EmptyNodeState (Oak NodeStore and Commit SPI 1.7.14 API)

java.lang.Object
- org.apache.jackrabbit.oak.plugins.memory.EmptyNodeState

All Implemented Interfaces:

NodeState
```
public final class EmptyNodeState
extends Object
implements NodeState
```
Singleton instances of empty and non-existent node states, i.e. ones with neither properties nor child nodes.

Field Summary

Fields
Modifier and Type Field and Description

static NodeState EMPTY_NODE

static NodeState MISSING_NODE
- Fields inherited from interface org.apache.jackrabbit.oak.spi.state.NodeState
  EXISTS

Fields
Modifier and Type	Field and Description
`static NodeState`	`EMPTY_NODE`
`static NodeState`	`MISSING_NODE`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`NodeBuilder`	`builder()` Returns a builder for constructing a new node state based on this state, i.e.
`boolean`	`compareAgainstBaseState(NodeState base, NodeStateDiff diff)` Compares this node state against the given base state.
`static boolean`	`compareAgainstEmptyState(NodeState state, NodeStateDiff diff)`
`boolean`	`equals(Object object)`
`boolean`	`exists()` Checks whether this node exists.
`boolean`	`getBoolean(String name)` Returns the boolean value of the named property.
`NodeState`	`getChildNode(String name)` Returns the named, possibly non-existent, child node.
`long`	`getChildNodeCount(long max)` Returns the number of iterable child nodes of this node.
`Iterable<? extends ChildNodeEntry>`	`getChildNodeEntries()` Returns the iterable child node entries of this instance.
`Iterable<String>`	`getChildNodeNames()` Returns the names of all iterable child nodes.
`long`	`getLong(String name)` Returns the long value of the named property.
`String`	`getName(String name)` Returns the name value of the named property.
`Iterable<String>`	`getNames(String name)` Returns the name values of the named property.
`Iterable<? extends org.apache.jackrabbit.oak.api.PropertyState>`	`getProperties()` Returns an iterable of the properties of this node.
`org.apache.jackrabbit.oak.api.PropertyState`	`getProperty(String name)` Returns the named property, or `null` if no such property exists.
`long`	`getPropertyCount()` Returns the number of properties of this node.
`String`	`getString(String name)` Returns the string value of the named property.
`Iterable<String>`	`getStrings(String name)` Returns the string values of the named property.
`boolean`	`hasChildNode(String name)` Checks whether the named child node exists.
`int`	`hashCode()`
`boolean`	`hasProperty(String name)` Checks whether the named property exists.
`static boolean`	`isEmptyState(NodeState state)`
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - EMPTY_NODE
```
public static final NodeState EMPTY_NODE
```
  - MISSING_NODE
```
public static final NodeState MISSING_NODE
```
- Method Detail
  - exists
```
public boolean exists()
```
    Description copied from interface: NodeState
    
    Checks whether this node exists. See the above discussion about the existence of node states.
    
    Specified by:
    
    exists in interface NodeState
    
    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
    
    Returns:
    
    number of properties
  - hasProperty
```
public boolean hasProperty(@Nonnull
                           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
    
    Parameters:
    
    name - property name
    
    Returns:
    
    true if the named property exists, false otherwise
  - getProperty
```
@CheckForNull
public org.apache.jackrabbit.oak.api.PropertyState getProperty(@Nonnull
                                                                             String name)
```
    Description copied from interface: NodeState
    
    Returns the named property, or null if no such property exists.
    
    Specified by:
    
    getProperty in interface NodeState
    
    Parameters:
    
    name - name of the property to return
    
    Returns:
    
    named property, or null if not found
  - getBoolean
```
public boolean getBoolean(@Nonnull
                          String name)
```
    Description copied from interface: NodeState
    Returns the boolean value of the named property. The implementation is equivalent to the following code, but may be optimized.
```
 
 PropertyState property = state.getProperty(name);
 return property != null
     && property.getType() == Type.BOOLEAN
     && property.getValue(Type.BOOLEAN);
 
 
```
    Specified by:
    
    getBoolean in interface NodeState
    
    Parameters:
    
    name - property name
    
    Returns:
    
    boolean value of the named property, or false
  - getLong
```
public long getLong(String name)
```
    Description copied from interface: NodeState
    Returns the long value of the named property. The implementation is equivalent to the following code, but may be optimized.
```
 
 PropertyState property = state.getProperty(name);
 if (property != null && property.getType() == Type.LONG) {
     return property.getValue(Type.LONG);
 } else {
     return 0;
 }
 
 
```
    Specified by:
    
    getLong in interface NodeState
    
    Parameters:
    
    name - property name
    
    Returns:
    
    long value of the named property, or zero
  - getString
```
public String getString(String name)
```
    Description copied from interface: NodeState
    Returns the string value of the named property. The implementation is equivalent to the following code, but may be optimized.
```
 
