org.apache.nifi.processors.standard

Class EvaluateXQuery

java.lang.Object

org.apache.nifi.components.AbstractConfigurableComponent

org.apache.nifi.processor.AbstractSessionFactoryProcessor

org.apache.nifi.processor.AbstractProcessor

org.apache.nifi.processors.standard.EvaluateXQuery

All Implemented Interfaces:

ConfigurableComponent, Processor

@EventDriven
 @SideEffectFree
 @SupportsBatching
 @Tags(value={"XML","evaluate","XPath","XQuery"})
 @InputRequirement(value=INPUT_REQUIRED)
 @CapabilityDescription(value="Evaluates one or more XQueries against the content of a FlowFile.  The results of those XQueries are assigned to FlowFile Attributes or are written to the content of the FlowFile itself, depending on configuration of the Processor.  XQueries are entered by adding user-defined properties; the name of the property maps to the Attribute Name into which the result will be placed (if the Destination is \'flowfile-attribute\'; otherwise, the property name is ignored).  The value of the property must be a valid XQuery.  If the XQuery returns more than one result, new attributes or FlowFiles (for Destinations of \'flowfile-attribute\' or \'flowfile-content\' respectively) will be created for each result (attributes will have a \'.n\' one-up number appended to the specified attribute name).  If any provided XQuery returns a result, the FlowFile(s) will be routed to \'matched\'. If no provided XQuery returns a result, the FlowFile will be routed to \'unmatched\'.  If the Destination is \'flowfile-attribute\' and the XQueries matche nothing, no attributes will be applied to the FlowFile.")
 @WritesAttribute(attribute="user-defined",
                 description="This processor adds user-defined attributes if the <Destination> property is set to flowfile-attribute .")
 @DynamicProperty(name="A FlowFile attribute(if <Destination> is set to \'flowfile-attribute\'",
                 value="An XQuery",
                 description="If <Destination>=\'flowfile-attribute\' then the FlowFile attribute is set to the result of the XQuery.  If <Destination>=\'flowfile-content\' then the FlowFile content is set to the result of the XQuery.")
public class EvaluateXQuery
extends AbstractProcessor

Field Summary

Fields

Modifier and Type	Field and Description
static PropertyDescriptor	DESTINATION
static java.lang.String	DESTINATION_ATTRIBUTE
static java.lang.String	DESTINATION_CONTENT
static java.lang.String	OUTPUT_METHOD_HTML
static java.lang.String	OUTPUT_METHOD_TEXT
static java.lang.String	OUTPUT_METHOD_XML
static Relationship	REL_FAILURE
static Relationship	REL_MATCH
static Relationship	REL_NO_MATCH
static java.lang.String	UTF8
static PropertyDescriptor	VALIDATE_DTD
static PropertyDescriptor	XML_OUTPUT_INDENT
static PropertyDescriptor	XML_OUTPUT_METHOD
static PropertyDescriptor	XML_OUTPUT_OMIT_XML_DECLARATION

Constructor Summary

Constructors

Constructor and Description
EvaluateXQuery()

Method Summary

Modifier and Type	Method and Description
protected java.util.Collection<ValidationResult>	customValidate(ValidationContext context) Allows subclasses to perform their own validation on the already set properties.
java.util.Set<Relationship>	getRelationships()
protected PropertyDescriptor	getSupportedDynamicPropertyDescriptor(java.lang.String propertyDescriptorName) Used to allow subclasses to determine what PropertyDescriptor if any to use when a property is requested for which a descriptor is not already registered.
protected java.util.List<PropertyDescriptor>	getSupportedPropertyDescriptors() Allows subclasses to register which property descriptor objects are supported.
protected void	init(ProcessorInitializationContext context) Provides subclasses the ability to perform initialization logic
void	onTrigger(ProcessContext context, ProcessSession session)

Methods inherited from class org.apache.nifi.processor.AbstractProcessor

onTrigger

Methods inherited from class org.apache.nifi.processor.AbstractSessionFactoryProcessor

getControllerServiceLookup, getIdentifier, getLogger, getNodeTypeProvider, initialize, isConfigurationRestored, isScheduled, toString, updateConfiguredRestoredTrue, updateScheduledFalse, updateScheduledTrue

Methods inherited from class org.apache.nifi.components.AbstractConfigurableComponent

equals, getPropertyDescriptor, getPropertyDescriptors, hashCode, onPropertyModified, validate

