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9.5. Sort

Sort

The sort pattern is used to sort the contents of a message body, assuming that the message body contains a list of items that can be sorted.
By default, the contents of the message are sorted using a default comparator that handles numeric values or strings. You can provide your own comparator and you can specify an expression that returns the list to be sorted (the expression must be convertible to java.util.List).

Java DSL example

The following example generates the list of items to sort by tokenizing on the line break character:
from("file://inbox").sort(body().tokenize("\n")).to("bean:MyServiceBean.processLine");
You can pass in your own comparator as the second argument to sort():
from("file://inbox").sort(body().tokenize("\n"), new MyReverseComparator()).to("bean:MyServiceBean.processLine");

XML configuration example

You can configure the same routes in Spring XML.
The following example generates the list of items to sort by tokenizing on the line break character:
<route>
  <from uri="file://inbox"/>
  <sort>
    <simple>body</simple>
  </sort>
  <beanRef ref="myServiceBean" method="processLine"/>
</route>
And to use a custom comparator, you can reference it as a Spring bean:
<route>
  <from uri="file://inbox"/>
  <sort comparatorRef="myReverseComparator">
    <simple>body</simple>
  </sort>
  <beanRef ref="MyServiceBean" method="processLine"/>
</route>

<bean id="myReverseComparator" class="com.mycompany.MyReverseComparator"/>
Besides <simple>, you can supply an expression using any language you like, so long as it returns a list.

Options

The sort DSL command supports the following options:
Name Default Value Description
comparatorRef Refers to a custom java.util.Comparator to use for sorting the message body. Camel will by default use a comparator which does a A..Z sorting.