Package eu.clarin.sru.server.fcs.parser

Class QueryNode

java.lang.Object

eu.clarin.sru.server.fcs.parser.QueryNode

Direct Known Subclasses:

Expression, ExpressionAnd, ExpressionGroup, ExpressionNot, ExpressionOr, ExpressionWildcard, QueryDisjunction, QueryGroup, QuerySegment, QuerySequence, QueryWithWithin, SimpleWithin

public abstract class QueryNode
extends Object

base class for FCS-QL expression tree nodes.

Field Summary

Fields

Modifier and Type	Field	Description
protected List<QueryNode>	children
protected QueryNodeType	nodeType
static int	OCCURS_UNBOUNDED	Atom occurrence it not bound.
protected QueryNode	parent

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	QueryNode(QueryNodeType nodeType)	Constructor.
protected	QueryNode(QueryNodeType nodeType, QueryNode child)	Constructor.
protected	QueryNode(QueryNodeType nodeType, List<QueryNode> children)	Constructor.

Method Summary

Modifier and Type	Method	Description
abstract void	accept(QueryVisitor visitor)
QueryNode	getChild(int idx)	Get a child node by index.
<T extends QueryNode> T	getChild(Class<T> clazz, int idx)	Get a child node of specified type by index.
int	getChildCount()	Get the number of children of this node.
List<QueryNode>	getChildren()	The children of this node.
QueryNode	getFirstChild()	Get this first child node.
<T extends QueryNode> T	getFirstChild(Class<T> clazz)	Get a first child node of specified type.
QueryNode	getLastChild()	Get this last child node.
QueryNodeType	getNodeType()	Get the node type of this node.
QueryNode	getParent()	Get the parent node of this node.
boolean	hasNodeType(QueryNodeType nodeType)	Check, if node if of given type.
protected void	setParent(QueryNode parent)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

OCCURS_UNBOUNDED

public static final int OCCURS_UNBOUNDED

Atom occurrence it not bound.

See Also:

Constant Field Values

nodeType

protected final QueryNodeType nodeType

children

protected final List<QueryNode> children

parent

protected QueryNode parent

Constructor Detail

QueryNode

protected QueryNode(QueryNodeType nodeType,
                    List<QueryNode> children)

Constructor.

Parameters:

nodeType - the type of the node

children - the children of this node or null if none

QueryNode

protected QueryNode(QueryNodeType nodeType,
                    QueryNode child)

Constructor.

Parameters:

nodeType - the type of the node

child - the child of this node or null if none

QueryNode

protected QueryNode(QueryNodeType nodeType)

Constructor.

Parameters:

nodeType - the type of the node

Method Detail

getNodeType

public QueryNodeType getNodeType()

Get the node type of this node.

Returns:

the node type

hasNodeType

public boolean hasNodeType(QueryNodeType nodeType)

Check, if node if of given type.

Parameters:

nodeType - type to check against

Returns:

true if node is of given type, false otherwise

getParent

public QueryNode getParent()

Get the parent node of this node.

Returns:

the parent node or null if this is the root node

getChildren

public List<QueryNode> getChildren()

The children of this node.

Returns:

the list of children of this node

getChildCount

public int getChildCount()

Get the number of children of this node.

Returns:

the number of children of this node

getChild

public QueryNode getChild(int idx)

Get a child node by index.

Parameters:

idx - the index of the child node

Returns:

the child node of this node or null if index is out of bounds

getFirstChild

public QueryNode getFirstChild()

Get this first child node.

Returns:

the first child node of this node or null if none

getLastChild

public QueryNode getLastChild()

Get this last child node.

Returns:

the last child node of this node or null if none

getChild

public <T extends QueryNode> T getChild(Class<T> clazz,
                                        int idx)

Get a child node of specified type by index. Only child nodes of the requested type are counted.

Type Parameters:

T - the class of the nodes to be considered

Parameters:

clazz - the type to nodes to be considered

idx - the index of the child node

Returns:

the child node of this node or null if no child was found

getFirstChild

public <T extends QueryNode> T getFirstChild(Class<T> clazz)

Get a first child node of specified type.

Type Parameters:

T - the class of the nodes to be considered

Parameters:

clazz - the type to nodes to be considered

Returns:

the child node of this node or null if no child was found

toString

public String toString()

Overrides:

toString in class Object

accept

public abstract void accept(QueryVisitor visitor)

setParent

protected final void setParent(QueryNode parent)