org.apache.nifi.attribute.expression.language

Class EmptyPreparedQuery

java.lang.Object

org.apache.nifi.attribute.expression.language.EmptyPreparedQuery

All Implemented Interfaces:

PreparedQuery

public class EmptyPreparedQuery
extends Object
implements PreparedQuery

Field Summary

Fields

Modifier and Type	Field and Description
private String	value

Constructor Summary

Constructors

Constructor and Description
EmptyPreparedQuery(String value)

Method Summary

Modifier and Type	Method and Description
String	evaluateExpressions(EvaluationContext evaluationContext, AttributeValueDecorator decorator)
Set<String>	getExplicitlyReferencedAttributes() Returns a Set of all attributes that are explicitly referenced by the Prepared Query.
VariableImpact	getVariableImpact() Returns a VariableImpact that can be used to determine whether or not a given variable impacts this Expression.
boolean	isExpressionLanguagePresent()

Methods inherited from class java.lang.Object

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

Field Detail

value

private final String value

Constructor Detail

EmptyPreparedQuery

EmptyPreparedQuery(String value)

Method Detail

evaluateExpressions

public String evaluateExpressions(EvaluationContext evaluationContext,
                                  AttributeValueDecorator decorator)
                           throws ProcessException

Specified by:

evaluateExpressions in interface PreparedQuery

Throws:

ProcessException

isExpressionLanguagePresent

public boolean isExpressionLanguagePresent()

Specified by:

isExpressionLanguagePresent in interface PreparedQuery

getVariableImpact

public VariableImpact getVariableImpact()

Description copied from interface: PreparedQuery

Returns a VariableImpact that can be used to determine whether or not a given variable impacts this Expression.

Specified by:

getVariableImpact in interface PreparedQuery

Returns:

a VariableImpact that can be used to determine whether or not a given variable impacts this Expression.

getExplicitlyReferencedAttributes

public Set<String> getExplicitlyReferencedAttributes()

Description copied from interface: PreparedQuery

Returns a Set of all attributes that are explicitly referenced by the Prepared Query. There are some expressions, however, such as ${allMatchingAttributes('a.*'):gt(4)} that reference multiple attributes, but those attributes' names cannot be determined a priori. As a result, those attributes will not be included in the returned set.

Specified by:

getExplicitlyReferencedAttributes in interface PreparedQuery

Returns:

a Set of all attributes that are explicitly referenced by the Prepared Query