org.jscience.architecture.traffic.xml
Class XMLLoader

java.lang.Object
  org.jscience.architecture.traffic.xml.XMLLoader

public class XMLLoader
extends java.lang.Object

This class can restore the state of the program from an XML file. It also provides methods which XMLSerializable objects can use to retrieve their child objects.

Field Summary

protected boolean	atEOF
protected XMLElement	nextElement
protected org.jscience.architecture.traffic.xml.XMLReader	reader
protected XMLStack	stack

Constructor Summary

protected	XMLLoader() Simple constructor
	XMLLoader(java.io.File file) Make a new XMLLoader which loads from a file
	XMLLoader(java.net.Socket socket) Make a new XMLLoader which load from a socket

Method Summary

void	close() Close this XMLLoader
void	doStackDump() This method is just for debugging
java.util.Enumeration	getEnumeration(XMLSerializable parent) Ignores the further child objects of this XMLSerializable /** Returns an enumeration of XML elements which can be loaded.
java.util.Enumeration	getEnumeration(XMLSerializable parent, java.lang.String tagName) Returns an enumeration of XML elements with a specific name which can be loaded.
XMLElement	getNextElement(XMLSerializable parent) Get the next element from the file
XMLElement	getNextElement(XMLSerializable parent, java.lang.String name) Get the next element from the file if it has a specific name
java.lang.String	getNextElementName()
boolean	hasNextElement(XMLSerializable parent) Checks if an XMLSerializable can get another element from the file
boolean	hasNextElement(XMLSerializable parent, java.lang.String name) Checks if an XMLSerializable can get an element with a specific name from the file.
void	load(XMLSerializable parent, XMLSerializable object) Load an XMLSerializable from the XML file
void	loadEnumeration(XMLSerializable parent, java.util.Enumeration o) Load an enumeration of XMLSerializables from the XML file
protected void	lookAhead() Fill the nextElement buffer if it is empty
protected XMLElement	pullNextElement() Tranfer the contents of the nextElement buffer to a XMLSerializable and fill the buffer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

reader

protected org.jscience.architecture.traffic.xml.XMLReader reader

nextElement

protected XMLElement nextElement

stack

protected XMLStack stack

atEOF

protected boolean atEOF

Constructor Detail

XMLLoader

protected XMLLoader()

Simple constructor

XMLLoader

public XMLLoader(java.io.File file)
          throws java.io.IOException,
                 XMLTreeException,
                 XMLInvalidInputException

Make a new XMLLoader which loads from a file

Parameters:

file - The file to load from

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is initializing the XML tree structure.

XMLInvalidInputException - If the XML file contains invalid values.

XMLLoader

public XMLLoader(java.net.Socket socket)
          throws java.io.IOException,
                 XMLTreeException,
                 XMLInvalidInputException

Make a new XMLLoader which load from a socket

Parameters:

file - The file to load from

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is initializing the XML tree structure.

XMLInvalidInputException - If the XML file contains invalid values.

Method Detail

load

public void load(XMLSerializable parent,
                 XMLSerializable object)
          throws XMLTreeException,
                 XMLInvalidInputException,
                 java.io.IOException

Load an XMLSerializable from the XML file

Parameters:

parent - The parent of this XMLSerializable

object - The XMLSerializable object itself

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is building the XML tree structure.

XMLInvalidInputException - If this XMLSerializable encounters invalid input or cannot load itself for another reason.

close

public void close()

Close this XMLLoader

loadEnumeration

public void loadEnumeration(XMLSerializable parent,
                            java.util.Enumeration o)
                     throws XMLTreeException,
                            XMLInvalidInputException,
                            java.io.IOException,
                            java.lang.ClassCastException

Load an enumeration of XMLSerializables from the XML file

Parameters:

parent - The parent of the XMLSerializables

o - The enumeration of XML serializables

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is building the XML tree structure.

XMLInvalidInputException - If one of the XMLSerializables encounters invalid input or cannot load itself for another reason.

java.lang.ClassCastException - If the enumeration contains an object that is not XMLSerializable

lookAhead

protected void lookAhead()
                  throws XMLTreeException,
                         java.io.IOException

Fill the nextElement buffer if it is empty

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is building the XML tree structure.

getNextElement

public XMLElement getNextElement(XMLSerializable parent)
                          throws XMLTreeException,
                                 java.io.IOException

Get the next element from the file

Parameters:

parent - The XMLSerializable which is asking for the next element

Returns:

The next XMLElement

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is building the XML tree structure or if the next element has another parent.

hasNextElement

public boolean hasNextElement(XMLSerializable parent)

Checks if an XMLSerializable can get another element from the file

Parameters:

parent - The XMLSerializable that wants to request the next element

Returns:

A boolean value which indicates if another element can be fetched.

getNextElement

public XMLElement getNextElement(XMLSerializable parent,
                                 java.lang.String name)
                          throws XMLTreeException,
                                 java.io.IOException

Get the next element from the file if it has a specific name

Parameters:

parent - The XMLSerializable which is asking for the next element

name - The name which the next element has to have

Returns:

The next XMLElement

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is building the XML tree structure or if the next element in the file has another name/parent.

hasNextElement

public boolean hasNextElement(XMLSerializable parent,
                              java.lang.String name)

Checks if an XMLSerializable can get an element with a specific name from the file.

Parameters:

parent - The XMLSerializable that wants to request the next element

name - The requested name

Returns:

A boolean value which indicates if an element with such a name can be fetched.

pullNextElement

protected XMLElement pullNextElement()
                              throws java.io.IOException,
                                     XMLTreeException

Tranfer the contents of the nextElement buffer to a XMLSerializable and fill the buffer.

Returns:

The XMLElement in the buffer

Throws:

java.io.IOException - If the XMLLoader cannot read from the XML file because of an IO error.

XMLTreeException - If something goes wrong while the parser is building the XML tree structure.

getNextElementName

public java.lang.String getNextElementName()

Returns:

The name of the XMLElement in the buffer, regardless of its parent. If the buffer is empty, then the return value is null.

getEnumeration

public java.util.Enumeration getEnumeration(XMLSerializable parent)

Ignores the further child objects of this XMLSerializable

/** Returns an enumeration of XML elements which can be loaded. More or less the enumeration form of getNextElement(parent). WARNING : using more than one of these enumerations simultaneously may result in unpredictable behaviour.

Parameters:

parent - The object which is requesting the enumeration

Returns:

An enumeration of XMLElements

getEnumeration

public java.util.Enumeration getEnumeration(XMLSerializable parent,
                                            java.lang.String tagName)

Returns an enumeration of XML elements with a specific name which can be loaded. More or less the enumeration form of getNextElement(parent,name). WARNING : using more than one of these enumerations simultaneously may result in unpredictable behaviour.

Parameters:

parent - The object which is requesting the enumeration

name - The requested name

Returns:

An enumeration of XMLElements

doStackDump

public void doStackDump()

This method is just for debugging