Package org.apache.jackrabbit.oak.plugins.memory

Class ModifiedNodeState

java.lang.Object
org.apache.jackrabbit.oak.spi.state.AbstractNodeState
org.apache.jackrabbit.oak.plugins.memory.ModifiedNodeState
All Implemented Interfaces:
NodeState
public class ModifiedNodeState extends AbstractNodeState
Immutable snapshot of a mutable node state.

  • Method Details

    • squeeze

      public static NodeState squeeze(NodeState state)
      "Squeezes" ModifiedNodeState instances into equivalent MemoryNodeStates. Other kinds of states are returned as-is.

    • getBaseState

      @NotNull public @NotNull NodeState getBaseState()

    • builder

      @NotNull public @NotNull NodeBuilder builder()
      Description copied from interface: NodeState
      Returns a builder for constructing a new node state based on this state, i.e. starting with all the properties and child nodes of this state.
      Returns:
      node builder based on this state

    • exists

      public boolean exists()
      Description copied from interface: NodeState
      Checks whether this node exists. See the above discussion about the existence of node states.
      Returns:
      true if this node exists, false if not

    • getPropertyCount

      public long getPropertyCount()
      Description copied from interface: NodeState
      Returns the number of properties of this node.
      Specified by:
      getPropertyCount in interface NodeState
      Overrides:
      getPropertyCount in class AbstractNodeState
      Returns:
      number of properties

    • hasProperty

      public boolean hasProperty(@NotNull @NotNull String name)
      Description copied from interface: NodeState
      Checks whether the named property exists. The implementation is equivalent to getProperty(name) != null, but may be optimized to avoid having to load the property value.
      Specified by:
      hasProperty in interface NodeState
      Overrides:
      hasProperty in class AbstractNodeState
      Parameters:
      name - property name
      Returns:
      true if the named property exists, false otherwise

    • getProperty

      public PropertyState getProperty(@NotNull @NotNull String name)
      Description copied from interface: NodeState
      Returns the named property, or null if no such property exists.
      Specified by:
      getProperty in interface NodeState
      Overrides:
      getProperty in class AbstractNodeState
      Parameters:
      name - name of the property to return
      Returns:
      named property, or null if not found

    • getProperties

      @NotNull public @NotNull Iterable<? extends PropertyState> getProperties()
      Description copied from interface: NodeState
      Returns an iterable of the properties of this node. Multiple iterations are guaranteed to return the properties in the same order, but the specific order used is implementation-dependent and may change across different states of the same node.
      Returns:
      properties in some stable order

    • getChildNodeCount

      public long getChildNodeCount(long max)
      Description copied from interface: NodeState
      Returns the number of iterable child nodes of this node.

      If an implementation knows the exact value, it returns it (even if the value is higher than max). If the implementation does not know the exact value, and the child node count is higher than max, it may return Long.MAX_VALUE. The cost of the operation is at most O(max).

      Specified by:
      getChildNodeCount in interface NodeState
      Overrides:
      getChildNodeCount in class AbstractNodeState
      Parameters:
      max - the maximum number of entries to traverse
      Returns:
      number of iterable child nodes

    • hasChildNode

      public boolean hasChildNode(@NotNull @NotNull String name)
      Description copied from interface: NodeState
      Checks whether the named child node exists. The implementation is equivalent to getChildNode(name).exists(), except that passing an invalid name as argument will result in a false return value instead of an IllegalArgumentException.
      Parameters:
      name - name of the child node
      Returns:
      true if the named child node exists, false otherwise

    • getChildNode

      @NotNull public @NotNull NodeState getChildNode(@NotNull @NotNull String name)
      Description copied from interface: NodeState
      Returns the named, possibly non-existent, child node. Use the NodeState.exists() method on the returned child node to determine whether the node exists or not.
      Parameters:
      name - name of the child node to return
      Returns:
      named child node

    • getChildNodeNames

      public Iterable<String> getChildNodeNames()
      Description copied from interface: NodeState
      Returns the names of all iterable child nodes.
      Specified by:
      getChildNodeNames in interface NodeState
      Overrides:
      getChildNodeNames in class AbstractNodeState
      Returns:
      child node names in some stable order

    • getChildNodeEntries

      @NotNull public @NotNull Iterable<? extends ChildNodeEntry> getChildNodeEntries()
      Description copied from interface: NodeState
      Returns the iterable child node entries of this instance. Multiple iterations are guaranteed to return the child nodes in the same order, but the specific order used is implementation dependent and may change across different states of the same node.

      Note on cost and performance: while it is possible to iterate over all child NodeStates with the two methods NodeState.getChildNodeNames() and NodeState.getChildNode(String), this method is considered more efficient because an implementation can potentially perform the retrieval of the name and NodeState in one call. This results in O(n) vs. O(n log n) when iterating over the child node names and then look up the NodeState by name.

      Returns:
      child node entries in some stable order

    • compareAgainstBaseState

      public boolean compareAgainstBaseState(NodeState base, NodeStateDiff diff)
      Since we keep track of an explicit base node state for a ModifiedNodeState instance, we can do this in two steps: first compare all the modified properties and child nodes to those of the given base state, and then compare the base states to each other, ignoring all changed properties and child nodes that were already covered earlier.
      Specified by:
      compareAgainstBaseState in interface NodeState
      Overrides:
      compareAgainstBaseState in class AbstractNodeState
      Parameters:
      base - base state
      diff - handler of node state differences
      Returns:
      true if the full diff was performed, or false if it was aborted as requested by the handler (see the NodeStateDiff contract for more details)