com.northconcepts.datapipeline.core

Class Node

java.lang.Object

com.northconcepts.datapipeline.core.Node

All Implemented Interfaces:

Session, Serializable

Direct Known Subclasses:

Field, ValueNode

public abstract class Node
extends Object
implements Session, Serializable

Node is the base class for all persistent data in Data Pipeline. It is the superclass for records, fields, arrays, and values.

See Also:

Record, Field, ArrayValue, SingleValue, ValueNode, Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Node.DuplicateNodeAction DuplicateNodeAction lists all actions that can be taken automatically when a target field already exists during a record copy or lookup.
static class	Node.NodeType NodeType lists all concrete data node types used in Data Pipeline.

Nested classes/interfaces inherited from interface com.northconcepts.datapipeline.core.Session

Session.SessionImpl

Field Summary

Fields

Modifier and Type	Field and Description
protected Session.SessionImpl	session

Constructor Summary

Constructors

Constructor and Description
Node()

Method Summary

Modifier and Type	Method and Description
protected void	assertNotAncestorOf(Node parentNode)
<T> boolean	containsSessionProperty(Class<T> type) Returns true if a session property exists for the given type.
<T> boolean	containsSessionProperty(Class<T> type, String name) Returns true if a session property exists for the given type and name combination.
boolean	containsSessionProperty(String name) Returns true if a session property exists with the given name.
void	copySessionPropertiesFrom(Session sourceSession) Copies all session properties from the given source session into this one.
int	getNodeDepth() Returns this node's distance from its root node.
abstract Node.NodeType	getNodeType() Returns the concrete Node.NodeType of this node.
Field	getParentField() Returns the closest parent record's field that this node is the child of, otherwise null if one does not exist.
abstract Node	getParentNode() Returns the parent node that this node belongs to, or null if this is a root node.
Record	getParentRecord() Returns the closest parent record that this node is the child of, otherwise null if one does not exist.
<T> T	getSessionProperty(Class<T> type) Returns the session property value associated with the given type.
<T> T	getSessionProperty(Class<T> type, String name) Returns the session property value associated with the given type and name combination.
<T> T	getSessionProperty(String name) Returns the session property value associated with the given name.
abstract boolean	hasChildNodes() Returns true if this node contains any sub nodes.
abstract boolean	hasChildRecords() Returns true if this node contains any descendant, record nodes.
boolean	isAncestorOf(Node node) Returns true if the supplied node is a descendant of this one.
boolean	isChildNode() Indicates if this record has a parent record (i.e.
abstract boolean	isNotNull() Returns true if this node does not contain a null value.
abstract boolean	isNull() Returns true if this node contains a null value.
boolean	isValueNode() Returns true if this node is a ValueNode (Record, ArrayValue, or SingleValue).
Set<String>	keySet() Returns the set of all session property keys.
protected abstract void	removeChildNode(Node child)
void	removeSessionProperties() Removes all session properties from this session.
<T> void	setSessionProperty(Class<T> type, Object value) Sets a session property value keyed by type.
<T> void	setSessionProperty(Class<T> type, String name, Object value) Sets a session property value keyed by the given type and name combination.
void	setSessionProperty(String name, Object value) Sets a session property value keyed by name.
abstract String	toString() Returns a human-readable string representation of this node and its contents.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

session

protected transient Session.SessionImpl session

Constructor Detail

Node

public Node()

Method Detail

getParentNode

public abstract Node getParentNode()

Returns the parent node that this node belongs to, or null if this is a root node.

Returns:

the parent node, or null

removeChildNode

protected abstract void removeChildNode(Node child)

isNull

public abstract boolean isNull()

Returns true if this node contains a null value. In concrete terms, only Field and SingleValue can contain nulls while not being null themselves. Both Record and ArrayValue will return false even if they have no values or null only values.

isNotNull

public abstract boolean isNotNull()

Returns true if this node does not contain a null value. In concrete terms, only Field and SingleValue can contain nulls while not being null themselves. Both Record and ArrayValue will return true even if they have no values or null only values.

getParentField

public Field getParentField()

Returns the closest parent record's field that this node is the child of, otherwise null if one does not exist.

See Also:

getParentRecord(), isChildNode(), hasChildRecords(), getNodeDepth(), Field.getValueAsRecord(), Field.getValueAsRecord()

getParentRecord

public Record getParentRecord()

Returns the closest parent record that this node is the child of, otherwise null if one does not exist.

See Also:

getParentField(), isChildNode(), hasChildRecords(), getNodeDepth(), Field.getValueAsRecord(), Field#getValueAsRecords()

getNodeType

public abstract Node.NodeType getNodeType()

Returns the concrete Node.NodeType of this node.

