, END_ELEMENT - This preserves parsing equivalency of empty element to <tag></tag>. This method will throw an IllegalStateException if it is called after hasNext() returns false.

Returns
  • the integer code corresponding to the current parse event

public int nextTag ()

Skips any white space (isWhiteSpace() returns true), COMMENT, or PROCESSING_INSTRUCTION, until a START_ELEMENT or END_ELEMENT is reached. If other than white space characters, COMMENT, PROCESSING_INSTRUCTION, START_ELEMENT, END_ELEMENT are encountered, an exception is thrown. This method should be used when processing element-only content seperated by white space.
Precondition: none
Postcondition: the current event is START_ELEMENT or END_ELEMENT and cursor may have moved over any whitespace event.
Essentially it does the following (implementations are free to optimized but must do equivalent processing):

 int eventType = next();
 while((eventType == XMLStreamConstants.CHARACTERS && isWhiteSpace()) // skip whitespace
 || (eventType == XMLStreamConstants.CDATA && isWhiteSpace())
 // skip whitespace
 || eventType == XMLStreamConstants.SPACE
 || eventType == XMLStreamConstants.PROCESSING_INSTRUCTION
 || eventType == XMLStreamConstants.COMMENT
 ) {
 eventType = next();
 }
 if (eventType != XMLStreamConstants.START_ELEMENT && eventType != XMLStreamConstants.END_ELEMENT) {
 throw new String XMLStreamException("expected start or end tag", getLocation());
 }
 return eventType;
 

Returns
  • the event type of the element read (START_ELEMENT or END_ELEMENT)

public void require (int type, String namespaceURI, String localName)

Test if the current event is of the given type and if the namespace and name match the current namespace and name of the current event. If the namespaceURI is null it is not checked for equality, if the localName is null it is not checked for equality.

Parameters
type the event type
namespaceURI the uri of the event, may be null
localName the localName of the event, may be null

public void setParent (XMLStreamReader reader)

Set the parent of this instance.

Parameters
reader the new parent

public boolean standaloneSet ()

Checks if standalone was set in the document

Returns
  • true if standalone was set in the document, or false otherwise