 PropertyState property = state.getProperty(name);
 if (property != null && property.getType() == Type.STRING) {
     return property.getValue(Type.STRING);
 } else {
     return null;
 }
 
 
```
    Specified by:
    
    getString in interface NodeState
    
    Parameters:
    
    name - property name
    
    Returns:
    
    string value of the named property, or null
  - getStrings
```
@Nonnull
public Iterable<String> getStrings(@Nonnull
                                            String name)
```
    Description copied from interface: NodeState
    Returns the string values of the named property. The implementation is equivalent to the following code, but may be optimized.
```
 
 PropertyState property = state.getProperty(name);
 if (property != null && property.getType() == Type.STRINGS) {
     return property.getValue(Type.STRINGS);
 } else {
     return Collections.emptyList();
 }
 
 
```
    Specified by:
    
    getStrings in interface NodeState
    
    Parameters:
    
    name - property name
    
    Returns:
    
    string values of the named property, or an empty collection
  - getName
```
@CheckForNull
public String getName(@Nonnull
                                    String name)
```
    Description copied from interface: NodeState
    Returns the name value of the named property. The implementation is equivalent to the following code, but may be optimized.
```
 
 PropertyState property = state.getProperty(name);
 if (property != null && property.getType() == Type.NAME) {
     return property.getValue(Type.NAME);
 } else {
     return null;
 }
 
 
```
    Specified by:
    
    getName in interface NodeState
    
    Parameters:
    
    name - property name
    
    Returns:
    
    name value of the named property, or null
  - getNames
```
@Nonnull
public Iterable<String> getNames(@Nonnull
                                          String name)
```
    Description copied from interface: NodeState
    Returns the name values of the named property. The implementation is equivalent to the following code, but may be optimized.
```
 
 PropertyState property = state.getProperty(name);
 if (property != null && property.getType() == Type.NAMES) {
     return property.getValue(Type.NAMES);
 } else {
     return Collections.emptyList();
 }
 
 
```
    Specified by:
    
    getNames in interface NodeState
    
    Parameters:
    
    name - property name
    
    Returns:
    
    name values of the named property, or an empty collection
  - getProperties
```
@Nonnull
public Iterable<? extends org.apache.jackrabbit.oak.api.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.
    
    Specified by:
    
    getProperties in interface NodeState
    
    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
    
    Parameters:
    
    max - the maximum number of entries to traverse
    
    Returns:
    
    number of iterable child nodes
  - hasChildNode
```
public boolean hasChildNode(@Nonnull
                            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.
    
    Specified by:
    
    hasChildNode in interface NodeState
    
    Parameters:
    
    name - name of the child node
    
    Returns:
    
    true if the named child node exists, false otherwise
  - getChildNode
```
@Nonnull
public NodeState getChildNode(@Nonnull
                                       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.
    
    Specified by:
    
    getChildNode in interface NodeState
    
    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
    
    Returns:
    
    child node names in some stable order
  - getChildNodeEntries
```
@Nonnull
public 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.
    
    Specified by:
    
    getChildNodeEntries in interface NodeState
    
    Returns:
    
    child node entries in some stable order
  - builder
```
@Nonnull
public 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.
    
    Specified by:
    
    builder in interface NodeState
    
    Returns:
    
    node builder based on this state
  - compareAgainstBaseState
```
public boolean compareAgainstBaseState(NodeState base,
                                       NodeStateDiff diff)
```
    Description copied from interface: NodeState
    
    Compares this node state against the given base state. Any differences are reported by calling the relevant added/changed/deleted methods of the given handler.
    TODO: Define the behavior of this method with regards to iterability/existence of child nodes.
    
    Specified by:
    
    compareAgainstBaseState in interface NodeState
    
    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)
  - compareAgainstEmptyState
```
public static boolean compareAgainstEmptyState(NodeState state,
                                               NodeStateDiff diff)
```
  - isEmptyState
```
public static boolean isEmptyState(NodeState state)
```
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - equals
```
public boolean equals(Object object)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object

Class EmptyNodeState

Field Summary

Fields inherited from interface org.apache.jackrabbit.oak.spi.state.NodeState

Method Summary

Methods inherited from class java.lang.Object

Field Detail

EMPTY_NODE

MISSING_NODE

Method Detail

exists

getPropertyCount

hasProperty

getProperty

getBoolean

getLong

getString

getStrings

getName

getNames

getProperties

getChildNodeCount

hasChildNode

getChildNode

getChildNodeNames

getChildNodeEntries

builder

compareAgainstBaseState

compareAgainstEmptyState

isEmptyState

toString

equals

hashCode