== Using Interface Types and Abstract Classes ==

The API is defined the same way as in the [wiki:ExampleUsingOwnConceteTypes preceeding use case].

{{{
public interface Api
{
    Param returnParam();
    
    void passAsParameter( Param p );
}

public class Impl implements Api
{
    public Param returnParam() { return createParam( ... ); }
    
    void passAsParameter( Param p ) { doSomethingWith( p ); }
}
}}}

Since Param is an interface, the runtime system cannot create instances of this type without further information.
We use the concrete attribute of the @!XmlRpc annotation to tell the Delight runtime-system what concrete type to use to create instances of type Param.[[BR]]

In this case we use the concete class ''!ParamImpl'' to create instances of type Param (note that ''!ParamImpl'' has to be a Convertable and also has to implement ''Param''):
{{{
@XmlRpc( type=Type.STRING, 
         concrete=ParamImpl.class )
public interface Param
{
    public String printContent() { ... }
}

public class ParamImpl implements Param, 
                                    Convertable<String>
{
    public ParamImpl( String xmlRpcRepresentation ) { processXmlRpc( xmlRpcRepresentation ); }

    public String toXmlRpc() { return( createXmlRpcRep() ); }
}
}}}

=== Client side ===

The client can be created and used without further actions to take. No factories to register. No configuration files to load. Just like a lokal call to the API.
{{{
Api remote_api = XmlRpc.createClient( Api.class, "handlerId", host, port );

Param p = remote_api.returnParam();
System.out.println( p.printContent() );

Param asParam = new ParamImpl(...);
remote_api.passAsParameter( asParam );

...
}}}

== Using !XmlRpcBeans in you API ==

What are !XmlRpcBeans??

Sometimes parameter conversion is a straight-forward task which can be handed over to the XML-RPC runtime system.
When a java class fulfills certain conditions (roughly, being a java bean with compatible types) it can be turned into a !XmlRpcBean
by annotating it with the @!XmlRpcBean annotation. It then can be used in every XML-RPC call without restriction.[[BR]]

A !XmlRpcBean must have

  - a public constructor taking no arguments

  - like a java bean: for each property which is supposed to be transported over XML-RPC there has to exist a public getter and setter method

  - each property type has to be a XML-RPC compliant type, that is it has to have one of the follwoing properties:
    - it is a standard XML-RPC type
    - it is annotated with a @!XmlRpc annotation and defines proper conversion methods
    - a conversion mapping for that type is put at the !XmlRpcBean (which then acts as an API itself)
    - it is an !XmlRpcBean (that is, !XmlRpcBeans can be nested)
    - it is a Collection or Map containing a type which is XML-RPC compliant and is annotated with the @Contains annotation


Technically, an !XmlRpcBean is converted into a XML-RPC STRUCT. The field names of the tranfered map are the property names derived from the bean class.


Lets look at an example !XmlRpcBean (note that this bean also defines a converter mapping for type ''URL''):
{{{
@XmlRpcBean
@ConverterMappings( @Mapping(type=URL.class,converter=URLConverter.class) )
public class CoffeeBean
{
    public URL getOrigin()
    {
        return mOrigin;
    }
    public void setOrigin( URL origin )
    {
        mOrigin = origin;
    }
    public String getType()
    {
        return mType;
    }
    public void setType( String type )
    {
        mType = type;
    }
    
    public String toString()
    {
        return( "CoffeeBean(" + getType() + ") comming from '" + getOrigin() + "'" );
    }
    private String mType;
    private URL mOrigin;
}
}}}

== Client side ==

Again, the client has no restrictions using the bean class:
{{{
public interface Api
{
    @Contains(CoffeeBean.class)
    Collection<CoffeeBean> getAllBeans();
}

----

Api remote_api = XmlRpc.createClient( Api.class, "handlerId", host, port );

Collection<CoffeeBean> beans = remote_api.getAllBeans();

for( CoffeeBeans b: beans )
{
    System.out.println( "Bean of type " + b.getType() + " comes from " + b.getOrigin() );
}
...
}}}

See also [http://delight.opendfki.de/wiki/ExampleUsingOwnConceteTypes#UsingowntypesinCollectionsandMaps How to use own types in Collections an Maps].

Examples in source code: [http://delight.opendfki.de/repos/trunk/XmlRpcDelight/src/examples/de/dfki/util/xmlrpc/examples/interfaces/]