# Injection DSL

The injection DSL is a domain specific language that denotes what to inject in the current placeholder: property, argument, or method via the inject annotation. This injection DSL not only can it be used via annotations but also via our mapping DSL whenever a `dsl` argument can be used. This DSL is constructed by joining words separated by a `:` colon. The first part of this string is what we will denote as the injection **DSL Namespace**.

```
inject="{namespace}:extra:extra:extra"
```

## Property Annotation

Every property can be annotated with our injection annotations:

* `inject` : The injection DSL
* `scope` : The visibility scope to inject the dependency into. By default it injects into `variables` scope

{% tabs %}
{% tab title="BoxLang" %}

```java
property name="service" inject="id:MyService";

property name="TYPES" inject="id:CustomTypes" scope="this";

property name="roles" inject="id:RoleService:getRoles" scope="instance";
```

{% endtab %}

{% tab title="CFML" %}

```javascript
property name="service" inject="id:MyService";

property name="TYPES" inject="id:CustomTypes" scope="this";

property name="roles" inject="id:RoleService:getRoles" scope="instance";
```

{% endtab %}
{% endtabs %}

## Constructor Argument Annotation

You can also annotate constructor arguments with the inject annotation:

{% tabs %}
{% tab title="BoxLang" %}

```java
/**
 * @myService.inject UserService
 * @cache.inject    cachebox:default
 */
function init( required myService, required cache ){
}
```

{% endtab %}

{% tab title="CFML" %}

```javascript
/**
 * @myService.inject UserService
 * @cache.inject     cachebox:default
 */
function init( required myService, required cache ){
}
```

{% endtab %}
{% endtabs %}

## Setter Method Annotation

You can also annotate setter methods with the inject annotation to provide injections:

{% tabs %}
{% tab title="BoxLang" %}

```java
function setService( required service ) inject="UserService" {
    variables.service = arguments.service
}
```

{% endtab %}

{% tab title="CFML" %}

```javascript
function setService( required service ) inject="UserService" {
    variables.service = arguments.service;
}
```

{% endtab %}
{% endtabs %}

WireBox offers a wide gamut of annotation namespaces you can use in your BoxLang and CFML applications and ColdBox applications. However, we took it a step further and allowed you to create your own custom DSL namespaces making your annotations come alive!


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://wirebox.ortusbooks.com/usage/injection-dsl.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.