WireBox AOP — Aspect-Oriented Programming

When to Use This Skill

Use this skill when:

• Adding cross-cutting concerns (logging, transactions, security, caching, tracing) to methods without modifying them
• Creating reusable method interceptors (aspects)
• Using the built-in CFTransaction, HibernateTransaction, or MethodLogger aspects
• Binding aspects to classes/methods via DSL or self-binding annotations

Applies to both standalone WireBox and ColdBox applications.

Language Mode Reference

Examples use BoxLang (.bx) / CFML script syntax. Adapt for your target language:

Concept	BoxLang (.bx)	CFML (.cfc)
Class declaration	class [extends="..."] {	component [extends="..."] {
DI annotation	@inject above property name="svc";	property name="svc" inject="svc";

---

AOP Vocabulary

Term	Definition
Aspect	A modularized cross-cutting concern (e.g., logging, transactions)
Target Object	The object whose methods will be intercepted
Join Point	A method execution point where an aspect is applied
Advice	The action taken at a join point (before, after, or around)
AOP Proxy	The runtime proxy wrapping the original method

---

AOP Namespaces

// ColdBox application
coldbox.system.aop

// Standalone WireBox
wirebox.system.aop

WireBox AOP is implemented as a WireBox listener called the Mixer. It transforms objects after DI is complete and is fully decoupled from WireBox internals.

---

Step 1: Activate the AOP Engine

Register the Mixer listener in your WireBox binder:

Standalone WireBox

// config/WireBox.bx (or .cfc)
class extends="wirebox.system.ioc.config.Binder" {

    function configure() {
        wirebox = {
            listeners : [
                {
                    class      : "wirebox.system.aop.Mixer",
                    properties : {
                        // Where to write generated UDF stubs (disk or memory)
                        generationPath   : "/wirebox/system/aop/tmp",
                        // Reload class match dict on each request (dev only)
                        classMatchReload : false
                    }
                }
            ]
        }
    }
}

ColdBox Application

In ColdBox, use the coldbox.system.aop.Mixer namespace:

// config/WireBox.bx
class extends="coldbox.system.ioc.config.ColdBoxBinder" {

    function configure() {
        wirebox = {
            listeners : [
                {
                    class      : "coldbox.system.aop.Mixer",
                    properties : {
                        generationPath   : "/wirebox/system/aop/tmp",
                        classMatchReload : false
                    }
                }
            ]
        }

        // Register and bind aspects here
    }
}

Alternatively, register the Mixer as a ColdBox interceptor in config/ColdBox.cfc:

interceptors = [
    { class: "coldbox.system.aop.Mixer", name: "AOPMixer", properties: {} }
]

---

Step 2: Create an Aspect

An aspect must implement wirebox.system.aop.MethodInterceptor (or coldbox.system.aop.MethodInterceptor in ColdBox):

// models/aspects/MethodLoggerAspect.bx
class implements="wirebox.system.aop.MethodInterceptor" {

    // Aspects support full WireBox DI
    @inject "logbox:logger:{this}"
    property name="log";

    function init( boolean logResults = true ) {
        variables.logResults = arguments.logResults
        return this
    }

    /**
     * The single entry point for all AOP advice.
     * Implement before/around/after logic here.
     * You MUST call invocation.proceed() to execute the real method.
     */
    function invokeMethod( required invocation ) {
        var target  = arguments.invocation.getTargetName()
        var method  = arguments.invocation.getMethod()
        var args    = arguments.invocation.getArgs()
        var debug   = "target=#target#, method=#method#, args=#serializeJSON(args)#"

        // BEFORE advice
        log.debug( "BEFORE: #debug#" )

        // AROUND — proceed to the real method (or next aspect in chain)
        var result = arguments.invocation.proceed()

        // AFTER advice
        if ( !isNull( result ) && variables.logResults ) {
            log.debug( "AFTER: #debug#, result=#serializeJSON(result)#" )
        }

        return result ?: javaCast( "null", "" )
    }
}

Aspect Rules

• Always call invocation.proceed() unless you intentionally want to short-circuit the method (e.g., a security aspect that blocks access).
• If the method has a return value, return the result of proceed().
• Aspects are WireBox-managed objects — full DI is available.
• Multiple aspects can be chained on the same join point; execution follows registration order.

