Package org.terracotta.context

Class ContextManager

  • Direct Known Subclasses:
    StatisticsManager
    public class ContextManager
extends java.lang.Object
    A ContextManager instances allows for rooting, querying and access to select portions of the global context graph.

    • Constructor Detail

      • ContextManager

        public ContextManager()

    • Method Detail

      • associate

        public static ContextManager.Association associate​(java.lang.Object object)
        Create an Association instance for the supplied object.
        Parameters:
        object - the object to be associated
        Returns:
        an association instance

      • dissociate

        public static ContextManager.Dissociation dissociate​(java.lang.Object object)
        Create a Dissociation instance for the supplied object.
        Parameters:
        object - the object to be dissociated
        Returns:
        a dissociation instance

      • nodeFor

        public static TreeNode nodeFor​(java.lang.Object object)
        Return the TreeNode associated with this object.

        Returns null if the supplied object has no associated context node.

        Parameters:
        object - object to lookup node for
        Returns:
        TreeNode associated with this object

      • registerContextCreationListener

        public static void registerContextCreationListener​(ContextCreationListener listener)

      • deregisterContextCreationListener

        public static void deregisterContextCreationListener​(ContextCreationListener listener)

      • associate

        private static void associate​(java.lang.Object child,
                              java.lang.Object parent)

      • dissociate

        private static void dissociate​(java.lang.Object child,
                               java.lang.Object parent)

      • getTreeNode

        private static MutableTreeNode getTreeNode​(java.lang.Object object)

      • getOrCreateTreeNode

        private static MutableTreeNode getOrCreateTreeNode​(java.lang.Object object)

      • discoverAssociations

        private static void discoverAssociations​(java.lang.Object origin)

      • contextCreated

        private static void contextCreated​(java.lang.Object object)

      • root

        public void root​(java.lang.Object object)
        Root the given object's context node in this ContextManager instance.
        Parameters:
        object - object whose context will be rooted

      • uproot

        public void uproot​(java.lang.Object object)
        Remove the given object's context node from this ContextManager root set.
        Parameters:
        object - object whose context will be uprooted

      • query

        public java.util.Set<TreeNode> query​(Query query)
        Run the supplied Query against this ContextManager's root context.

        The initial node in the queries traversal will be the node whose children form the root set of this ContextManager. That is, the following code will select the root set of this instance.

         public static Set<TreeNode> roots(ContextManager manager) {
   return manager.query(QueryBuilder.queryBuilder().children().build());
 }
        Parameters:
        query - the query to execute
        Returns:
        the set of nodes selected by the query

      • queryForSingleton

        public TreeNode queryForSingleton​(Query query)
                           throws java.lang.IllegalStateException
        Return the unique node selected by running this query against this ContextManager's root context.

        If this query does not return a single unique result then an IllegalStateException will be thrown. More details on the query execution context can be found in query(Query).

        Parameters:
        query - the query to execute
        Returns:
        the node selected by the query
        Throws:
        java.lang.IllegalStateException - if the query does not select a unique node
        See Also:
        query(Query), QueryBuilder.ensureUnique()

      • registerContextListener

        public void registerContextListener​(ContextListener listener)
        Registers a listener for additions and removals to this ContextManager's context graph.
        Parameters:
        listener - listener to be registered

      • deregisterContextListener

        public void deregisterContextListener​(ContextListener listener)
        Removes a previously registered listener from the listener set.
        Parameters:
        listener - listener to be deregistered