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.nifi.components.ConfigurableComponent

getPropertyDescriptor, getPropertyDescriptors, onPropertyModified, validate

Field Detail

DESTINATION_ATTRIBUTE

public static final java.lang.String DESTINATION_ATTRIBUTE

See Also:

Constant Field Values

DESTINATION_CONTENT

public static final java.lang.String DESTINATION_CONTENT

See Also:

Constant Field Values

OUTPUT_METHOD_XML

public static final java.lang.String OUTPUT_METHOD_XML

See Also:

Constant Field Values

OUTPUT_METHOD_HTML

public static final java.lang.String OUTPUT_METHOD_HTML

See Also:

Constant Field Values

OUTPUT_METHOD_TEXT

public static final java.lang.String OUTPUT_METHOD_TEXT

See Also:

Constant Field Values

UTF8

public static final java.lang.String UTF8

See Also:

Constant Field Values

DESTINATION

public static final PropertyDescriptor DESTINATION

XML_OUTPUT_METHOD

public static final PropertyDescriptor XML_OUTPUT_METHOD

XML_OUTPUT_OMIT_XML_DECLARATION

public static final PropertyDescriptor XML_OUTPUT_OMIT_XML_DECLARATION

XML_OUTPUT_INDENT

public static final PropertyDescriptor XML_OUTPUT_INDENT

VALIDATE_DTD

public static final PropertyDescriptor VALIDATE_DTD

REL_MATCH

public static final Relationship REL_MATCH

REL_NO_MATCH

public static final Relationship REL_NO_MATCH

REL_FAILURE

public static final Relationship REL_FAILURE

Constructor Detail

EvaluateXQuery

public EvaluateXQuery()

Method Detail

init

protected void init(ProcessorInitializationContext context)

Description copied from class: AbstractSessionFactoryProcessor

Provides subclasses the ability to perform initialization logic

Overrides:

init in class AbstractSessionFactoryProcessor

Parameters:

context - in which to perform initialization

customValidate

protected java.util.Collection<ValidationResult> customValidate(ValidationContext context)

Description copied from class: AbstractConfigurableComponent

Allows subclasses to perform their own validation on the already set properties. Since each property is validated as it is set this allows validation of groups of properties together. Default return is an empty set. This method will be called only when it has been determined that all property values are valid according to their corresponding PropertyDescriptor's validators.

Overrides:

customValidate in class AbstractConfigurableComponent

Parameters:

context - provides a mechanism for obtaining externally managed values, such as property values and supplies convenience methods for operating on those values

Returns:

Collection of ValidationResult objects that will be added to any other validation findings - may be null

getRelationships

public java.util.Set<Relationship> getRelationships()

Specified by:

getRelationships in interface Processor

Overrides:

getRelationships in class AbstractSessionFactoryProcessor

Returns:

Set of all relationships this processor expects to transfer a flow file to. An empty set indicates this processor does not have any destination relationships. Guaranteed non null.

getSupportedPropertyDescriptors

protected java.util.List<PropertyDescriptor> getSupportedPropertyDescriptors()

Description copied from class: AbstractConfigurableComponent

Allows subclasses to register which property descriptor objects are supported. Default return is an empty set.

Overrides:

getSupportedPropertyDescriptors in class AbstractConfigurableComponent

Returns:

PropertyDescriptor objects this processor currently supports

getSupportedDynamicPropertyDescriptor

protected PropertyDescriptor getSupportedDynamicPropertyDescriptor(java.lang.String propertyDescriptorName)

Description copied from class: AbstractConfigurableComponent

Used to allow subclasses to determine what PropertyDescriptor if any to use when a property is requested for which a descriptor is not already registered. By default this method simply returns a null descriptor. By overriding this method processor implementations can support dynamic properties since this allows them to register properties on demand. It is acceptable for a dynamically generated property to indicate it is required so long as it is understood it is only required once set. Dynamic properties by definition cannot be required until used.

This method should be side effect free in the subclasses in terms of how often it is called for a given property name because there is guarantees how often it will be called for a given property name.

Default is null.

Overrides:

getSupportedDynamicPropertyDescriptor in class AbstractConfigurableComponent

Parameters:

propertyDescriptorName - used to lookup if any property descriptors exist for that name

Returns:

new property descriptor if supported

onTrigger

public void onTrigger(ProcessContext context,
                      ProcessSession session)

Specified by:

onTrigger in class AbstractProcessor