org.apache.nifi.attribute.expression.language

Class InvalidPreparedQuery

java.lang.Object

org.apache.nifi.attribute.expression.language.InvalidPreparedQuery

All Implemented Interfaces:

PreparedQuery

public class InvalidPreparedQuery
extends Object
implements PreparedQuery

An implementation of PreparedQuery that throws an AttributeExpressionLanguageException when attempting to evaluate the query. This allows a PreparedQuery to be created, even though it can't be evaluated.

Field Summary

Fields

Modifier and Type	Field and Description
private String	explanation
private String	query

Constructor Summary

Constructors

Constructor and Description
InvalidPreparedQuery(String query, String explanation)

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

query

private final String query

explanation

private final String explanation

Constructor Detail

InvalidPreparedQuery

public InvalidPreparedQuery(String query,
                            String explanation)

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