Returns:

the node type, never null

isChildNode

public boolean isChildNode()

Indicates if this record has a parent record (i.e. this record is part of a hierarchical structure). If this method returns true, getParentField() can be used to retrieve the parent record's field that this record is attached to.

See Also:

getParentField(), getParentRecord(), hasChildRecords(), #getRecordDepth(), Field.getValueAsRecord(), Field#getValueAsRecords()

hasChildNodes

public abstract boolean hasChildNodes()

Returns true if this node contains any sub nodes.

hasChildRecords

public abstract boolean hasChildRecords()

Returns true if this node contains any descendant, record nodes.

getNodeDepth

public int getNodeDepth()

Returns this node's distance from its root node. It returns 0 if it is the root node (i.e. it has no parents), 1 if it is the direct child of the root node, 2 if it is the grandchild of the root, and so on.

isAncestorOf

public boolean isAncestorOf(Node node)

Returns true if the supplied node is a descendant of this one.

assertNotAncestorOf

protected void assertNotAncestorOf(Node parentNode)

isValueNode

public boolean isValueNode()

Returns true if this node is a ValueNode (Record, ArrayValue, or SingleValue).

toString

public abstract String toString()

Returns a human-readable string representation of this node and its contents.

Overrides:

toString in class Object

Returns:

a string representation of this node

keySet

public Set<String> keySet()

Returns the set of all session property keys.

Returns the set of session property keys stored on this node. Returns an empty set if no session properties have been assigned.

Specified by:

keySet in interface Session

Returns:

the set of property keys, never null

containsSessionProperty

public <T> boolean containsSessionProperty(Class<T> type,
                                           String name)

Returns true if a session property exists for the given type and name combination.

Specified by:

containsSessionProperty in interface Session

Type Parameters:

T - the type used as part of the property key

Parameters:

type - the class used as part of the property key, or null to match by name only

name - the property name, or null to match by type only

Returns:

true if the property exists

containsSessionProperty

public <T> boolean containsSessionProperty(Class<T> type)

Returns true if a session property exists for the given type.

Specified by:

containsSessionProperty in interface Session

Type Parameters:

T - the type used as the property key

Parameters:

type - the class used as the property key

Returns:

true if the property exists

containsSessionProperty

public boolean containsSessionProperty(String name)

Returns true if a session property exists with the given name.

Specified by:

containsSessionProperty in interface Session

Parameters:

name - the property name

Returns:

true if the property exists

copySessionPropertiesFrom

public void copySessionPropertiesFrom(Session sourceSession)

Copies all session properties from the given source session into this one.

Copies all session properties from the given source session into this node's session. If the source session is null or empty, this method does nothing.

Specified by:

copySessionPropertiesFrom in interface Session

Parameters:

sourceSession - the source session to copy from, may be null

removeSessionProperties

public void removeSessionProperties()

Removes all session properties from this session.

Removes all session properties from this node by discarding the internal session store.

Specified by:

removeSessionProperties in interface Session

getSessionProperty

public <T> T getSessionProperty(Class<T> type,
                                String name)

Returns the session property value associated with the given type and name combination.

Specified by:

getSessionProperty in interface Session

Type Parameters:

T - the expected value type

Parameters:

type - the class used as part of the property key, or null to match by name only

name - the property name, or null to match by type only

Returns:

the property value, or null if not found

getSessionProperty

public <T> T getSessionProperty(Class<T> type)

Returns the session property value associated with the given type.

Specified by:

getSessionProperty in interface Session

Type Parameters:

T - the expected value type

Parameters:

type - the class used as the property key

Returns:

the property value, or null if not found

getSessionProperty

public <T> T getSessionProperty(String name)

Returns the session property value associated with the given name.

Specified by:

getSessionProperty in interface Session

Type Parameters:

T - the expected value type

Parameters:

name - the property name

Returns:

the property value, or null if not found

setSessionProperty

public <T> void setSessionProperty(Class<T> type,
                                   String name,
                                   Object value)

Sets a session property value keyed by the given type and name combination.

Specified by:

setSessionProperty in interface Session

Type Parameters:

T - the type used as part of the property key

Parameters:

type - the class used as part of the property key, or null to match by name only

name - the property name, or null to match by type only

value - the value to store

setSessionProperty

public <T> void setSessionProperty(Class<T> type,
                                   Object value)

Sets a session property value keyed by type.

Specified by:

setSessionProperty in interface Session

Type Parameters:

T - the type used as the property key

Parameters:

type - the class used as the property key

value - the value to store

setSessionProperty

public void setSessionProperty(String name,
                               Object value)

Sets a session property value keyed by name.

Specified by:

setSessionProperty in interface Session

Parameters:

name - the property name

value - the value to store