Package weka.core.xml

Class XMLSerialization

java.lang.Object
weka.core.xml.XMLSerialization
All Implemented Interfaces:
RevisionHandler
Direct Known Subclasses:
XMLBasicSerialization
public class XMLSerialization extends Object implements RevisionHandler
With this class objects can be serialized to XML instead into a binary format. It uses introspection (cf. beans) to retrieve the data from the given object, i.e. it can only access beans-conform fields automatically.

The generic approach of writing data as XML can be overriden by adding custom methods for reading/writing in a derived class (cf. m_Properties, m_CustomMethods).
Custom read and write methods must have the same signature (and also be public!) as the readFromXML and writeToXML methods. Methods that apply to the naming rule read + property name are added automatically to the list of methods by the method XMLSerializationMethodHandler.addMethods(...).

Other properties that are not conform the bean set/get-methods have to be processed manually in a derived class (cf. readPostProcess(Object), writePostProcess(Object)).

For a complete XML serialization/deserialization have a look at the KOML class.

If a stored class has a constructor that takes a String to initialize (e.g. String or Double) then the content of the tag will used for the constructor, e.g. from 

 <object name="name" class="String" primitive="no">Smith</object>
"Smith" will be used to instantiate a String object as constructor argument.

Version:
$Revision: 13476 $
Author:
FracPete (fracpete at waikato dot ac dot nz)
See Also:

  • Field Details

  • Constructor Details

    • XMLSerialization

      public XMLSerialization() throws Exception
      initializes the serialization
      Throws:
      Exception - if initialization fails

  • Method Details

    • setSuppressWarnings

      public void setSuppressWarnings(boolean suppress)
      Set whether to suppress warning messages or not
      Parameters:
      suppress - true to suppress warnings

    • clear

      public void clear() throws Exception
      generates internally a new XML document and clears also the IgnoreList and the mappings for the Read/Write-Methods
      Throws:
      Exception - if something goes wrong

    • getVersion

      public String getVersion()
      returns the WEKA version with which the serialized object was created
      Returns:
      the current version
      See Also:

    • writeToXML

      public Element writeToXML(Element parent, Object o, String name) throws Exception
      adds the given Object to a DOM structure. (only public due to reflection).
      Note: overrideClassname(Object) is not invoked in case of arrays, since the array class could be a superclass, whereas the elements of the array can be specialized subclasses. In case of an array the method overrideClassname(String) is invoked, which searches for an exact match of the classname in the override hashtable.
      Parameters:
      parent - the parent of this object, e.g. the class this object is a member of
      o - the Object to describe in XML
      name - the name of the object
      Returns:
      the node that was created
      Throws:
      Exception - if the DOM creation fails
      See Also:
      • overrideClassname(Object)
      • overrideClassname(String)
      • m_ClassnameOverride

    • toXML

      public XMLDocument toXML(Object o) throws Exception
      extracts all accesible properties from the given object
      Parameters:
      o - the object to turn into an XML representation
      Returns:
      the generated DOM document
      Throws:
      Exception - if XML generation fails

    • readBooleanFromXML

      public boolean readBooleanFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readByteFromXML

      public byte readByteFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readCharFromXML

      public char readCharFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readDoubleFromXML

      public double readDoubleFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readFloatFromXML

      public float readFloatFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readIntFromXML

      public int readIntFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readLongFromXML

      public long readLongFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readShortFromXML

      public short readShortFromXML(Element node) throws Exception
      builds the primitive from the given DOM node.
      Parameters:
      node - the associated XML node
      Returns:
      the primitive created from the XML description
      Throws:
      Exception - if instantiation fails

    • readFromXML

      public Object readFromXML(Object o, String name, Element child) throws Exception
      adds the specific node to the object via a set method
      Parameters:
      o - the object to set a property
      name - the name of the object for which to set a property (only for information reasons)
      child - the value of the property to add
      Returns:
      the provided object, but augmented by the child
      Throws:
      Exception - if something goes wrong

    • readFromXML

      public Object readFromXML(Element node) throws Exception
      builds the object from the given DOM node. (only public due to reflection)
      Parameters:
      node - the associated XML node
      Returns:
      the instance created from the XML description
      Throws:
      Exception - if instantiation fails

    • fromXML

      public Object fromXML(Document document) throws Exception
      returns the given DOM document as an instance of the specified class
      Parameters:
      document - the parsed DOM document representing the object
      Returns:
      the XML as object
      Throws:
      Exception - if object instantiation fails

    • read

      public Object read(String xml) throws Exception
      parses the given XML string (can be XML or a filename) and returns an Object generated from the representation
      Parameters:
      xml - the xml to parse (if "<?xml" is not found then it is considered a file)
      Returns:
      the generated instance
      Throws:
      Exception - if something goes wrong with the parsing

    • read

      public Object read(File file) throws Exception
      parses the given file and returns a DOM document
      Parameters:
      file - the XML file to parse
      Returns:
      the parsed DOM document
      Throws:
      Exception - if something goes wrong with the parsing

    • read

      public Object read(InputStream stream) throws Exception
      parses the given stream and returns a DOM document
      Parameters:
      stream - the XML stream to parse
      Returns:
      the parsed DOM document
      Throws:
      Exception - if something goes wrong with the parsing

    • read

      public Object read(Reader reader) throws Exception
      parses the given reader and returns a DOM document
      Parameters:
      reader - the XML reader to parse
      Returns:
      the parsed DOM document
      Throws:
      Exception - if something goes wrong with the parsing

    • write

      public void write(String file, Object o) throws Exception
      writes the given object into the file
      Parameters:
      file - the filename to write to
      o - the object to serialize as XML
      Throws:
      Exception - if something goes wrong with the parsing

    • write

      public void write(File file, Object o) throws Exception
      writes the given object into the file
      Parameters:
      file - the filename to write to
      o - the object to serialize as XML
      Throws:
      Exception - if something goes wrong with the parsing

    • write

      public void write(OutputStream stream, Object o) throws Exception
      writes the given object into the stream
      Parameters:
      stream - the filename to write to
      o - the object to serialize as XML
      Throws:
      Exception - if something goes wrong with the parsing

    • write

      public void write(Writer writer, Object o) throws Exception
      writes the given object into the writer
      Parameters:
      writer - the filename to write to
      o - the object to serialize as XML
      Throws:
      Exception - if something goes wrong with the parsing

    • main

      public static void main(String[] args) throws Exception
      for testing only. if the first argument is a filename with ".xml" as extension it tries to generate an instance from the XML description and does a toString() of the generated object.
      Throws:
      Exception

    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Returns:
      the revision