XQuery

Overview

XQuery was devised primarily as a query language for data stored in XML form. Its main role is to get information out of XML databases. XQuery support is supplied by the camel-saxon module.

Adding the Saxon module

To use XQuery in your routes you need to add a dependency on camel-saxon to your project as shown in Example 22, “Adding the camel-script dependency”.

Example 22. Adding the camel-script dependency

<!-- Maven POM File -->
...
<dependencies>
  ...
  <dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-saxon</artifactId>
    <version>${camel-version}</version>
  </dependency>
  ...
</dependencies>

Variables

Table 15, “XQuery variables” lists the variables that are accessible when using XQuery.

Table 15. XQuery variables

Variable	Type	Description
`exchange`	`Exchange`	The current Exchange
`in.body`	`Object`	The body of the IN message
`out.body`	`Object`	The body of the OUT message
`in.headers.key`	`Object`	The IN message header whose key is `key`
`out.headers.key`	`Object`	The OUT message header whose key is `key`
`key`	`Object`	The Exchange property whose key is `key`

Example

Example 23, “Route using XQuery” shows a route that uses XQuery.

Example 23. Route using XQuery

<camelContext>
  <route>
    <from uri="activemq:MyQueue"/>
    <filter>
      <language langauge="xquery">/foo:person[@name='James']</language>
      <to uri="mqseries:SomeOtherQueue"/>
    </filter>
  </route>
</camelContext>