The xslt: component allows you to process a message using an XSLT template. This can be ideal when using Templating to generate respopnses for requests.
xslt:templateName[?options]
Where templateName is the classpath-local URI of the template to invoke; or the complete URL of the remote template. Refer to the Spring Documentation for more detail of the URI syntax
You can append query options to the URI in the following format,
?option=value&option=value&...
Here are some example URIs:
URI | Description |
---|---|
xslt:com/acme/mytransform.xs
| Refers to the file, com/acme/mytransform.xsl , on the
classpath. |
xslt:file:///foo/bar.xs
| Refers to the file, /foo/bar.xsl . |
xslt:http://acme.com/cheese/foo.xsl
| Refers to the remote HTTP resource. |
Table 75 lists the XSLT uri options:
Table 75. URI options
Name | Default Value | Description |
---|---|---|
converter | null | Option to override default XmlConverter. Will lookup for the converter in the Registry. The provided converted must be of type org.apache.camel.converter.jaxp.XmlConverter. |
transformerFactory | null | New added in Apache Camel 1.6 Option
to override default TransformerFactory. Will lookup for the transformerFactory
in the Registry. The provided transformer factory must be of type
javax.xml.transform.TransformerFactory . |
transformerFactoryClass | null | New added in Apache Camel 1.6 Option
to override default TransformerFactory. Will create a
TransformerFactoryClass instance and set it to the
converter. |
uriResolver | null | Apache Camel 2.3: Allows you to use
a custom javax.xml.transformation.URIResolver . Camel
will by default use its own implementation
org.apache.camel.builder.xml.XsltUriResolver
which is capable of loading from classpath. |
resultHandlerFactory | null | Apache Camel 2.3: Allows you to use
a custom
org.apache.camel.builder.xml.ResultHandlerFactory
which is capable of using custom
org.apache.camel.builder.xml.ResultHandler
types. |
failOnNullBody | true | Apache Camel 2.3: Whether or not to throw an exception if the input body is null. |
output | string | Apache Camel 2.3: Option to specify
which output type to use. Possible values are: string, bytes,
DOM, file . The first three options are all in memory
based, where as file is streamed directly to a
java.io.File . For file you
must specify the filename in the IN
header with the key Exchange.XSLT_FILE_NAME which is
also CamelXsltFileName . Also any paths leading to the
filename must be created beforehand, otherwise an exception is thrown at
runtime. |
contentCache | true | Apache Camel 2.6: Cache for the
resource content (the stylesheet file) when it is loaded. If set to
false Camel will reloader the stylesheet file on
each message processing. This is good for development. |
For example you could use something like
from("activemq:My.Queue"). to("xslt:com/acme/mytransform.xsl");
To use an XSLT template to forumulate a response for a message for InOut message
exchanges (where there is a JMSReplyTo
header).
If you want to use InOnly and consume the message and send it to another destination you could use the following route:
from("activemq:My.Queue"). to("xslt:com/acme/mytransform.xsl"). to("activemq:Another.Queue");
By default, all headers are added as parameters which are available in the XSLT. To do this you will need to declare the parameter so it is then useable.
<setHeader headerName="myParam"><constant>42</constant></setHeader> <to uri="xslt:MyTransform.xsl"/>
And the XSLT just needs to declare it at the top level for it to be available:
<xsl: ...... > <xsl:param name="myParam"/> <xsl:template ...>
To use the above examples in XML you would use something like
<camelContext xmlns="http://activemq.apache.org/camel/schema/spring"> <route> <from uri="activemq:My.Queue"/> <to uri="xslt:org/apache/camel/spring/processor/example.xsl"/> <to uri="activemq:Another.Queue"/> </route> </camelContext>
There is a test case along with its Spring XML if you want a concrete example.
Apache Camel 1.6.2/2.2 or older If you use
xsl:include in your XSL files then in Camel 2.2 or older it uses the default
javax.xml.transform.URIResolver
which means it can only lookup
files from file system, and its does that relative from the JVM starting folder.
For example this include:
<xsl:include href="staff_template.xsl"/>
Will lookup the staff_tempkalte.xsl
file from the starting folder
where the application was started.
Apache Camel 1.6.3/2.3 or newer Now Camel provides
its own implementation of URIResolver
which allows Camel to load
included files from the classpath and more intelligent than before.
For example this include:
<xsl:include href="staff_template.xsl"/>
Will now be located relative from the starting endpoint, which for example could be:
.to("xslt:org/apache/camel/component/xslt/staff_include_relative.xsl")
Which means Camel will locate the file in the classpath as
org/apache/camel/component/xslt/staff_template.xsl
. This allows
you to use xsl include and have xsl files located in the same folder such as we do in
the example org/apache/camel/component/xslt
.
You can use the following two prefixes classpath:
or
file:
to instruct Camel to look either in classpath or file
system. If you omit the prefix then Camel uses the prefix from the endpoint
configuration. If that neither has one, then classpath is assumed.
You can also refer back in the paths such as
<xsl:include href="../staff_other_template.xsl"/>
Which then will resolve the xsl file under
org/apache/camel/component
.