Package org.thymeleaf.messageresolver

Interface IMessageResolver

  • All Known Implementing Classes:
    AbstractMessageResolver, StandardMessageResolver
    public interface IMessageResolver

    Common interface for all objects used for the resolution of externalized (internationalized) messages.

    A Template Engine can be set several message resolvers, which will be asked for resolution of externalized messages in the order established by the getOrder() method.

    Note that message resolution will return null if no message is found, in which case callers will have the possibility to choose between asking the resolver to create an absent message representation or not. This is precisely what the useAbsentMessageRepresentation flag does in ITemplateContext.getMessage(Class, String, Object[], boolean).

    An absent message representation looks like ??mymessage_gl_ES?? and is useful to quickly determine when a message is lacking from the application's configuration. Note #{...} message expressions will always ask for an absent message representation, whereas methods in the #messages expression object will do it depending on the specific method being called.

    Implementations of this interface should be thread-safe.

    Since:
    3.0.0
    Author:
    Daniel Fernández

    • Method Detail

      • getName

        String getName()

        Returns the name of the message resolver.

        Returns:
        the name of the message resolver

      • getOrder

        Integer getOrder()

        Return the order in which this message resolver will be executed in the chain when several message resolvers are set for the same Template Engine.

        Returns:
        the order of this resolver in the chain.

      • resolveMessage

        String resolveMessage​(ITemplateContext context,
                      Class<?> origin,
                      String key,
                      Object[] messageParameters)

        Resolve the message, returning the requested message (or null if not found).

        Message resolvers should perform resolution of the key + messageParameters pair based on the context and origin specified. The context will provide information about the template and the (optional) origin about the point in template execution from which the message is being requested (usually an IProcessor or the MessageExpression class).

        Parameters:
        context - the ITemplateContext object being used for template processing. Can be null.
        origin - the origin of the message request, usually a processor or expression class. Can be null.
        key - the message key.
        messageParameters - the (optional) message parameters.
        Returns:
        the resolved message, or null if the message could not be resolved.

      • createAbsentMessageRepresentation

        String createAbsentMessageRepresentation​(ITemplateContext context,
                                         Class<?> origin,
                                         String key,
                                         Object[] messageParameters)

        Create a suitable representation of an absent message (a message that could not be resolved).

        Once the entire chain of configured IMessageResolver objects is asked for a specific message and all of them return null, the engine will call this method on the first resolver in the chain. If the first resolver returns null as a representation, the following resolver will be called, and so on until a resolver returns a non-null result. The empty String will be used if all resolvers return null.

        Parameters:
        context - the ITemplateContext object being used for template processing. Can be null.
        origin - the origin of the message request, usually a processor or expression class. Can be null.
        key - the message key.
        messageParameters - the (optional) message parameters.
        Returns:
        the absent message representation, of null if the resolver cannot create such representation.