Module java.xml
Package javax.xml.stream.util

Class StreamReaderDelegate

  • All Implemented Interfaces:
    XMLStreamConstants, XMLStreamReader

    public class StreamReaderDelegate
extends Object
implements XMLStreamReader
    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.
    Since:
    1.6
    Version:
    1.0
    See Also:
    XMLStreamReader, EventReaderDelegate

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      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.
      XMLStreamReader getParent​()
      Get the parent of this instance.
      String getPIData​()
      Get the data section of a processing instruction
      String getPITarget​()
      Get the target of a processing instruction
      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.
      char[] getTextCharacters​()
      Returns an array which contains the characters from this event.
      int getTextCharacters​(int sourceStart, char[] target, int targetStart, int length)
      Gets the the text associated with a CHARACTERS, SPACE or CDATA 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 a boolean indicating whether the current event has a name (is a START_ELEMENT or END_ELEMENT).
      boolean hasNext​()
      Returns true if there are more parsing events and false if there are no more events.
      boolean hasText​()
      Return a boolean indicating whether the current event has text.
      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

    • Constructor Detail

      • StreamReaderDelegate

        public StreamReaderDelegate​()
        Construct an empty filter with no parent.

      • StreamReaderDelegate

        public StreamReaderDelegate​(XMLStreamReader reader)
        Construct an filter with the specified parent.
        Parameters:
        reader - the parent

    • Method Detail

      • setParent

        public void setParent​(XMLStreamReader reader)
        Set the parent of this instance.
        Parameters:
        reader - the new parent

      • getParent

        public XMLStreamReader getParent​()
        Get the parent of this instance.
        Returns:
        the parent or null if none is set

      • next

        public int next​()
         throws XMLStreamException
        Description copied from interface: XMLStreamReader
        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.

        Specified by:
        next in interface XMLStreamReader
        Returns:
        the integer code corresponding to the current parse event
        Throws:
        XMLStreamException - if there is an error processing the underlying XML source
        See Also:
        XMLEvent

      • nextTag

        public int nextTag​()
            throws XMLStreamException
        Description copied from interface: XMLStreamReader
        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;
        Specified by:
        nextTag in interface XMLStreamReader
        Returns:
        the event type of the element read (START_ELEMENT or END_ELEMENT)
        Throws:
        XMLStreamException - if the current event is not white space, PROCESSING_INSTRUCTION, START_ELEMENT or END_ELEMENT

      • getElementText

        public String getElementText​()
                      throws XMLStreamException
        Description copied from interface: XMLStreamReader
        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();
        Specified by:
        getElementText in interface XMLStreamReader
        Throws:
        XMLStreamException - if the current event is not a START_ELEMENT or if a non text element is encountered

      • require

        public void require​(int type,
                    String namespaceURI,
                    String localName)
             throws XMLStreamException
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        require in interface XMLStreamReader
        Parameters:
        type - the event type
        namespaceURI - the uri of the event, may be null
        localName - the localName of the event, may be null
        Throws:
        XMLStreamException - if the required values are not matched.

      • hasNext

        public boolean hasNext​()
                throws XMLStreamException
        Description copied from interface: XMLStreamReader
        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
        Specified by:
        hasNext in interface XMLStreamReader
        Returns:
        true if there are more events, false otherwise
        Throws:
        XMLStreamException - if there is a fatal error detecting the next state

      • getNamespaceURI

        public String getNamespaceURI​(String prefix)
        Description copied from interface: XMLStreamReader
        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/

        Specified by:
        getNamespaceURI in interface XMLStreamReader
        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

      • getNamespaceContext

        public NamespaceContext getNamespaceContext​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getNamespaceContext in interface XMLStreamReader
        Returns:
        return a namespace context

      • isStartElement

        public boolean isStartElement​()
        Description copied from interface: XMLStreamReader
        Returns true if the cursor points to a start tag (otherwise false)
        Specified by:
        isStartElement in interface XMLStreamReader
        Returns:
        true if the cursor points to a start tag, false otherwise

