edu.ucla.sspace.dependency

Class DependencyIterator

java.lang.Object

edu.ucla.sspace.dependency.DependencyIterator

All Implemented Interfaces:

Iterator<DependencyPath>

public class DependencyIterator
extends Object
implements Iterator<DependencyPath>

A traversal class for iterating over a dependency tree of Relations. Given the tree and a starting index, the traverser will find all paths that satisfy several different criteria: length of the path and accepted relations in the path.

Note that this class is NOT thread safe.

Field Summary

Fields

Modifier and Type	Field and Description
protected Queue<SimpleDependencyPath>	frontier The paths that have been expanded from the starting node but have not yet been returned.

Constructor Summary

Constructors

Constructor and Description
DependencyIterator(DependencyTreeNode startNode, DependencyRelationAcceptor acceptor, int maxPathLength) Creates a new DependencyIterator that will return all DependencyPaths rooted at the term with index startTerm.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	hasNext() Returns true if there are still paths to return for the tree.
DependencyPath	next() Returns the next DependencyPath in the tree whose length is equal or greater than the previously returned path.
void	remove() Throws an UnsupportedOperationException if called

Methods inherited from class java.lang.Object

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

Field Detail

frontier

protected final Queue<SimpleDependencyPath> frontier

The paths that have been expanded from the starting node but have not yet been returned.

Constructor Detail

DependencyIterator

public DependencyIterator(DependencyTreeNode startNode,
                  DependencyRelationAcceptor acceptor,
                  int maxPathLength)

Creates a new DependencyIterator that will return all DependencyPaths rooted at the term with index startTerm. Each link in the path will be valied with acceptor and weighted with weighter. Each path will have length 1 + maxPathLength.

Parameters:

startNode - the node that will start all the paths to be generated.

acceptor - The DependencyRelationAcceptor that will validate each link the a path

maxPathLength - the maximum length of any path returned

Throws:

IllegalArgumentException - if maxPathLength is less than 1

Method Detail

hasNext

public boolean hasNext()

Returns true if there are still paths to return for the tree.

Specified by:

hasNext in interface Iterator<DependencyPath>

next

public DependencyPath next()

Returns the next DependencyPath in the tree whose length is equal or greater than the previously returned path.

Specified by:

next in interface Iterator<DependencyPath>

remove

public void remove()

Throws an UnsupportedOperationException if called

Specified by:

remove in interface Iterator<DependencyPath>