Package com.broadleafcommerce.rulesengine.expression.service

Class SpelRuleEvaluationService

java.lang.Object

com.broadleafcommerce.rulesengine.expression.service.SpelRuleEvaluationService

All Implemented Interfaces:

RuleEvaluationService

public class SpelRuleEvaluationService
extends Object
implements RuleEvaluationService

Default implementation of RuleEvaluationService that takes the configured ExpressionParser to parse SpEL Expressions with caching for expressions and EvaluationContexts. Combined with CachingStdEvaluationContextFactory, supports SpEL expression evaluation with concrete objects or maps.

Expressions are cached based on the literal expression as the key while EvaluationContexts use the rootObject as the key.

Author:

Nathan Moore (nathanmoore).

See Also:

• SPeL documentation
• MapAccessor
• MapAccessor

Field Summary

Fields

Modifier and Type	Field	Description
protected final EvaluationContextFactory	evaluationContextFactory
protected static final Map<String,org.springframework.expression.Expression>	EXPRESSION_CACHE
protected final org.springframework.expression.ExpressionParser	spelParser

Constructor Summary

Constructors

Constructor	Description
SpelRuleEvaluationService(org.springframework.expression.ExpressionParser blSpelParser, EvaluationContextFactory blEvaluationContextFactory)

Method Summary

Modifier and Type	Method	Description
boolean	allMatch(Collection<String> rules, Object rootObject, ExpressionContext expressionContext)	Use to determine if the object matches all rules provided.
boolean	anyMatch(Collection<String> rules, Object rootObject, ExpressionContext expressionContext)	Use to determine if the object matches any rule provided.
boolean	evaluateRule(String rule, Object rootObject, ExpressionContext expressionContext)	Uses the configured expression parser to evaluate the rule against the root object.
<T> Iterable<T>	findAll(Collection<String> rules, Collection<T> rootObjects, ExpressionContext expressionContext)	Use to find all objects matching the rules provided.
<T> Optional<T>	findAny(Collection<String> rules, Collection<T> rootObjects, ExpressionContext expressionContext)	Use to find an object that matches the rules.
<T> Iterable<T>	findAnyN(Collection<String> rules, Collection<T> rootObjects, ExpressionContext expressionContext)	Use to find a subset of all objects matching the rules provided.
<T> Optional<T>	findFirst(Collection<String> rules, Collection<T> rootObjects, ExpressionContext expressionContext)	Use to find the first object that matches the rules.
<T> Iterable<T>	findFirstN(Collection<String> rules, Collection<T> rootObjects, ExpressionContext expressionContext)	Use to find a subset of all objects matching the rules provided.
protected org.springframework.expression.Expression	getExpressionFromCache(String rule, ExpressionContext expressionContext)
protected Optional<org.springframework.expression.ParserContext>	getParserContext(ExpressionContext expressionContext)
boolean	noneMatch(Collection<String> rules, Object rootObject, ExpressionContext expressionContext)	Use to determine if the object matches no provided rule.

Methods inherited from class java.lang.Object

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

Field Details

EXPRESSION_CACHE

protected static final Map<String,org.springframework.expression.Expression> EXPRESSION_CACHE

spelParser

protected final org.springframework.expression.ExpressionParser spelParser

evaluationContextFactory

protected final EvaluationContextFactory evaluationContextFactory

Constructor Details

SpelRuleEvaluationService

public SpelRuleEvaluationService(org.springframework.expression.ExpressionParser blSpelParser,
 EvaluationContextFactory blEvaluationContextFactory)

Method Details

evaluateRule

public boolean evaluateRule(String rule,
 Object rootObject,
 ExpressionContext expressionContext)

Uses the configured expression parser to evaluate the rule against the root object. If the rule is null or blank, this method returns true.

Specified by:

evaluateRule in interface RuleEvaluationService

Parameters:

rule - String representation of an expression

rootObject - Object to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

whether the object matches the rule

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

anyMatch

public boolean anyMatch(Collection<String> rules,
 Object rootObject,
 ExpressionContext expressionContext)

Use to determine if the object matches any rule provided.

Specified by:

anyMatch in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObject - Object to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

whether the object matches any rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

allMatch

public boolean allMatch(Collection<String> rules,
 Object rootObject,
 ExpressionContext expressionContext)

Use to determine if the object matches all rules provided.

Specified by:

allMatch in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObject - Object to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

whether the object matches all rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

noneMatch

public boolean noneMatch(Collection<String> rules,
 Object rootObject,
 ExpressionContext expressionContext)

Use to determine if the object matches no provided rule.

Specified by:

noneMatch in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObject - Object to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

whether the object matches no rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

findFirst

public <T> Optional<T> findFirst(Collection<String> rules,
 Collection<T> rootObjects,
 ExpressionContext expressionContext)

Use to find the first object that matches the rules. ExpressionContext.isMatchAnyRule() should be set to determine if returned object must match any or all rules.

Specified by:

findFirst in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObjects - Objects to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

the first object provided that matches the rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

findAny

public <T> Optional<T> findAny(Collection<String> rules,
 Collection<T> rootObjects,
 ExpressionContext expressionContext)

Use to find an object that matches the rules. ExpressionContext.isMatchAnyRule() should be set to determine if returned object must match any or all rules.

Specified by:

findAny in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObjects - Objects to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

an object provided that matches the rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

findAll

public <T> Iterable<T> findAll(Collection<String> rules,
 Collection<T> rootObjects,
 ExpressionContext expressionContext)

Use to find all objects matching the rules provided. ExpressionContext.isMatchAnyRule() should be set to determine if returned objects must match any or all rules.

Specified by:

findAll in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObjects - Objects to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

all objects provided that match rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

findAnyN

public <T> Iterable<T> findAnyN(Collection<String> rules,
 Collection<T> rootObjects,
 ExpressionContext expressionContext)

Description copied from interface: RuleEvaluationService

Use to find a subset of all objects matching the rules provided. The subset will consist of any 'n' objects found with 'n' being determined by ExpressionContext.getLimit(). ExpressionContext.isMatchAnyRule() should be set to determine if returned objects must match any or all rules.

Specified by:

findAnyN in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObjects - Objects to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

a subset of 'n' objects matching the rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

findFirstN

public <T> Iterable<T> findFirstN(Collection<String> rules,
 Collection<T> rootObjects,
 ExpressionContext expressionContext)

Description copied from interface: RuleEvaluationService

Use to find a subset of all objects matching the rules provided. The subset will consist of the first 'n' objects found with 'n' being determined by ExpressionContext.getLimit(). ExpressionContext.isMatchAnyRule() should be set to determine if returned objects must match any or all rules.

Specified by:

findFirstN in interface RuleEvaluationService

Parameters:

rules - String representations of expressions

rootObjects - Objects to evaluate the rule against

expressionContext - Relevant information required to evaluate an expression or group of expressions

Returns:

a subset of the first 'n' objects matching the rules

See Also:

• StandardExpressionContext.EMPTY_EXPRESSION_CONTEXT

getExpressionFromCache

protected org.springframework.expression.Expression getExpressionFromCache(String rule,
 ExpressionContext expressionContext)

getParserContext

protected Optional<org.springframework.expression.ParserContext> getParserContext(ExpressionContext expressionContext)