      • isEndElement

        public boolean isEndElement​()
        Description copied from interface: XMLStreamReader
        Returns true if the cursor points to an end tag (otherwise false)
        Specified by:
        isEndElement in interface XMLStreamReader
        Returns:
        true if the cursor points to an end tag, false otherwise

      • isCharacters

        public boolean isCharacters​()
        Description copied from interface: XMLStreamReader
        Returns true if the cursor points to a character data event
        Specified by:
        isCharacters in interface XMLStreamReader
        Returns:
        true if the cursor points to character data, false otherwise

      • isWhiteSpace

        public boolean isWhiteSpace​()
        Description copied from interface: XMLStreamReader
        Returns true if the cursor points to a character data event that consists of all whitespace
        Specified by:
        isWhiteSpace in interface XMLStreamReader
        Returns:
        true if the cursor points to all whitespace, false otherwise

      • getAttributeValue

        public String getAttributeValue​(String namespaceUri,
                                String localName)
        Description copied from interface: XMLStreamReader
        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
        Specified by:
        getAttributeValue in interface XMLStreamReader
        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

      • getAttributeCount

        public int getAttributeCount​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getAttributeCount in interface XMLStreamReader
        Returns:
        returns the number of attributes

      • getAttributeName

        public QName getAttributeName​(int index)
        Description copied from interface: XMLStreamReader
        Returns the qname of the attribute at the provided index
        Specified by:
        getAttributeName in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        the QName of the attribute

      • getAttributePrefix

        public String getAttributePrefix​(int index)
        Description copied from interface: XMLStreamReader
        Returns the prefix of this attribute at the provided index
        Specified by:
        getAttributePrefix in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        the prefix of the attribute

      • getAttributeNamespace

        public String getAttributeNamespace​(int index)
        Description copied from interface: XMLStreamReader
        Returns the namespace of the attribute at the provided index
        Specified by:
        getAttributeNamespace in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        the namespace URI (can be null)

      • getAttributeLocalName

        public String getAttributeLocalName​(int index)
        Description copied from interface: XMLStreamReader
        Returns the localName of the attribute at the provided index
        Specified by:
        getAttributeLocalName in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        the localName of the attribute

      • getAttributeType

        public String getAttributeType​(int index)
        Description copied from interface: XMLStreamReader
        Returns the XML type of the attribute at the provided index
        Specified by:
        getAttributeType in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        the XML type of the attribute

      • getAttributeValue

        public String getAttributeValue​(int index)
        Description copied from interface: XMLStreamReader
        Returns the value of the attribute at the index
        Specified by:
        getAttributeValue in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        the attribute value

      • isAttributeSpecified

        public boolean isAttributeSpecified​(int index)
        Description copied from interface: XMLStreamReader
        Returns a boolean which indicates if this attribute was created by default
        Specified by:
        isAttributeSpecified in interface XMLStreamReader
        Parameters:
        index - the position of the attribute
        Returns:
        true if this is a default attribute

      • getNamespaceCount

        public int getNamespaceCount​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getNamespaceCount in interface XMLStreamReader
        Returns:
        returns the number of namespace declarations on this specific element

      • getNamespacePrefix

        public String getNamespacePrefix​(int index)
        Description copied from interface: XMLStreamReader
        Returns the prefix for the namespace declared at the index. Returns null if this is the default namespace declaration
        Specified by:
        getNamespacePrefix in interface XMLStreamReader
        Parameters:
        index - the position of the namespace declaration
        Returns:
        returns the namespace prefix

      • getNamespaceURI

        public String getNamespaceURI​(int index)
        Description copied from interface: XMLStreamReader
        Returns the uri for the namespace declared at the index.
        Specified by:
        getNamespaceURI in interface XMLStreamReader
        Parameters:
        index - the position of the namespace declaration
        Returns:
        returns the namespace uri

      • getText

        public String getText​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getText in interface XMLStreamReader
        Returns:
        the current text or null

      • getTextCharacters

        public int getTextCharacters​(int sourceStart,
                             char[] target,
                             int targetStart,
                             int length)
                      throws XMLStreamException
        Description copied from interface: XMLStreamReader
        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".
        Specified by:
        getTextCharacters in interface XMLStreamReader
        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
        Throws:
        XMLStreamException - if the underlying XML source is not well-formed

