Package com.sun.xml.rpc.streaming

Interface XMLReader

All Known Implementing Classes:
FastInfosetReader, LoggingXMLReader, RecordedXMLReader, StAXReader, XMLReaderBase, XMLReaderImpl, XmlTreeReader
public interface XMLReader

XMLReader provides a high-level streaming parser interface for reading XML documents.

The next() method is used to read events from the XML document.

Each time it is called, next() returns the new state of the reader.

Possible states are: BOF, the initial state, START, denoting the start tag of an element, END, denoting the end tag of an element, CHARS, denoting the character content of an element, PI, denoting a processing instruction, EOF, denoting the end of the document.

Depending on the state the reader is in, one or more of the following query methods will be meaningful: getName(), getURI(), getLocalName(), getAttributes(), getValue().

Elements visited by a XMLReader are tagged with unique IDs. The ID of the current element can be found by calling getElementId().

A XMLReader is always namespace-aware, and keeps track of the namespace declarations which are in scope at any time during streaming. The getURI(java.lang.String) method can be used to find the URI associated to a given prefix in the current scope.

XMLReaders can be created using a XMLReaderFactory.

Some utility methods, nextContent() and nextElementContent() make it possible to ignore whitespace and processing instructions with minimum impact on the client code.

Similarly, the skipElement() and skipElement(int elementId) methods allow to skip to the end tag of an element ignoring all its content.

Finally, the recordElement() method can be invoked when the XMLReader is positioned on the start tag of an element to record the element's contents so that they can be played back later.

Author:
JAX-RPC Development Team
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    BOF
    The initial state of a XMLReader.
    static final int
    CHARS
    The state denoting the character content of an element.
    static final int
    END
    The state denoting the end tag of an element.
    static final int
    EOF
    The state denoting that the end of the document has been reached.
    static final int
    PI
    The state denoting a processing instruction.
    static final int
    START
    The state denoting the start tag of an element.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    close()
    Close the XMLReader.
    Attributes
    getAttributes()
    Return the current attribute list.
    int
    getElementId()
    Return the current element ID.
    int
    getLineNumber()
    Return the current line number.
    String
    getLocalName()
    Return the current local name.
    QName
    getName()
    Return the current qualified name.
    Iterator
    getPrefixes()
    Return an iterator on all prefixes in scope, except for the default prefix.
    int
    getState()
    Return the current state of the XMLReader.
    String
    getURI()
    Return the current URI.
    String
    getURI(String prefix)
    Return the URI for the given prefix.
    String
    getValue()
    Return the current value.
    int
    next()
    Return the next state of the XMLReader.
    int
    nextContent()
     
    int
    nextElementContent()
    Return the next state of the XMLReader.
    XMLReader
    recordElement()
    Records the current element and leaves the reader positioned on its end tag.
    void
    skipElement()
    Skip all nodes up to the end tag of the element with the current element ID.
    void
    skipElement(int elementId)
    Skip all nodes up to the end tag of the element with the given element ID.

  • Field Details

    • BOF

      static final int BOF
      The initial state of a XMLReader.
      See Also:

    • START

      static final int START
      The state denoting the start tag of an element.
      See Also:

    • END

      static final int END
      The state denoting the end tag of an element.
      See Also:

    • CHARS

      static final int CHARS
      The state denoting the character content of an element.
      See Also:

    • PI

      static final int PI
      The state denoting a processing instruction.
      See Also:

    • EOF

      static final int EOF
      The state denoting that the end of the document has been reached.
      See Also:

  • Method Details

    • next

      int next()
      Return the next state of the XMLReader. The return value is one of: START, END, CHARS, PI, EOF.

    • nextContent

      int nextContent()

    • nextElementContent

      int nextElementContent()
      Return the next state of the XMLReader.

      Whitespace character content, processing instructions are ignored. Non-whitespace character content triggers an exception.

      The return value is one of: START, END, EOF.

    • getState

      int getState()
      Return the current state of the XMLReader.

    • getName

      QName getName()
      Return the current qualified name.

      Meaningful only when the state is one of: START, END.

    • getURI

      String getURI()
      Return the current URI.

      Meaningful only when the state is one of: START, END.

    • getLocalName

      String getLocalName()
      Return the current local name.

      Meaningful only when the state is one of: START, END, PI.

    • getAttributes

      Attributes getAttributes()
      Return the current attribute list.

      Meaningful only when the state is one of: START.

      The returned Attributes object belong to the XMLReader and is only guaranteed to be valid until the next() method is called, directly or indirectly.

    • getValue

      String getValue()
      Return the current value.

      Meaningful only when the state is one of: CHARS, PI.

    • getElementId

      int getElementId()
      Return the current element ID.

    • getLineNumber

      int getLineNumber()
      Return the current line number.

      Due to aggressive parsing, this value may be off by a few lines.

    • getURI

      String getURI(String prefix)
      Return the URI for the given prefix.

      If there is no namespace declaration in scope for the given prefix, return null.

    • getPrefixes

      Iterator getPrefixes()
      Return an iterator on all prefixes in scope, except for the default prefix.

    • recordElement

      XMLReader recordElement()
      Records the current element and leaves the reader positioned on its end tag.

      The XMLReader must be positioned on the start tag of the element. The returned reader will play back all events starting with the start tag of the element and ending with its end tag.

    • skipElement

      void skipElement()
      Skip all nodes up to the end tag of the element with the current element ID.

    • skipElement

      void skipElement(int elementId)
      Skip all nodes up to the end tag of the element with the given element ID.

    • close

      void close()
      Close the XMLReader.

      All subsequent calls to next() will return EOF.