org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements
Class BaseElementProcessor

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.BaseElementProcessor

All Implemented Interfaces:

Component, LogEnabled, ElementProcessor, POIFSElementProcessor

Direct Known Subclasses:

EP_Bottom, EP_Default_, EP_Draft, EP_EvenIfOnlyStyles, EP_Footer, EP_Grid, EP_HCenter, EP_Header, EP_Left, EP_Monochrome, EP_Name, EP_Order, EP_Orientation, EP_Paper, EP_RepeatLeft, EP_RepeatTop, EP_Right, EP_Titles, EP_Top, EP_Type, EP_ValString, EP_Value, EP_VCenter, EPAttribute, EPAttributes, EPBottom, EPButton, EPCell, EPCellComment, EPCells, EPCheckbox, EPColInfo, EPCols, EPConstr, EPContent, EPDiagonal, EPFont, EPFooter, EPFrame, EPGeometry, EPHeader, EPItem, EPLabel, EPLeft, EPMargins, EPMaxCol, EPMaxRow, EPMerge, EPMergedRegions, EPName, EPNames, EPObjects, EPPrintInformation, EPRev_Diagonal, EPRight, EPRowInfo, EPRows, EPSelection, EPSelections, EPSheet, EPSheetName, EPSheetNameIndex, EPSheetObjectBonobo, EPSheetObjectFilled, EPSheets, EPSolver, EPStyle, EPStyleBorder, EPStyleRegion, EPStyles, EPSummary, EPTop, EPUIData, EPWorkbook, EPZoom

public abstract class BaseElementProcessor
extends AbstractLogEnabled
implements POIFSElementProcessor

The BaseElementProcessor class provides default behavior for classes that can handle a particular XML element's content. It is intended that all ElementProcessors should extend this class. This class is declared Abstract although it has no abstract methods. It can be used 'as is' for a no-op ElementProcessor, and an ElementProcessor that chooses to simply extend this class with no overrides will be a no-op ElementProcessor.

Version:

CVS $Id: BaseElementProcessor.html 1304258 2012-03-23 10:09:27Z ilgrosso $

Author:

Marc Johnson (marc_johnson27591@hotmail.com)

Field Summary

Fields inherited from interface org.apache.cocoon.components.elementprocessor.ElementProcessor

ROLE

Constructor Summary

protected

BaseElementProcessor(Attribute[] implied_attributes) Constructor

Method Summary

void	acceptCharacters(char[] data) The data provided in this method call comes from the corresponding XML element's contents.
void	acceptWhitespaceCharacters(char[] data) The data provided in this method call comes from the corresponding XML element's contents.
void	endProcessing() This is the last method call executed by the POIFSSerializer.
protected ElementProcessor	getAncestor(Class theclass) get the nearest ancestor that happens to be an instance of the specified class
protected Iterator	getAttributes()
protected org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.Cell	getCell() get the current cell we're working on.
protected String	getData()
protected org.apache.poi.poifs.filesystem.POIFSFileSystem	getFilesystem()
protected ElementProcessor	getParent()
protected org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.Sheet	getSheet() get the current sheet we're working on.
protected String	getValue(String name) Get the value of an attribute
protected org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.Workbook	getWorkbook() get the workbook we're working on.
void	initialize(Attribute[] attributes, ElementProcessor parent) The implementation should walk the array of attributes and perform appropriate actions based on that data.
void	setFilesystem(org.apache.poi.poifs.filesystem.POIFSFileSystem fs) Set the POIFSFileSystem for the element processor

Methods inherited from class org.apache.avalon.framework.logger.AbstractLogEnabled

enableLogging, getLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

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

Constructor Detail

BaseElementProcessor

protected BaseElementProcessor(Attribute[] implied_attributes)

Constructor

Parameters:

implied_attributes - an array of Attributes which might not appear in the initialization call because they are implied, and the SAX processor will not automatically generate them.

