Package org.apache.tapestry5.internal.util

Class NamedSet<T>

  • Type Parameters:
    T - the type of value stored
    public class NamedSet<T>
extends LockSupport
    Simple, thread-safe associative array that relates a name to a value. Names are case-insensitive. This is optimized to use less memory (than a CaseInsensitiveMap (it uses a singly-liked list), though the cost of a lookup is more expensive. However, this is a good match against many of the structures inside a page instance, where most lookups occur only during page constructions, and the number of values is often small. Each NameSet has its own ReadWriteLock.

    • Constructor Summary

      Constructors 
      Constructor Description
      NamedSet()  

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static <T> NamedSet<T> create()
      Convenience method for creating a new, empty set.
      void eachValue​(Worker<T> worker)
      Iterates over the values, passing each in turn to the supplied worker.
      T get​(java.lang.String name)
      Gets the value for the provided name.
      static <T> T get​(NamedSet<T> set, java.lang.String name)
      Convenience method for getting a value from a set that may be null.
      java.util.Set<java.lang.String> getNames()
      Returns a set of the names of all stored values.
      static java.util.Set<java.lang.String> getNames​(NamedSet<?> set)
      Gets the names in the set, returning an empty set if the NamedSet is null.
      java.util.Set<T> getValues()
      Returns a set of all the values in the set.
      static <T> java.util.Set<T> getValues​(NamedSet<T> set)
      Returns the values in the set, returning an empty set if the NamedSet is null.
      void put​(java.lang.String name, T newValue)
      Stores a new value into the set, replacing any previous value with the same name.
      boolean putIfNew​(java.lang.String name, T newValue)
      Puts a new value, but only if it does not already exist.

      • Methods inherited from class java.lang.Object

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

    • Method Detail

      • getNames

        public java.util.Set<java.lang.String> getNames()
        Returns a set of the names of all stored values.

      • getValues

        public java.util.Set<T> getValues()
        Returns a set of all the values in the set.

      • get

        public T get​(java.lang.String name)
        Gets the value for the provided name.
        Parameters:
        name - used to locate the value
        Returns:
        the value, or null if not found

      • put

        public void put​(java.lang.String name,
                T newValue)
        Stores a new value into the set, replacing any previous value with the same name. Name comparisons are case insensitive.
        Parameters:
        name - to store the value. May not be blank.
        newValue - non-null value to store

      • eachValue

        public void eachValue​(Worker<T> worker)
        Iterates over the values, passing each in turn to the supplied worker.
        Parameters:
        worker - performs an operation on, or using, the value

      • putIfNew

        public boolean putIfNew​(java.lang.String name,
                        T newValue)
        Puts a new value, but only if it does not already exist.
        Parameters:
        name - name to store (comparisons are case insensitive) may not be blank
        newValue - non-null value to store
        Returns:
        true if value stored, false if name already exists

      • create

        public static <T> NamedSet<T> create()
        Convenience method for creating a new, empty set.

      • get

        public static <T> T get​(NamedSet<T> set,
                        java.lang.String name)
        Convenience method for getting a value from a set that may be null.
        Type Parameters:
        T -
        Parameters:
        set - set to search, may be null
        name - name to lookup
        Returns:
        value from set, or null if not found, or if set is null

      • getNames

        public static java.util.Set<java.lang.String> getNames​(NamedSet<?> set)
        Gets the names in the set, returning an empty set if the NamedSet is null.

      • getValues

        public static <T> java.util.Set<T> getValues​(NamedSet<T> set)
        Returns the values in the set, returning an empty set if the NamedSet is null.