---
title: Expression Languages
description: Consult the expression languages available for use
documentId: ipaas-expression-language
locale: en-US
---

An expression language is a way to define conditions or manipulate messages in a declarative manner.
They are used to evaluate and manipulate data within a message, allowing the creation of more complex and flexible routes.

See how to add an expression language directly through an EIP form in the **Diagram** tab:

![](https://creative-ball-51b3fc85c0.media.strapiapp.com/language_expression_f2cfcbee80.gif)

Here are the expression languages supported by **Sensedia Integrations**:

<Callout type="note" title="NOTE">
The examples show the use of languages in the **Choice** component, but they can be used in any context that supports languages.
</Callout>

* **Constant**: returns a constant value.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            constant:
              expression: 'sensedia'    
          steps:
          - log:
              message: 'When activated'
```

* **ExchangeProperty**: accesses Exchange properties.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            exchangeProperty:
              expression: 'myproperty'    
          steps:
          - log:
              message: 'When activated' 
```

* **Groovy**: uses Groovy scripts to manipulate messages.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            groovy:
              expression: 'Math.random() > 0.5'    
          steps:
          - log:
              message: 'When activated' 
```

* **Header**: accesses message header values.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression: 
            header:
              expression: 'myheader'    
          steps:
          - log:
              message: 'When activated' 
```

* **JQ**: uses the JQ language to query and manipulate JSON.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            jq:
              expression: '.store.book.price < 30'    
          steps:  
          - log:
              message: 'When activated'
```

* **JSONPath**: similar to XPath, but for JSON.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            jsonpath:
              expression: $.model.Details[?(@['Random nonsense'] == 'New today')]    
          steps:
          - log:
              message: 'When activated'
```

* **OGNL**: uses Object-Graph Navigation Language expressions to access data.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            ognl:
              expression: 'request.headers.foo == "bar"'      
          steps:
          - log:
              message: 'When activated'
```

* **Simple**: a simple language for expressions and manipulations.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            simple:
              expression: ${header.id} == 2    
          steps:
          - log:
              message: 'When activated'
```

* **XPath**: used to query and manipulate XML.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            xpath:
              expression: '/person/@id > 30'    
          steps:
          - log:
              message: 'When activated'
```

* **XQuery**: uses XQuery to query and manipulate XML.
```yaml
- from:
    uri: rest:post:/demo
    parameters: {}
    steps:
    - choice:
        otherwise:
          steps:
          - log:
              message: 'Otherwise activated'
        when:
        - expression:
            xquery:
              expression: '//foo/id > 30'    
          steps:
          - log:
              message: 'When activated'
```

<Callout type="note" title="NOTE">
For more details, access [the official Apache Camel documentation](https://camel.apache.org/components/4.8.x/languages/index.html).
</Callout>