Introduction¶

Type-safe messages¶

Simple use-case¶

The following implementation is the minimal effort to use type-safe messages (which are hardcoded in this case).

Simple type-safe message

@MessageBundle
public interface SimpleMessage
{
    @MessageTemplate("Welcome to DeltaSpike")
    String welcomeToDeltaSpike();
}

The following implementation uses the key welcome_to_deltaspike to do a lookup in the default message bundle. The default bundle has the same name as the interface (but .properties instead of .java (/.class) as file extension).

Internationalized type-safe message

@MessageBundle
public interface SimpleMessage
{
    @MessageTemplate("{welcome_to_deltaspike}")
    String welcomeToDeltaSpike();
}

org.apache.deltaspike.example.message.SimpleMessage

->

org/apache/deltaspike/example/message/SimpleMessage.properties
org/apache/deltaspike/example/message/SimpleMessage_en.properties
org/apache/deltaspike/example/message/SimpleMessage_de.properties
...

//content (as usual in message bundle files:
welcome_to_deltaspike=Welcome to DeltaSpike

The following implementation uses the key welcome_to_deltaspike to do a lookup in a custom message bundle known by CustomMessageResolver.

Internationalized type-safe message

@MessageBundle
@MessageContextConfig(messageResolver = CustomMessageResolver.class)
public interface SimpleMessage
{
    @MessageTemplate("{welcome_to_deltaspike}")
    String welcomeToDeltaSpike();
}

@MessageContextConfig allows to provide a custom MessageResolver, MessageInterpolator and LocaleResolver.

The following implementation shows the usage of an internationalized simple type-safe message.

Internationalized type-safe message with parameter/s

@MessageBundle
@MessageContextConfig(messageInterpolator = CustomMessageInterpolator.class)
public interface SimpleMessage
{
    //in the message bundle: welcome_to=Welcome to %s

    @MessageTemplate("{welcome_to}")
    String welcomeTo(String name);
}

//...
public class MyBean
{
    @Inject
    private SimpleMessage messages;

    public String welcomeToDeltaSpike
    {
        return this.messages.welcomeTo("DeltaSpike");
    }
}

Dynamic Message Builder¶

Creating message instances¶

The following implementation creates an instance of Message for the key hello. The final text will be resolved and interpolated lazily. Later on it might be supported to provide a different MessageContext via #toString(MessageContext) like it is in MyFaces CODI right now.

[TODO]

Customizing the message context¶

MessageResolver¶

A message-resolver is responsible for creating the message-text based on the message-descriptor (key or inline-text), the current locale (and in some cases the message-payload). (The supported format e.g. if it's required to escape a key, if inline-text is supported,... depends on the concrete implementation.) In case of a message-key, the message-resolver has to transform it to the message-text by looking it up in a message source like a resource-bundle.

Configuration of a message-resolver

[TODO]

The result of a MessageResolver is the message-text. The text might contain placeholders which are processed by a MessageInterpolator

MessageInterpolator¶

A MessageInterpolator replaces the placeholders in a message-text with the arguments of the message.

Configuration of a message-interpolator

[TODO]

LocaleResolver¶

A locale resolver provides the current locale. The locale is e.g. used to by a MessageResolver to choose the correct language for the message-text.

Configuration of a locale-resolver

[TODO]