org.apache.cocoon.forms.util
Class DomHelper

java.lang.Object
  extended byorg.apache.cocoon.forms.util.DomHelper

public class DomHelper
extends Object

Helper class to create and retrieve information from DOM-trees. It provides some functionality comparable to what's found in Avalon's Configuration objects. These lasts one could however not be used by Cocoon Forms because they don't provide an accurate model of an XML file (no mixed content, no namespaced attributes, no namespace declarations, ...).

This class depends specifically on the Xerces DOM implementation to be able to provide information about the location of elements in their source XML file. See the getLocation(Element) method.

Version:
$Id: DomHelper.html 1304280 2012-03-23 11:18:01Z ilgrosso $

Field Summary
static String XMLNS_URI
           
 
Constructor Summary
DomHelper()
           
 
Method Summary
static XMLizable compileElementContent(Element element)
          Returns the content of the given Element as an object implementing the XMLizable interface.
static String getAttribute(Element element, String attributeName)
          Returns the value of an element's attribute, but throws an exception if the element has no such attribute.
static String getAttribute(Element element, String attributeName, String defaultValue)
          Returns the value of an element's attribute, or a default value if the element has no such attribute.
static boolean getAttributeAsBoolean(Element element, String attributeName, boolean defaultValue)
           
static int getAttributeAsInteger(Element element, String attributeName)
           
static int getAttributeAsInteger(Element element, String attributeName, int defaultValue)
           
static Element getChildElement(Element element, String namespace, String localName)
          Returns the first child element with the given namespace and localName, or null if there is no such element.
static Element getChildElement(Element element, String namespace, String localName, boolean required)
          Returns the first child element with the given namespace and localName, or null if there is no such element and required flag is unset or throws an Exception if the "required" flag is set.
static Element[] getChildElements(Element element, String namespace)
          Returns all Element children of an Element that belong to the given namespace.
static Element[] getChildElements(Element element, String namespace, String localName)
          Returns all Element children of an Element that belong to the given namespace and have the given local name.
static int getColumnLocation(Element element)
           
static String getElementText(Element element)
           
static Map getInheritedNSDeclarations(Element elm)
           
static int getLineLocation(Element element)
           
static Map getLocalNSDeclarations(Element elm)
           
static String getLocation(Element element)
          Retrieves the location of an element node in the source file from which the Document was created.
static org.apache.cocoon.util.location.Location getLocationObject(Element element)
           
static String getSystemIdLocation(Element element)
           
static Document parse(InputSource inputSource, org.apache.cocoon.core.xml.SAXParser parser)
          Creates a W3C Document that remembers the location of each element in the source file.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

XMLNS_URI

public static final String XMLNS_URI
See Also:
Constant Field Values
Constructor Detail

DomHelper

public DomHelper()
Method Detail

getLocationObject

public static org.apache.cocoon.util.location.Location getLocationObject(Element element)

getLocation

public static String getLocation(Element element)
Retrieves the location of an element node in the source file from which the Document was created. This will only work for Document's created with the method #parse(InputSource, ServiceManager) of this class.


getSystemIdLocation

public static String getSystemIdLocation(Element element)

getLineLocation

public static int getLineLocation(Element element)

getColumnLocation

public static int getColumnLocation(Element element)

getChildElements

public static Element[] getChildElements(Element element,
                                         String namespace)
Returns all Element children of an Element that belong to the given namespace.


getChildElements

public static Element[] getChildElements(Element element,
                                         String namespace,
                                         String localName)
Returns all Element children of an Element that belong to the given namespace and have the given local name.


getChildElement

public static Element getChildElement(Element element,
                                      String namespace,
                                      String localName)
Returns the first child element with the given namespace and localName, or null if there is no such element.


getChildElement

public static Element getChildElement(Element element,
                                      String namespace,
                                      String localName,
                                      boolean required)
                               throws FormsException
Returns the first child element with the given namespace and localName, or null if there is no such element and required flag is unset or throws an Exception if the "required" flag is set.

Throws:
FormsException

getAttribute

public static String getAttribute(Element element,
                                  String attributeName)
                           throws FormsException
Returns the value of an element's attribute, but throws an exception if the element has no such attribute.

Throws:
FormsException

getAttribute

public static String getAttribute(Element element,
                                  String attributeName,
                                  String defaultValue)
Returns the value of an element's attribute, or a default value if the element has no such attribute.


getAttributeAsInteger

public static int getAttributeAsInteger(Element element,
                                        String attributeName)
                                 throws FormsException
Throws:
FormsException

getAttributeAsInteger

public static int getAttributeAsInteger(Element element,
                                        String attributeName,
                                        int defaultValue)
                                 throws FormsException
Throws:
FormsException

getAttributeAsBoolean

public static boolean getAttributeAsBoolean(Element element,
                                            String attributeName,
                                            boolean defaultValue)

getElementText

public static String getElementText(Element element)

compileElementContent

public static XMLizable compileElementContent(Element element)
Returns the content of the given Element as an object implementing the XMLizable interface. Practically speaking, the implementation uses the SaxBuffer class. The XMLizable object will be a standalone blurb of SAX events, not producing start/endDocument calls and containing all necessary namespace declarations.


parse

public static Document parse(InputSource inputSource,
                             org.apache.cocoon.core.xml.SAXParser parser)
                      throws SAXException,
                             IOException
Creates a W3C Document that remembers the location of each element in the source file. The location of element nodes can then be retrieved using the getLocation(Element) method.

Parameters:
inputSource - the inputSource to read the document from
Throws:
SAXException
IOException

getLocalNSDeclarations

public static Map getLocalNSDeclarations(Element elm)

getInheritedNSDeclarations

public static Map getInheritedNSDeclarations(Element elm)


Copyright 1999-2008 The Apache Software Foundation. All Rights Reserved.