Method Detail

getAttributes

protected Iterator getAttributes()

Returns:

the Attributes managed by this ElementProcessor. May be empty, but never null

getValue

protected String getValue(String name)

Get the value of an attribute

Parameters:

name - the name of the attribute to look up

Returns:

the value of the specified attribute; will be null if the attribute doesn't exist

getFilesystem

protected org.apache.poi.poifs.filesystem.POIFSFileSystem getFilesystem()

Returns:

the POIFSFileSystem object

getParent

protected ElementProcessor getParent()

Returns:

the parent ElementProcessor; may be null

getAncestor

protected ElementProcessor getAncestor(Class theclass)

get the nearest ancestor that happens to be an instance of the specified class

Parameters:

theclass - the class we're looking for

Returns:

an ancestor of the specified class; null if no such ancestor exists

getData

protected String getData()

Returns:

the data, both regular characters and whitespace characters, collected so far

getWorkbook

protected org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.Workbook getWorkbook()
                                                                                             throws IOException

get the workbook we're working on. If it isn't in this instance, check the parent

Returns:

the workbook we're working on. Never null

Throws:

IOException - if the workbook is missing

getSheet

protected org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.Sheet getSheet()
                                                                                       throws IOException

get the current sheet we're working on. If it isn't in this instance, check the parent

Returns:

the current sheet we're working on. Never null

Throws:

IOException - if the sheet is missing

getCell

protected org.apache.cocoon.components.elementprocessor.impl.poi.hssf.elements.Cell getCell()
                                                                                     throws IOException

get the current cell we're working on. If it isn't in this instance, check the parent

Returns:

the current cell we're working on. Never null

Throws:

IOException - if the cell is missing

initialize

public void initialize(Attribute[] attributes,
                       ElementProcessor parent)
                throws IOException

The implementation should walk the array of attributes and perform appropriate actions based on that data. The array of attributes is guaranteed never to be null, but it can be empty. An implementation can expect code like this to work without throwing runtime exceptions:
for (int k = 0; k < attributes.length; k++)
{
Attribute attr = attributes[ k ];
// process attribute
}

NOTE: if the XML DTD or schema includes IMPLIED attributes for an element, those attributes are not included in the Attribute array - they're not in the data provided in the startElement call. The constructor for the ElementProcessor should set those implied attributes itself, and allow them to be overridden if the XML source provided explicit values for them.
The parent ElementProcessor is a reference to the ElementProcessor whose corresponding XML element contains this ElementProcessor's corresponding XML element. It will not be null unless this ElementProcessor's corresponding XML element is the top-level element in the XML document. Whether this ElementProcessor needs to establish a containment relationship with its parent or not, and whether it needs to do so at the beginning, middle, or end of its life cycle, are private matters left to the discretion of the individual ElementProcessor implementation. If the ElementProcessor needs to interact with its parent ElementProcessor, but is not ready to do so when the initialize method is called, it must cache the reference to its parent.

Specified by:

initialize in interface ElementProcessor

Parameters:

attributes - the array of Attribute instances; may be empty, will never be null

parent - the parent ElementProcessor; may be null

Throws:

IOException - if anything is wrong

acceptCharacters

public void acceptCharacters(char[] data)

The data provided in this method call comes from the corresponding XML element's contents. The array is guaranteed not to be null and will never be empty.
The POIFSSerializer will make 0 to many calls to this method; all such calls will occur after the initialize method is called and before the endProcessing method is called.
Calls to this method may be interleaved with calls to acceptWhitespaceCharacters. All calls to acceptCharacters and acceptWhitespaceCharacters are guaranteed to be in the same order as their data is in the element.

Specified by:

acceptCharacters in interface ElementProcessor

Parameters:

data - the character data

acceptWhitespaceCharacters

public void acceptWhitespaceCharacters(char[] data)

The data provided in this method call comes from the corresponding XML element's contents. The array is guaranteed not to be null and will never be empty.
The POIFSSerializer will make 0 to many calls to this method; all such calls will occur after the initialize method is called and before the endProcessing method is called.
Calls to this method may be interleaved with calls to acceptCharacters. All calls to acceptCharacters and acceptWhitespaceCharacters are guaranteed to be in the same order as their data is in the element.

Specified by:

acceptWhitespaceCharacters in interface ElementProcessor

Parameters:

data - the whitespace characters

endProcessing

public void endProcessing()
                   throws IOException

This is the last method call executed by the POIFSSerializer. When this method is called, the ElementProcessor should finish its work and perform its final interactions with its parent ElementProcessor and the filesystem, if necessary.
If the implementation cached the parent ElementProcessor reference, the filesystem reference, or both, when the initialize method was called, it should null out those references.

Specified by:

endProcessing in interface ElementProcessor

Throws:

IOException

setFilesystem

public void setFilesystem(org.apache.poi.poifs.filesystem.POIFSFileSystem fs)

Set the POIFSFileSystem for the element processor

Specified by:

setFilesystem in interface POIFSElementProcessor

Parameters:

fs - the POIFSFileSystem instance