[Java] Class Node

groovy.util.Node

All Implemented Interfaces and Traits:: Serializable, Cloneable

public class Node
extends Object

Represents an arbitrary tree node which can be used for structured metadata or any arbitrary XML-like tree. A node can have a name, a value and an optional Map of attributes. Typically the name is a String and a value is either a String or a List of other Nodes, though the types are extensible to provide a flexible structure, e.g. you could use a QName as the name which includes a namespace URI and a local name. Or a JMX ObjectName etc. So this class can represent metadata like {foo a=1 b="abc"} or nested metadata like {foo a=1 b="123" { bar x=12 text="hello" }}

Authors:: James Strachan; Paul King

Constructor Summary

Constructors
Constructor and description
`Node (Node parent, Object name)` Creates a new Node named `name` and if a parent is supplied, adds the newly created node as a child of the parent.
`Node (Node parent, Object name, Object value)` Creates a new Node named `name` with value `value` and if a parent is supplied, adds the newly created node as a child of the parent.
`Node (Node parent, Object name, Map attributes)` Creates a new Node named `name` with attributes specified in the `attributes` Map.
`Node (Node parent, Object name, Map attributes, Object value)` Creates a new Node named `name` with value `value` and with attributes specified in the `attributes` Map.

Methods Summary

Methods
Type Params	Return Type	Name and description
	`boolean`	`append(Node child)` Appends a child to the current node.
	`Node`	`appendNode(Object name, Map attributes)` Creates a new node as a child of the current node.
	`Node`	`appendNode(Object name)` Creates a new node as a child of the current node.
	`Node`	`appendNode(Object name, Object value)` Creates a new node as a child of the current node.
	`Node`	`appendNode(Object name, Map attributes, Object value)` Creates a new node as a child of the current node.
	`Object`	`attribute(Object key)` Provides lookup of attributes by key.
	`Map`	`attributes()` Returns a `Map` of the attributes of the node or an empty `Map` if the node does not have any attributes.
	`List`	`breadthFirst()` Provides a collection of all the nodes in the tree using a breadth-first traversal.
	`List`	`children()` Returns a `List` of the nodes children.
	`Object`	`clone()` Creates a new Node with the same name, no parent, shallow cloned attributes and if the value is a NodeList, a (deep) clone of those nodes.
	`List`	`depthFirst()` Provides a collection of all the nodes in the tree using a depth first traversal.
	`Object`	`get(String key)` Provides lookup of elements by non-namespaced name
	`NodeList`	`getAt(QName name)` Provides lookup of elements by QName.
	`Iterator`	`iterator()` Returns an `Iterator` of the children of the node.
	`List<String>`	`localText()` Returns the list of any direct String nodes of this node.
	`Object`	`name()` Returns an `Object` representing the name of the node.
	`Node`	`parent()` Returns the parent of the node.
	`void`	`plus(Closure c)` Adds sibling nodes (defined using builder-style notation via a Closure) after the current node.
	`void`	`print(PrintWriter out)` Writes the node to the specified `PrintWriter`.
	`boolean`	`remove(Node child)` Removes a child of the current node.
	`Node`	`replaceNode(Closure c)` Replaces the current node with nodes defined using builder-style notation via a Closure.
	`Node`	`replaceNode(Node n)` Replaces the current node with the supplied node.
	`protected static void`	`setMetaClass(MetaClass metaClass, Class nodeClass)` Extension point for subclasses to override the metaclass.
	`protected void`	`setParent(Node parent)` Adds or replaces the parent of the node.
	`void`	`setValue(Object value)` Adds or replaces the value of the node.
	`String`	`text()` Returns the textual representation of the current node and all its child nodes.
	`String`	`toString()`
	`Object`	`value()` Returns an `Object` representing the value of the node.

Inherited Methods Summary

Inherited Methods
Methods inherited from class	Name
`class Object`	`wait, wait, wait, equals, toString, hashCode, getClass, notify, notifyAll`

Constructor Detail

public Node(Node parent, Object name)

Creates a new Node named name and if a parent is supplied, adds the newly created node as a child of the parent.

Parameters:: parent - the parent node or null if no parent; name - the name of the node

public Node(Node parent, Object name, Object value)

Creates a new Node named name with value value and if a parent is supplied, adds the newly created node as a child of the parent.

Parameters:: parent - the parent node or null if no parent; name - the name of the node; value - the Node value, e.g. some text but in general any Object

public Node(Node parent, Object name, Map attributes)

Creates a new Node named name with attributes specified in the attributes Map. If a parent is supplied, the newly created node is added as a child of the parent.