---

Step 3: Register the Aspect

In the WireBox binder, declare the aspect mapping using mapAspect():

// Register an aspect — auto-discovers classMatcher/methodMatcher annotations
mapAspect( "MethodLogger" ).to( "models.aspects.MethodLoggerAspect" )

// Disable auto-binding (self-binding annotations ignored)
mapAspect( aspect="MethodLogger", autoBind=false ).to( "models.aspects.MethodLoggerAspect" )

---

Step 4: Bind the Aspect to Classes and Methods

Use bindAspect() with the Matcher DSL to declare what to intercept:

// Log all save() calls on UserService
bindAspect(
    classes  : match().mappings( "UserService" ),
    methods  : match().methods( "save" ),
    aspects  : "MethodLogger"
)

// Transaction on any method annotated @transactional
bindAspect(
    classes  : match().any(),
    methods  : match().annotatedWith( "transactional" ),
    aspects  : "CFTransaction"
)

// Multiple aspects on regex-matched service classes
bindAspect(
    classes  : match().regex( ".*Service$" ),
    methods  : match().any(),
    aspects  : "MethodLogger,SecurityAspect"
)

---

Matcher DSL

The match() convenience method in the binder creates a wirebox.system.aop.Matcher instance. Chain these methods:

Class Matchers

Method	Description
any()	Matches all classes
mappings( mappings )	Match specific mapping names (list or array)
instanceOf( classPath )	Match if class isInstanceOf(classPath)
annotatedWith( annotation [, value] )	Match classes with an annotation (optionally matching value)
regex( pattern )	Match CFC path against a regular expression

Method Matchers

Method	Description
any()	Matches all methods
methods( names )	Match specific method names (list or array)
annotatedWith( annotation [, value] )	Match methods with an annotation
returns( type )	Match methods by return type
regex( pattern )	Match method names against a regular expression

Logical Combinators

Method	Description
andMatch( matcher )	AND two matchers together
orMatch( matcher )	OR two matchers together

// Only public void service methods
bindAspect(
    classes : match().regex( ".*Service$" ).andMatch( match().annotatedWith( "monitored" ) ),
    methods : match().returns( "void" ),
    aspects : "MetricsAspect"
)

---

Auto-Aspect Binding

Let the aspect declare its own class/method matchers via annotations — no bindAspect() call needed:

/**
 * @classMatcher any
 * @methodMatcher annotatedWith:transactional
 */
class name="TransactionAspect"
      implements="wirebox.system.aop.MethodInterceptor" {

    function invokeMethod( required invocation ) {
        transaction {
            return arguments.invocation.proceed()
        }
    }
}

Register it — WireBox detects the annotations and binds automatically:

mapAspect( "TransactionAspect" ).to( "models.aspects.TransactionAspect" )

Override the self-binding when needed:

mapAspect( aspect="TransactionAspect", autoBind=false ).to( "models.aspects.TransactionAspect" )
bindAspect( classes=match().mappings( "OrderService" ), methods=match().regex( "^save" ), aspects="TransactionAspect" )

classMatcher Annotation DSL Values

Value	Description
any	Any class
annotatedWith:{annotation}	Class has annotation present
annotatedWith:{annotation}:{value}	Class has annotation with specific value
mappings:{name,name,...}	Specific named mappings
instanceOf:{classPath}	Class is an instance of classPath
regex:{pattern}	Class path matches regex

methodMatcher Annotation DSL Values

Value	Description
any	Any method
annotatedWith:{annotation}	Method has annotation present
annotatedWith:{annotation}:{value}	Method has annotation with specific value
methods:{name,name,...}	Specific method names
returns:{type}	Methods returning a specific type
regex:{pattern}	Method name matches regex

---

MethodInvocation API

The invocation argument passed to invokeMethod exposes:

Method	Description
getMethod()	Name of the intercepted method (join point)
getMethodMetadata()	Struct of the method's CFC metadata (annotations)
getArgs()	Current argument collection (struct)
setArgs( args )	Override the argument collection before proceeding
getTarget()	Reference to the target object
getTargetName()	Name (mapping ID) of the target object
getTargetMapping()	The WireBox mapping object (has extra attributes etc.)
proceed()	Execute the real method or the next aspect in chain

function invokeMethod( required invocation ) {
    // Read a method annotation to decide behavior
    var meta = arguments.invocation.getMethodMetadata()
    if ( structKeyExists( meta, "secured" ) ) {
        if ( !variables.securityService.isLoggedIn() ) {
            throw( type="SecurityException", message="Not authorized" )
        }
    }

    // Modify arguments before the real call
    var args    = arguments.invocation.getArgs()
    args.auditUser = variables.securityService.getCurrentUser()
    arguments.invocation.setArgs( args )

    return arguments.invocation.proceed()
}

---

Built-In Aspects

WireBox ships with three ready-to-use aspects in wirebox.system.aop.aspects (or coldbox.system.aop.aspects):