      • getTextCharacters

        public char[] getTextCharacters​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getTextCharacters in interface XMLStreamReader
        Returns:
        the current text or an empty array

      • getTextStart

        public int getTextStart​()
        Description copied from interface: XMLStreamReader
        Returns the offset into the text character array where the first character (of this text event) is stored.
        Specified by:
        getTextStart in interface XMLStreamReader
        Returns:
        the starting position of the text in the character array

      • getTextLength

        public int getTextLength​()
        Description copied from interface: XMLStreamReader
        Returns the length of the sequence of characters for this Text event within the text character array.
        Specified by:
        getTextLength in interface XMLStreamReader
        Returns:
        the length of the text

      • getEncoding

        public String getEncoding​()
        Description copied from interface: XMLStreamReader
        Return input encoding if known or null if unknown.
        Specified by:
        getEncoding in interface XMLStreamReader
        Returns:
        the encoding of this instance or null

      • hasText

        public boolean hasText​()
        Description copied from interface: XMLStreamReader
        Return a boolean indicating whether the current event has text. The following events have text: CHARACTERS,DTD ,ENTITY_REFERENCE, COMMENT, SPACE
        Specified by:
        hasText in interface XMLStreamReader
        Returns:
        true if the event has text, false otherwise

      • getLocation

        public Location getLocation​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getLocation in interface XMLStreamReader
        Returns:
        the location of the cursor

      • getName

        public QName getName​()
        Description copied from interface: XMLStreamReader
        Returns a QName for the current START_ELEMENT or END_ELEMENT event
        Specified by:
        getName in interface XMLStreamReader
        Returns:
        the QName for the current START_ELEMENT or END_ELEMENT event

      • getLocalName

        public String getLocalName​()
        Description copied from interface: XMLStreamReader
        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
        Specified by:
        getLocalName in interface XMLStreamReader
        Returns:
        the localName

      • hasName

        public boolean hasName​()
        Description copied from interface: XMLStreamReader
        returns a boolean indicating whether the current event has a name (is a START_ELEMENT or END_ELEMENT).
        Specified by:
        hasName in interface XMLStreamReader
        Returns:
        true if the event has a name, false otherwise

      • getNamespaceURI

        public String getNamespaceURI​()
        Description copied from interface: XMLStreamReader
        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.
        Specified by:
        getNamespaceURI in interface XMLStreamReader
        Returns:
        the URI bound to this elements prefix, the default namespace, or null

      • getPrefix

        public String getPrefix​()
        Description copied from interface: XMLStreamReader
        Returns the prefix of the current event or null if the event does not have a prefix
        Specified by:
        getPrefix in interface XMLStreamReader
        Returns:
        the prefix or null

      • getVersion

        public String getVersion​()
        Description copied from interface: XMLStreamReader
        Get the xml version declared on the xml declaration Returns null if none was declared
        Specified by:
        getVersion in interface XMLStreamReader
        Returns:
        the XML version or null

      • isStandalone

        public boolean isStandalone​()
        Description copied from interface: XMLStreamReader
        Get the standalone declaration from the xml declaration
        Specified by:
        isStandalone in interface XMLStreamReader
        Returns:
        true if this is standalone, or false otherwise

      • standaloneSet

        public boolean standaloneSet​()
        Description copied from interface: XMLStreamReader
        Checks if standalone was set in the document
        Specified by:
        standaloneSet in interface XMLStreamReader
        Returns:
        true if standalone was set in the document, or false otherwise

      • getCharacterEncodingScheme

        public String getCharacterEncodingScheme​()
        Description copied from interface: XMLStreamReader
        Returns the character encoding declared on the xml declaration Returns null if none was declared
        Specified by:
        getCharacterEncodingScheme in interface XMLStreamReader
        Returns:
        the encoding declared in the document or null

      • getProperty

        public Object getProperty​(String name)
        Description copied from interface: XMLStreamReader
        Get the value of a feature/property from the underlying implementation
        Specified by:
        getProperty in interface XMLStreamReader
        Parameters:
        name - The name of the property, may not be null
        Returns:
        The value of the property