org.apache.excalibur.xml.xpath
Class AbstractProcessorImpl

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.excalibur.xml.xpath.AbstractProcessorImpl

All Implemented Interfaces:

Component, Configurable, LogEnabled, PrefixResolver, XPathProcessor

Direct Known Subclasses:

JaxenProcessorImpl, Saxon8ProcessorImpl, XPathProcessorImpl

public abstract class AbstractProcessorImpl
extends AbstractLogEnabled
implements XPathProcessor, Configurable, PrefixResolver, Component

This class defines base class for the implementations of the XPathProcessor component. Provides implementation of the PrefixResolver and common implementation of five selectXXX methods.

Version:

CVS $Revision: 1.4 $ $Date: 2004/02/28 11:47:15 $ $Author: cziegeler $

Author:

Avalon Development Team

Field Summary

Fields inherited from interface org.apache.excalibur.xml.xpath.XPathProcessor

ROLE

Constructor Summary

AbstractProcessorImpl()

Method Summary

void	configure(Configuration configuration)
boolean	evaluateAsBoolean(org.w3c.dom.Node contextNode, String str) Evaluate XPath expression within a context.
abstract boolean	evaluateAsBoolean(org.w3c.dom.Node contextNode, String str, PrefixResolver resolver) Evaluate XPath expression within a context.
Number	evaluateAsNumber(org.w3c.dom.Node contextNode, String str) Evaluate XPath expression within a context.
abstract Number	evaluateAsNumber(org.w3c.dom.Node contextNode, String str, PrefixResolver resolver) Evaluate XPath expression within a context.
String	evaluateAsString(org.w3c.dom.Node contextNode, String str) Evaluate XPath expression within a context.
abstract String	evaluateAsString(org.w3c.dom.Node contextNode, String str, PrefixResolver resolver) Evaluate XPath expression within a context.
String	prefixToNamespace(String prefix) Given a namespace prefix, return the corresponding namespace URI, or null if the namespace prefix is not known.
org.w3c.dom.NodeList	selectNodeList(org.w3c.dom.Node contextNode, String str) Use an XPath string to select a nodelist.
abstract org.w3c.dom.NodeList	selectNodeList(org.w3c.dom.Node contextNode, String str, PrefixResolver resolver) Use an XPath string to select a nodelist.
org.w3c.dom.Node	selectSingleNode(org.w3c.dom.Node contextNode, String str) Use an XPath string to select a single node.
abstract org.w3c.dom.Node	selectSingleNode(org.w3c.dom.Node contextNode, String str, PrefixResolver resolver) Use an XPath string to select a single node.

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

AbstractProcessorImpl

public AbstractProcessorImpl()

Method Detail

configure

public void configure(Configuration configuration)
               throws ConfigurationException

Specified by:

configure in interface Configurable

Throws:

ConfigurationException

selectSingleNode

public org.w3c.dom.Node selectSingleNode(org.w3c.dom.Node contextNode,
                                         String str)

Use an XPath string to select a single node. XPath namespace prefixes are resolved from the context node, which may not be what you want (see the next method).

Specified by:

selectSingleNode in interface XPathProcessor

Parameters:

contextNode - The node to start searching from.

str - A valid XPath string.

Returns:

The first node found that matches the XPath, or null.

selectNodeList

public org.w3c.dom.NodeList selectNodeList(org.w3c.dom.Node contextNode,
                                           String str)

Use an XPath string to select a nodelist. XPath namespace prefixes are resolved from the contextNode.

Specified by:

selectNodeList in interface XPathProcessor

Parameters:

contextNode - The node to start searching from.

str - A valid XPath string.

Returns:

A NodeList, should never be null.

evaluateAsBoolean

public boolean evaluateAsBoolean(org.w3c.dom.Node contextNode,
                                 String str)

Evaluate XPath expression within a context.

Specified by:

evaluateAsBoolean in interface XPathProcessor

Parameters:

contextNode - The context node.

str - A valid XPath string.

Returns:

expression result as boolean.

evaluateAsNumber

public Number evaluateAsNumber(org.w3c.dom.Node contextNode,
                               String str)

Evaluate XPath expression within a context.

Specified by:

evaluateAsNumber in interface XPathProcessor

Parameters:

contextNode - The context node.

str - A valid XPath string.

Returns:

expression result as number.

evaluateAsString

public String evaluateAsString(org.w3c.dom.Node contextNode,
                               String str)

Evaluate XPath expression within a context.

Specified by:

evaluateAsString in interface XPathProcessor

Parameters:

contextNode - The context node.

str - A valid XPath string.

Returns:

expression result as string.

evaluateAsBoolean

public abstract boolean evaluateAsBoolean(org.w3c.dom.Node contextNode,
                                          String str,
                                          PrefixResolver resolver)

Evaluate XPath expression within a context.

Specified by:

evaluateAsBoolean in interface XPathProcessor

Parameters:

contextNode - The context node.

str - A valid XPath string.

resolver - a PrefixResolver, used for resolving namespace prefixes

Returns:

expression result as boolean.

evaluateAsNumber

public abstract Number evaluateAsNumber(org.w3c.dom.Node contextNode,
                                        String str,
                                        PrefixResolver resolver)

Evaluate XPath expression within a context.

Specified by:

evaluateAsNumber in interface XPathProcessor

Parameters:

contextNode - The context node.

str - A valid XPath string.

resolver - a PrefixResolver, used for resolving namespace prefixes

Returns:

expression result as number.

evaluateAsString

public abstract String evaluateAsString(org.w3c.dom.Node contextNode,
                                        String str,
                                        PrefixResolver resolver)

Evaluate XPath expression within a context.

Specified by:

evaluateAsString in interface XPathProcessor

Parameters:

contextNode - The context node.

str - A valid XPath string.

resolver - a PrefixResolver, used for resolving namespace prefixes

Returns:

expression result as string.

selectSingleNode

public abstract org.w3c.dom.Node selectSingleNode(org.w3c.dom.Node contextNode,
                                                  String str,
                                                  PrefixResolver resolver)

Use an XPath string to select a single node.

Specified by:

selectSingleNode in interface XPathProcessor

Parameters:

contextNode - The node to start searching from.

str - A valid XPath string.

resolver - a PrefixResolver, used for resolving namespace prefixes

Returns:

The first node found that matches the XPath, or null.

selectNodeList

public abstract org.w3c.dom.NodeList selectNodeList(org.w3c.dom.Node contextNode,
                                                    String str,
                                                    PrefixResolver resolver)

Use an XPath string to select a nodelist.

Specified by:

selectNodeList in interface XPathProcessor

Parameters:

contextNode - The node to start searching from.

str - A valid XPath string.

resolver - a PrefixResolver, used for resolving namespace prefixes

Returns:

A List, should never be null.

prefixToNamespace

public String prefixToNamespace(String prefix)

Description copied from interface: PrefixResolver

Given a namespace prefix, return the corresponding namespace URI, or null if the namespace prefix is not known.

Specified by:

prefixToNamespace in interface PrefixResolver