CFTransaction

Wraps methods in a ColdFusion transaction {} block. Self-binding: matches any class, methods annotated @transactional.

mapAspect( "CFTransaction" ).to( "coldbox.system.aop.aspects.CFTransaction" )

// Now annotate any method with @transactional
class name="OrderService" {

    function placeOrder( required order ) transactional {
        variables.orderRepository.save( arguments.order )
        variables.inventoryService.deduct( arguments.order.getItems() )
    }
}

HibernateTransaction

Wraps methods in a native Hibernate transaction block. Same self-binding pattern as CFTransaction.

mapAspect( "HibernateTransaction" ).to( "coldbox.system.aop.aspects.HibernateTransaction" )

MethodLogger

Logs method entries and results via LogBox. Self-binding: any class, any method.

mapAspect( "MethodLogger" ).to( "coldbox.system.aop.aspects.MethodLogger" )

---

Complete Example — Security Aspect

// models/aspects/SecuredAspect.bx
/**
 * @classMatcher any
 * @methodMatcher annotatedWith:secured
 */
class implements="wirebox.system.aop.MethodInterceptor" {

    @inject
    property name="securityService";

    @inject "logbox:logger:{this}"
    property name="log";

    function invokeMethod( required invocation ) {
        var meta     = arguments.invocation.getMethodMetadata()
        var required = meta.secured ?: "authenticated"

        if ( required == "authenticated" && !variables.securityService.isLoggedIn() ) {
            log.warn( "Unauthorized access attempt to #arguments.invocation.getMethod()#" )
            throw( type="SecurityException", message="Authentication required" )
        }

        if ( required != "authenticated" && !variables.securityService.hasPermission( required ) ) {
            log.warn( "Permission denied [#required#] on #arguments.invocation.getMethod()#" )
            throw( type="SecurityException", message="Permission denied: #required#" )
        }

        return arguments.invocation.proceed()
    }
}

// config/WireBox.bx
class extends="coldbox.system.ioc.config.ColdBoxBinder" {

    function configure() {
        wirebox = {
            listeners : [{ class: "coldbox.system.aop.Mixer" }]
        }

        // Register self-binding aspects
        mapAspect( "SecuredAspect"   ).to( "models.aspects.SecuredAspect" )
        mapAspect( "CFTransaction"   ).to( "coldbox.system.aop.aspects.CFTransaction" )
        mapAspect( "MethodLogger"    ).to( "coldbox.system.aop.aspects.MethodLogger" )
    }
}

// models/OrderService.bx
class singleton {

    @inject
    property name="orderRepository";

    // Requires 'place-orders' permission
    function checkout( required cart ) secured="place-orders" transactional {
        var order = variables.orderRepository.createFromCart( arguments.cart )
        variables.orderRepository.save( order )
        return order
    }

    // Requires only login
    function getHistory() secured {
        return variables.orderRepository.findAll()
    }
}

---

AOP in Standalone WireBox

Same workflow but use wirebox.system.aop.* namespaces:

// Binder listener
wirebox = {
    listeners : [{ class: "wirebox.system.aop.Mixer" }]
}

// Aspect implements
class implements="wirebox.system.aop.MethodInterceptor" { ... }

// Map aspect
mapAspect( "MyAspect" ).to( "model.aspects.MyAspect" )

---

Checklist for Configuring AOP

1. Add the Mixer listener to wirebox.listeners in your binder (standalone: wirebox.system.aop.Mixer; ColdBox: coldbox.system.aop.Mixer)
2. Create your aspect implementing MethodInterceptor — add DI, implement invokeMethod, call proceed()
3. Register the aspect with mapAspect( "Name" ).to( "path.to.Aspect" )
4. Bind the aspect with bindAspect(classes, methods, aspects) — or use @classMatcher / @methodMatcher annotations for auto-binding
5. Annotate target methods if using annotation-based matching (e.g., transactional, secured)

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Anti-Patterns to Avoid

Anti-pattern	Solution
Forgetting to call invocation.proceed()	Always call it unless intentionally blocking the method
Not returning the result of proceed()	return invocation.proceed() — callers depend on the return value
Registering the Mixer but not calling mapAspect()	Both steps are required — Mixer enables AOP; mapAspect registers the aspect
Applying AOP to transient objects with volatile state	Prefer singletons or application-scope objects as aspect targets
Circular dependencies between aspects	Keep aspects focused; avoid injecting objects that themselves have AOP applied
Using classMatchReload=true in production	Only enable in development — it reloads matchers on every request