Interface MetaDataLocator

All Known Implementing Classes:
MetaDataLocatorImpl

Used to lookup meta data concerning a particular component. The primary source of meta data is the meta data defined for the component, accessed via ComponentModel.getMeta(String). This includes meta data defined by base classes. When meta-data for a particular component can not be found, a search works up the containment hierarchy (to the component's container, and the container's container, and so on). If that proves unfruitful, a system of defaults is provided by configuration and matched against the containing page's logical name. Finally, if no metadata is available, then SymbolSource.valueForSymbol(String) is used to obtain a value. Generally speaking, if you are going to use this service to look up meta data, your should also make a contribution to the FactoryDefaults service; otherwise, you risk a runtime exception if a meta-data key can not be resolved.
  • Method Summary

    Modifier and Type
    Method
    Description
    <T> T
    findMeta(String key, String pageName, Class<T> expectedType)
    Searches for the value for the corresponding key for a particular page name (the page will not be loaded).
    <T> T
    findMeta(String key, ComponentResources resources, Class<T> expectedType)
    Searches for the value for the corresponding key.
  • Method Details

    • findMeta

      <T> T findMeta(String key, ComponentResources resources, Class<T> expectedType)
      Searches for the value for the corresponding key. The value, if located, will have symbols expanded, and will be type coerced to the desired type.
      Parameters:
      key - the key used to locate the meta data (case insensitive)
      resources - the resources of the initial component used in the search
      Returns:
      the value if found (in the component, the component's container, etc. or via a folder default)
      Throws:
      RuntimeException - if the value for the key is not present as meta data of the component, as an override, or as a symbol
    • findMeta

      <T> T findMeta(String key, String pageName, Class<T> expectedType)
      Searches for the value for the corresponding key for a particular page name (the page will not be loaded). The value, if located, will have symbols expanded, and will be type coerced to the desired type.
      Parameters:
      key - the key used to locate the meta data (case insensitive)
      pageName - the name of the page to search
      Returns:
      the value if found
      Throws:
      RuntimeException - if the value for the key is not present as meta data of the page, as an override, or as a symbol