net.esper.eql.join.assemble
Class BaseAssemblyNode

java.lang.Object
  net.esper.eql.join.assemble.BaseAssemblyNode

All Implemented Interfaces:

ResultAssembler

Direct Known Subclasses:

BranchOptionalAssemblyNode, BranchRequiredAssemblyNode, CartesianProdAssemblyNode, LeafAssemblyNode, RootCartProdAssemblyNode, RootOptionalAssemblyNode, RootRequiredAssemblyNode

public abstract class BaseAssemblyNode
extends Object
implements ResultAssembler

Represents a node in a tree responsible for assembling outer join query results.

The tree is double-linked, child nodes know each parent and parent know all child nodes.

Each specific subclass of this abstract assembly node is dedicated to assembling results for a certain event stream.

Field Summary

protected List<BaseAssemblyNode>	childNodes Child nodes.
protected int	numStreams Number of streams in statement.
protected ResultAssembler	parentNode Parent node.
protected int	streamNum Stream number.

Constructor Summary

protected

BaseAssemblyNode(int streamNum, int numStreams) Ctor.

Method Summary

void	addChild(BaseAssemblyNode childNode) Add a child node.
protected List<BaseAssemblyNode>	getChildNodes() Returns child nodes.
static List<BaseAssemblyNode>	getDescendentNodesBottomUp(BaseAssemblyNode topNode) Returns all descendent nodes to the top node in a list in which the utmost descendants are listed first and the top node itself is listed last.
protected ResultAssembler	getParentAssembler() Returns parent node.
protected int	getStreamNum() Returns the stream number.
protected int[]	getSubstreams() Returns an array of stream numbers that lists all child node's stream numbers.
abstract void	init(List<Node>[] result) Provides results to assembly nodes for initialization.
abstract void	print(IndentWriter indentWriter) Output this node using writer, not outputting child nodes.
void	printDescendends(IndentWriter indentWriter) Output this node and all descendent nodes using writer, outputting child nodes.
abstract void	process(List<Node>[] result) Process results.
void	setParentAssembler(ResultAssembler resultAssembler) Set parent node.

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.esper.eql.join.assemble.ResultAssembler

result

Field Detail

parentNode

protected ResultAssembler parentNode

Parent node.

childNodes

protected final List<BaseAssemblyNode> childNodes

Child nodes.

streamNum

protected final int streamNum

Stream number.

numStreams

protected final int numStreams

Number of streams in statement.

Constructor Detail

BaseAssemblyNode

protected BaseAssemblyNode(int streamNum,
                           int numStreams)

Ctor.

Parameters:

streamNum - - stream number of the event stream that this node assembles results for.

numStreams - - number of streams

Method Detail

init

public abstract void init(List<Node>[] result)

Provides results to assembly nodes for initialization.

Parameters:

result - is a list of result nodes per stream

process

public abstract void process(List<Node>[] result)

Process results.

Parameters:

result - is a list of result nodes per stream

print

public abstract void print(IndentWriter indentWriter)

Output this node using writer, not outputting child nodes.

Parameters:

indentWriter - to use for output

setParentAssembler

public void setParentAssembler(ResultAssembler resultAssembler)

Set parent node.

Parameters:

resultAssembler - is the parent node

addChild

public void addChild(BaseAssemblyNode childNode)

Add a child node.

Parameters:

childNode - to add

getStreamNum

protected int getStreamNum()

Returns the stream number.

Returns:

stream number

getChildNodes

protected List<BaseAssemblyNode> getChildNodes()

Returns child nodes.

Returns:

child nodes

getParentAssembler

protected ResultAssembler getParentAssembler()

Returns parent node.

Returns:

parent node

getSubstreams

protected int[] getSubstreams()

Returns an array of stream numbers that lists all child node's stream numbers.

Returns:

child node stream numbers

printDescendends

public void printDescendends(IndentWriter indentWriter)

Output this node and all descendent nodes using writer, outputting child nodes.

Parameters:

indentWriter - to output to

getDescendentNodesBottomUp

public static List<BaseAssemblyNode> getDescendentNodesBottomUp(BaseAssemblyNode topNode)

Returns all descendent nodes to the top node in a list in which the utmost descendants are listed first and the top node itself is listed last.

Parameters:

topNode - is the root node of a tree structure

Returns:

list of nodes with utmost descendants first ordered by level of depth in tree with top node last