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45.4. Implementing a Type Converter Directly

Overview

Generally, the recommended way to implement a type converter is to use an annotated class, as described in the previous section, Section 45.3, “Implementing Type Converter Using Annotations”. But if you want to have complete control over the registration of your type converter, you can implement a custom slave type converter and add it directly to the type converter registry, as described here.

Implement the TypeConverter interface

To implement your own type converter class, define a class that implements the TypeConverter interface. For example, the following MyOrderTypeConverter class converts an integer value to a MyOrder object, where the integer value is used to initialize the order ID in the MyOrder object.
import org.apache.camel.TypeConverter

private class MyOrderTypeConverter implements TypeConverter {

    public <T> T convertTo(Class<T> type, Object value) {
        // converter from value to the MyOrder bean
        MyOrder order = new MyOrder();
        order.setId(Integer.parseInt(value.toString()));
        return (T) order;
    }

    public <T> T convertTo(Class<T> type, Exchange exchange, Object value) {
        // this method with the Exchange parameter will be preferd by Camel to invoke
        // this allows you to fetch information from the exchange during convertions
        // such as an encoding parameter or the likes
        return convertTo(type, value);
    }

    public <T> T mandatoryConvertTo(Class<T> type, Object value) {
        return convertTo(type, value);
    }

    public <T> T mandatoryConvertTo(Class<T> type, Exchange exchange, Object value) {
        return convertTo(type, value);
    }
}

Add the type converter to the registry

You can add the custom type converter directly to the type converter registry using code like the following:
// Add the custom type converter to the type converter registry
context.getTypeConverterRegistry().addTypeConverter(MyOrder.class, String.class, new MyOrderTypeConverter());
Where context is the current org.apache.camel.CamelContext instance. The addTypeConverter() method registers the MyOrderTypeConverter class against the specific type conversion, from String.class to MyOrder.class.
You can add custom type converters to your Camel applications without having to use the META-INF file. If you are using Spring or Blueprint, then you can just declare a <bean>. CamelContext discovers the bean automatically and adds the converters.
<bean id="myOrderTypeConverters" class="..."/>
 <camelContext>
   ...
</camelContext>
You can declare multiple <bean>s if you have more classes.