Class TransactionalResourceHelper


  • public abstract class TransactionalResourceHelper
    extends Object
    Helper class that will look up or create transactional resources. This shortcuts some of the "if not existing, then create" code.
    Since:
    3.2
    Author:
    Derek Hulley
    • Constructor Detail

      • TransactionalResourceHelper

        public TransactionalResourceHelper()
    • Method Detail

      • getCount

        public static final int getCount​(Object resourceKey)
        Get the current count value for a named key
        Parameters:
        resourceKey - the key to count against
        Returns:
        the current value for the named key
      • resetCount

        public static final void resetCount​(Object resourceKey)
        Reset the current count value for a named key. After this operation, the effective value will be 0.
        Parameters:
        resourceKey - the key to count against
      • incrementCount

        public static final int incrementCount​(Object resourceKey)
        Increment a count value for named key
        Parameters:
        resourceKey - the key to count against
        Returns:
        the newly-incremented value
      • decrementCount

        public static final int decrementCount​(Object resourceKey,
                                               boolean allowNegative)
        Decrement a count value for a named key
        Parameters:
        resourceKey - the key to count against
        allowNegative - true to allow negative values otherwise zero will be the floor
        Returns:
        the newly-decremented value (negative, if allowed)
      • isResourcePresent

        public static final boolean isResourcePresent​(Object resourceKey)
        Support method to determine if there is already a resource associated with the given key. This method allows quick conditional checking of the key without building a new collection.
        Parameters:
        resourceKey - the key of the resource to check
        Returns:
        true if a resource is already present at the key
      • getMap

        public static final <K,​V> Map<K,​V> getMap​(Object resourceKey)
        Support method to retrieve or create and bind a HashMap to the current transaction.
        Type Parameters:
        K - the map key type
        V - the map value type
        Parameters:
        resourceKey - the key under which the resource will be stored
        Returns:
        Returns an previously-bound Map or else a newly-bound HashMap
      • getSet

        public static final <V> Set<V> getSet​(Object resourceKey)
        Support method to retrieve or create and bind a HashSet to the current transaction.
        Type Parameters:
        V - the set value type
        Parameters:
        resourceKey - the key under which the resource will be stored
        Returns:
        Returns an previously-bound Set or else a newly-bound HashSet
      • getTreeSet

        public static final <V> TreeSet<V> getTreeSet​(Object resourceKey)
        Support method to retrieve or create and bind a TreeSet to the current transaction.
        Type Parameters:
        V - the set value type
        Parameters:
        resourceKey - the key under which the resource will be stored
        Returns:
        Returns an previously-bound TreeSet or else a newly-bound TreeSet
      • getList

        public static final <V> List<V> getList​(Object resourceKey)
        Support method to retrieve or create and bind a ArrayList to the current transaction.
        Type Parameters:
        V - the list value type
        Parameters:
        resourceKey - the key under which the resource will be stored
        Returns:
        Returns an previously-bound List or else a newly-bound ArrayList