docs/user-manual/en/producertemplate.adoc

[[ProducerTemplate-ProducerTemplate]]
=== ProducerTemplate

The ProducerTemplate interface allows you to send message exchanges to
endpoints in a variety of different ways to make it easy to work with
Camel link:endpoint.adoc[Endpoint] instances from Java code.

It can be configured with a default endpoint if you just want to send
lots of messages to the same endpoint; or you can specify an
link:endpoint.adoc[Endpoint] or uri as the first parameter.

The `sendBody()` method allows you to send any object to an endpoint
easily.

[source,java]
----
ProducerTemplate template = exchange.getContext().createProducerTemplate();

// send to default endpoint
template.sendBody("<hello>world!</hello>");

// send to a specific queue
template.sendBody("activemq:MyQueue", "<hello>world!</hello>");

// send with a body and header
template.sendBodyAndHeader("activemq:MyQueue",
   "<hello>world!</hello>",
   "CustomerRating", "Gold");
----

You can also supply an `Exchange` or a `Processor` to customize the exchange.


[[ProducerTemplate-requestmethods]]
==== `request*()` methods

The `send*()` methods use the default Message Exchange Pattern (InOnly,
InOut etc) as the endpoint. If you want to explicitly perform a
request/response (InOut) you can use the `request*()` methods instead of
the `send*()` methods.

E.g. let's invoke an endpoint and get the response:

[source,java]
----
Object response = template.requestBody("<hello/>");

// you can cast the response directly
String ret = template.requestBody("<hello/>", String.class);

// or specify the endpoint directly
String ret = template.requestBody("cxf:bean:HelloWorldService", "<hello/>", String.class);
----


[[ProducerTemplate-Fluentinterface]]
==== Fluent interface

*Available as of Camel 2.18.0*

The FluentProducerTemplate provides a fluent syntax to
ProducerTemplate.

Examples:

*Set headers and body*

[source,java]
----
Integer result = FluentProducerTemplate.on(context)
    .withHeader("key-1", "value-1")
    .withHeader("key-2", "value-2")
    .withBody("Hello")
    .to("direct:inout")
    .request(Integer.class);
----

*Use a processor*

[source,java]
----
Integer result = FluentProducerTemplate.on(context)
    .withProcessor(exchange -> exchange.getIn().setBody("Hello World"))
    .to("direct:exception")
    .request(Integer.class);
----

*Customize template*

[source,java]
----
Object result = FluentProducerTemplate.on(context)
    .withTemplateCustomizer(
        template -> {
            template.setExecutorService(myExecutor);
            template.setMaximumCacheSize(10);
        }
    )
    .withBody("the body")
    .to("direct:start")
    .request();
 
----