Package org.apache.tapestry5.commons.util

Class StrategyRegistry<A>

  • Type Parameters:
    A - the type of the strategy adapter
    public final class StrategyRegistry<A>
extends java.lang.Object
    A key component in implementing the "Gang of Four" Strategy pattern. A StrategyRegistry will match up a given input type with a registered strategy for that type.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void clearCache()  
      A get​(java.lang.Class type)
      Searches for an adapter corresponding to the given input type.
      java.lang.Class<A> getAdapterType()  
      A getByInstance​(java.lang.Object value)
      Gets an adapter for an object.
      java.util.Collection<java.lang.Class> getTypes()
      Returns the registered types for which adapters are available.
      static <A> StrategyRegistry<A> newInstance​(java.lang.Class<A> adapterType, java.util.Map<java.lang.Class,​A> registrations)
      Creates a strategy registry for the given adapter type.
      static <A> StrategyRegistry<A> newInstance​(java.lang.Class<A> adapterType, java.util.Map<java.lang.Class,​A> registrations, boolean allowNonMatch)
      Creates a strategy registry for the given adapter type.
      java.lang.String toString()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Method Detail

      • newInstance

        public static <A> StrategyRegistry<A> newInstance​(java.lang.Class<A> adapterType,
                                                  java.util.Map<java.lang.Class,​A> registrations)
        Creates a strategy registry for the given adapter type. The registry will be configured to require matches.
        Parameters:
        adapterType - the type of adapter retrieved from the registry
        registrations - map of registrations (the contents of the map are copied)

      • newInstance

        public static <A> StrategyRegistry<A> newInstance​(java.lang.Class<A> adapterType,
                                                  java.util.Map<java.lang.Class,​A> registrations,
                                                  boolean allowNonMatch)
        Creates a strategy registry for the given adapter type.
        Parameters:
        adapterType - the type of adapter retrieved from the registry
        registrations - map of registrations (the contents of the map are copied)
        allowNonMatch - if true, then the registry supports non-matches when retrieving an adapter

      • getByInstance

        public A getByInstance​(java.lang.Object value)
        Gets an adapter for an object. Searches based on the value's class, unless the value is null, in which case, a search on class void is used.
        Parameters:
        value - for which an adapter is needed
        Returns:
        the adapter for the value or null if not found (and allowNonMatch is true)
        Throws:
        java.lang.IllegalArgumentException - if no matching adapter may be found and allowNonMatch is false

      • get

        public A get​(java.lang.Class type)
        Searches for an adapter corresponding to the given input type.
        Parameters:
        type - the type to search
        Returns:
        the adapter for the type or null if not found (and allowNonMatch is true)
        Throws:
        java.lang.IllegalArgumentException - if no matching adapter may be found and allowNonMatch is false

      • getTypes

        public java.util.Collection<java.lang.Class> getTypes()
        Returns the registered types for which adapters are available.

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object