Parameters:: parent - the parent node or null if no parent; name - the name of the node; attributes - a Map of name-value pairs

public Node(Node parent, Object name, Map attributes, Object value)

Creates a new Node named name with value value and with attributes specified in the attributes Map. If a parent is supplied, the newly created node is added as a child of the parent.

Parameters:: parent - the parent node or null if no parent; name - the name of the node; attributes - a Map of name-value pairs; value - the Node value, e.g. some text but in general any Object

Method Detail

public boolean append(Node child)

Appends a child to the current node.

Parameters:: child - the child to append

Returns:: true

public Node appendNode(Object name, Map attributes)

Creates a new node as a child of the current node.

Parameters:: name - the name of the new node; attributes - the attributes of the new node

Returns:: the newly created Node

public Node appendNode(Object name)

Creates a new node as a child of the current node.

Parameters:: name - the name of the new node

Returns:: the newly created Node

public Node appendNode(Object name, Object value)

Creates a new node as a child of the current node.

Parameters:: name - the name of the new node; value - the value of the new node

Returns:: the newly created Node

public Node appendNode(Object name, Map attributes, Object value)

Creates a new node as a child of the current node.

Parameters:: name - the name of the new node; attributes - the attributes of the new node; value - the value of the new node

Returns:: the newly created Node

public Object attribute(Object key)

Provides lookup of attributes by key.

Parameters:: key - the key of interest

Returns:: the attribute matching the key or null if no match exists

public Map attributes()

Returns a Map of the attributes of the node or an empty Map if the node does not have any attributes.

Returns:: the attributes of the node

public List breadthFirst()

Provides a collection of all the nodes in the tree using a breadth-first traversal.

Returns:: the list of (breadth-first) ordered nodes

public List children()

Returns a List of the nodes children.

Returns:: the nodes children

@Override public Object clone()

Creates a new Node with the same name, no parent, shallow cloned attributes and if the value is a NodeList, a (deep) clone of those nodes.

Returns:: the clone

public List depthFirst()

Provides a collection of all the nodes in the tree using a depth first traversal.

Returns:: the list of (depth-first) ordered nodes

public Object get(String key)

Provides lookup of elements by non-namespaced name

Parameters:: key - the name (or shortcut key) of the node(s) of interest

Returns:: the nodes which match key

public NodeList getAt(QName name)

Provides lookup of elements by QName.

Parameters:: name - the QName of interest

Returns:: the nodes matching name

public Iterator iterator()

Returns an Iterator of the children of the node.

Returns:: the iterator of the nodes children

public List<String> localText()

Returns the list of any direct String nodes of this node.

Returns:: the list of String values from this node

Since:: 2.3.0

public Object name()

Returns an Object representing the name of the node.

Returns:: the name or null if name is empty

public Node parent()

Returns the parent of the node.

Returns:: the parent or null for the root node

public void plus(Closure c)

Adds sibling nodes (defined using builder-style notation via a Closure) after the current node.

Parameters:: c - A Closure defining the new sibling nodes to add using builder-style notation.

public void print(PrintWriter out)

Writes the node to the specified PrintWriter.

Parameters:: out - the writer receiving the output

public boolean remove(Node child)

Removes a child of the current node.

Parameters:: child - the child to remove

Returns:: true if the param was a child of the current node

public Node replaceNode(Closure c)

Replaces the current node with nodes defined using builder-style notation via a Closure.

Parameters:: c - A Closure defining the new nodes using builder-style notation.

Returns:: the original now replaced node

public Node replaceNode(Node n)

Replaces the current node with the supplied node.

Parameters:: n - the new Node

Returns:: the original now replaced node

protected static void setMetaClass(MetaClass metaClass, Class nodeClass)

Extension point for subclasses to override the metaclass. The default one supports the property and @ attribute notations.

Parameters:: metaClass - the original metaclass; nodeClass - the class whose metaclass we wish to override (this class or a subclass)

protected void setParent(Node parent)

Adds or replaces the parent of the node.

Parameters:: parent - the new parent of the node

public void setValue(Object value)

Adds or replaces the value of the node.

Parameters:: value - the new value of the node

public String text()

Returns the textual representation of the current node and all its child nodes.

Returns:: the text value of the node including child text

public String toString()

public Object value()

Returns an Object representing the value of the node.

Returns:: the value or null if value is empty

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Licensed under the Apache license.
https://docs.groovy-lang.org/2.4.21/html/gapi/groovy/util/Node.html