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To explain how Dozer can be uses within Camel we'll use the following example of a simple Customer Support Service. The initial version of the Service defined a 'Customer' object used with a very flat structure.

Code Block
lang
langjava
titleLegacy Customer Service Classjava


public class Customer {
    private String firstName;
    private String lastName;
    private String street;
    private String zip;

    public Customer() {}

    public Customer(String firstName, String lastName, String zip, String street) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.zip = zip;
        this.street = street;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    ... getters and setters for each field

In the next version it was decided to structure the data better in the model by moving the address data into its own type, with the resultin domain object ending up looking like

Code Block
lang
langjava
titleNext Gen Customer objectjava


public class Customer {
    private String firstName;
    private String lastName;
    private Address address;

    public Customer() {}

    public Customer(String firstName, String lastName, Address address) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.address = address;
    }
    ....


public class Address {
    private String zipCode;
    private String streetName;

    public Address() {}

    public Address(String zipCode, String streetName) {
        this.zipCode = zipCode;
        this.streetName = streetName;
    }

...

Dozer's configuration is extremely flexible and many mapping scenarios are covered here. For our simple example, the configuration looks like the following.

Code Block
mapping.xml
language mapping.xml
langxml
titlemapping.xml

<mappings xmlns="http://dozer.sourceforge.net" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://dozer.sourceforge.net  http://dozer.sourceforge.net/schema/beanmapping.xsd">
  <mapping>
    <class-a>org.apache.camel.converter.dozer.service.Customer</class-a>
    <class-b>org.apache.camel.converter.dozer.model.Customer</class-b>
    <field>
      <a>street</a>
      <b>address.streetName</b>
    </field>
    <field>
      <a>zip</a>
      <b>address.zipCode</b>
    </field>
  </mapping>
</mappings>

...

In Java it can be configured as follows:

Code Block
langjava

DozerBeanMapper mapper = new DozerBeanMapper(Arrays.asList(new String[]{"mapping.xml"}));
new DozerTypeConverterLoader(camelContext, mapper);

Or in Spring

Code Block
langxml


<!-- the registry will be scanned and 'mapper' below will be found and installed -->
<bean id="dozerConverterLoader" class="org.apache.camel.converter.dozer.DozerTypeConverterLoader" />
  
<bean id="mapper" class="org.dozer.DozerBeanMapper">
  <property name="mappingFiles">
    <list>
      <value>mapping.xml</value>
    </list>
  </property>
</bean>

...

Available as of Camel 2.12.1

When using Dozer with OSGi Blueprint then its works better by configuring dozer Dozer using the org.apache.camel.converter.dozer.DozerBeanMapperConfiguration instead of org.dozer.DozerBeanMapper, as shown below:

Code Block
xml
xml

<!-- the registry will be scanned and 'mapper' below will be found and installed -->
<bean id="dozerConverterLoader" class="org.apache.camel.converter.dozer.DozerTypeConverterLoader">
  <argument index="0" ref="myCamel"/>
  <argument index="1" ref="mapper"/>
</bean>
  
<bean id="mapper" class="org.apache.camel.converter.dozer.DozerBeanMapperConfiguration">
  <property name="mappingFiles">
    <list>
      <value>mapping.xml</value>
    </list>
  </property>
</bean>
 
<camelContext id="myCamel" xmlns="http://camel.apache.org/schema/blueprint">
  ...
</camelContext>

Now, where necessary, Camel will use Dozer to do conversions; In our case between the new domain and legacy Customer types e.g.

Code Block
langjava

// given the following route
from("direct:legacy-service-in").bean(new CustomerProcessor());

// and a processor

public class CustomerProcessor {

    public Customer processCustomer(org.apache.camel.converter.dozer.model.Customer customer) {
       ...
    }
}

// service objects can be sent to the processor and automagically converted by Camel & Dozer
template.sendBody("direct:legacy-service-in",new org.apache.camel.converter.dozer.service.Customer("Bob", "Roberts", "12345", "1 Main st."));