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The Simple language can be used for the predicate test above in the Message Filter pattern, where we test if the in message has a foo header (a header with the key foo exists). If the expression evaluates to true then the message is routed to the mock:foo endpoint, otherwise its lost in the deep blue sea .The same example in Java DSLin the deep blue sea .

The same example in Java DSL:

    from("seda:orders")
        .filter().simple("in.header.foo").to("seda:fooOrders");

You can also use the simple language for simple text concatenations such as:

    from("sedadirect:ordershello")
        .filter.transform().simple("Hello ${in.header.foouser} how are you?").to("sedamock:fooOrdersreply");

Notice that we must use ${ } placeholders in the expression now to let Camel be able to parse it correctly.

And this sample uses the date command to output current date.You can also use the simple language for simple text concatenations such as:

   from("direct:hello").transform().simple("HelloThe today is ${in.header.user} how are you?date:now:yyyyMMdd} and its a great day.").to("mock:reply");

Notice that we must use ${ } placeholders in the expression now to let Camel be able to parse it correctly.

And this sample uses the date command to output current date.And in the sample below we invoke the bean language to invoke a method on a bean to be included in the returned string:

   from("direct:helloorder").transform().simple("The today isOrderId: ${datebean:now:yyyyMMdd} and its a great day.orderIdGenerator}").to("mock:reply");
);

Where orderIdGenerator is the id of the bean registered in the Registry. If using Spring then its the Spring bean id.

If we want to declare which method to invoke on the order id generator bean we must prepend .method name such as below where we invoke the generateId method.And in the sample below we invoke the bean language to invoke a method on a bean to be included in the returned string:

   from("direct:order").transform().simple("OrderId: ${bean:orderIdGenerator.generateId}").to("mock:reply");

Where orderIdGenerator is the id of the bean registered in the Registry. If using Spring then its the Spring bean id.

If we want to declare which method to invoke on the order id generator bean we must prepend .method name such as below where we invoke the generateId method.And in Camel 2.0 we can use the ?method=methodname option that we are familiar with the Bean component itself:

   from("direct:order").transform().simple("OrderId: ${bean:orderIdGenerator.?method=generateId}").to("mock:reply");

And in from Camel 2.0 we can use the ?method=methodname option that we are familiar with the Bean component itself3 onwards you can also convert the body to a given type, for example to ensure its a String you can do:

  <transform>
   from("direct:order").transform().simple("OrderId: ${bean:orderIdGenerator?method=generateId}").to("mock:reply");
 <simple>Hello ${bodyAs(String)} how are you?</simple>
  </transform>

There is a few types which have a shorthand notation, hence why we can use String instead of java.lang.String. These are: byte[], String, Integer, Long. All other types must use their FQN name, e.g. org.w3c.dom.Document.

Its also possible to lookup a value from a header Map in Camel 2.3 onwardsAnd from Camel 2.3 onwards you can also convert the body to a given type, for example to ensure its a String you can do:

  <transform>
    <simple>Hello<simple>The gold value is ${bodyAs(String)} how are you?header.type[gold]}</simple>
  </transform>

There is a few types which have a shorthand notation, hence why we can use String instead of java.lang.String. These are: byte[], String, Integer, Long. All other types must use their FQN name, e.g. org.w3c.dom.DocumentIn the code above we lookup the header with name type and regard it as a java.util.Map and we then lookup with the key gold and return the value.
If the header is not convertible to Map an exception is thrown. If the header with name type does not exists null is returned.

Dependencies

The Bean language is part of camel-core.