---
title: 7. Annotator
---

Annotator helps highlight and annotate any code based on specific rules.

### 7.1. Define an annotator

In this tutorial we will annotate usages of our properties within Java code.
Let's consider a literal which starts with *"simple:"* as a usage of our property.

```
{% include /code_samples/simple_language_plugin/src/com/simpleplugin/SimpleAnnotator.java %}
```

### 7.2. Register the annotator

```xml
<annotator language="JAVA" implementationClass="com.simpleplugin.SimpleAnnotator"/>
```

### 7.3. Run the project

Let's define the following Java file and check if the IDE resolves a property.

```java
public class Test {
    public static void main(String[] args) {
        System.out.println("simple:website");
    }
}
```

![Annotator](img/annotator.png)

If we type an undefined property name, it will annotate the code with a error.

![Unresolved property](img/unresolved_property.png)

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