Package com.yahoo.documentapi.messagebus.systemstate.rule

Class NodeState

  • public class NodeState
extends Object
    Author:
    Simon Thoresen Hult

    • Field Detail

      • NODE_PARENT

        public static final String NODE_PARENT
        A location string that expresses the use of the PARENT node.
        See Also:
        Constant Field Values

      • NODE_CURRENT

        public static final String NODE_CURRENT
        A location string that expresses the use of THIS node.
        See Also:
        Constant Field Values

    • Constructor Detail

      • NodeState

        public NodeState()
        Creates a node state that no internal content.

      • NodeState

        public NodeState​(List<Argument> args)
        Creates a node state based on a list of argument objects. These arguments are iterated and added to this node's internal state map.
        Parameters:
        args - The arguments to use as state.

    • Method Detail

      • addChild

        public NodeState addChild​(String key,
                          NodeState child)
        Adds a child to this node at the given location. The key can be a location string, in which case the necessary intermediate node states are created.
        Parameters:
        key - The location at which to add the child.
        child - The child node to add.
        Returns:
        This, to allow chaining.

      • getChild

        public NodeState getChild​(String key)
        Returns the child at the given location relative to this.
        Parameters:
        key - The location of the child to return.
        Returns:
        The child object, null if not found.

      • getChild

        public NodeState getChild​(String key,
                          boolean force)
        Returns the child at the given location relative to this. This method can be forced to return a child node even if it does not exist, by adding all intermediate nodes and the target node itself.
        Parameters:
        key - The location of the child to return.
        force - Whether or not to force a return value by creating missing nodes.
        Returns:
        The child object, null if not found.

      • getChildren

        public Map<String,​NodeState> getChildren()
        Returns the map of child nodes for iteration.
        Returns:
        The internal child map.

      • removeChild

        public NodeState removeChild​(String key)
        Removes the named child node from this node, and attempts to compact the system state from this node upwards by removing empty nodes.
        Parameters:
        key - The child to remove.
        Returns:
        The result of invoking compact() after the remove.

      • getState

        public String getState​(String key)
        Retrieves some arbitrary state information for a given key. The key can be a location string, in which case the necessary intermediate nodes are traversed. If the key is not found, this method returns null.
        Parameters:
        key - The name of the state information to return.
        Returns:
        The value of the state key.

      • setState

        public NodeState setState​(String key,
                          String value)
        Sets some arbitrary state data in this node. The key can be a location string, in which case the necessary intermediate nodes are traversed and even created if missing.
        Parameters:
        key - The key to set.
        value - The value to assign to the key.
        Returns:
        This, to allow chaining.

      • removeState

        public NodeState removeState​(String key)
        Removes the named (key, value) state pair from this node, and attempts to compact the system state from this node upwards by removing empty nodes.
        Parameters:
        key - The state variable to clear.
        Returns:
        The result of invoking compact() after the remove.

      • copy

        public NodeState copy​(NodeState node)
        Copies the state content of another node state object into this.
        Parameters:
        node - The node state to copy into this.
        Returns:
        This, to allow chaining.

      • clear

        public NodeState clear()
        Clears both the internal state and child list, then compacts the tree from this node upwards.
        Returns:
        The result of invoking compact() after the remove.

      • setParent

        public NodeState setParent​(NodeState parent,
                           String id)
        Sets the parent of this node.
        Parameters:
        parent - The parent node.
        id - The identifier of this node as seen in the parent.
        Returns:
        This, to allow chaining.