org.olap4j.mdx
Class LiteralNode

java.lang.Object
  org.olap4j.mdx.LiteralNode

All Implemented Interfaces:

ParseTreeNode

public class LiteralNode
extends Object
implements ParseTreeNode

Represents a constant value, such as a string or number, in a parse tree.

Symbols, such as the ASC keyword in Order([Store].Members, [Measures].[Unit Sales], ASC), are also represented as Literals.

A LiteralNode is immutable.

Version:

$Id: LiteralNode.java 482 2012-01-05 23:27:27Z jhyde $

Author:

jhyde

Method Summary

<T> T	accept(ParseTreeVisitor<T> visitor) Accepts a visitor to this MDX parse tree node.
static LiteralNode	createNull(ParseRegion region) Creates a literal with the NULL value.
static LiteralNode	createNumeric(ParseRegion region, BigDecimal value, boolean approximate) Creates a numeric literal.
static LiteralNode	createString(ParseRegion region, String value) Creates a string literal.
static LiteralNode	createSymbol(ParseRegion region, String value) Creates a symbol literal.
LiteralNode	deepCopy() Creates a deep copy of this ParseTreeNode object.
ParseRegion	getRegion() Returns the region of the source code which this node was created from, if it was created by parsing.
Type	getType() Returns the type of this expression.
Object	getValue() Returns the value of this literal.
void	unparse(ParseTreeWriter writer) Converts this node into MDX text.

Methods inherited from class java.lang.Object

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

Method Detail

createNull

public static LiteralNode createNull(ParseRegion region)

Creates a literal with the NULL value.

Parameters:

region - Region of source code

Returns:

literal representing the NULL value

createString

public static LiteralNode createString(ParseRegion region,
                                       String value)

Creates a string literal.

Parameters:

region - Region of source code

value - String value

Returns:

literal representing the string value

See Also:

createSymbol(org.olap4j.mdx.ParseRegion, java.lang.String)

createSymbol

public static LiteralNode createSymbol(ParseRegion region,
                                       String value)

Creates a symbol literal.

Parameters:

region - Region of source code

value - Name of symbol

Returns:

literal representing the symbol value

See Also:

createString(org.olap4j.mdx.ParseRegion, java.lang.String)

createNumeric

public static LiteralNode createNumeric(ParseRegion region,
                                        BigDecimal value,
                                        boolean approximate)

Creates a numeric literal.

Parameters:

region - Region of source code

value - Value of literal; must not be null

approximate - Whether the literal is approximate

Returns:

literal representing the integer value

accept

public <T> T accept(ParseTreeVisitor<T> visitor)

Description copied from interface: ParseTreeNode

Accepts a visitor to this MDX parse tree node.

The implementation should generally dispatches to the ParseTreeVisitor.visit(org.olap4j.mdx.SelectNode) method appropriate to the type of expression.

Specified by:

accept in interface ParseTreeNode

Parameters:

visitor - Visitor

Returns:

T, the specific return type of the visitor

getType

public Type getType()

Description copied from interface: ParseTreeNode

Returns the type of this expression.

Returns null if this node is not an expression, for instance a SELECT node.

Specified by:

getType in interface ParseTreeNode

Returns:

type of this expression

getRegion

public ParseRegion getRegion()

Description copied from interface: ParseTreeNode

Returns the region of the source code which this node was created from, if it was created by parsing.

A non-leaf node's region will encompass the regions of all of its children. For example, a the region of a function call node Crossjoin([Gender], {[Store].[USA]}) stretches from the first character of the function name to the closing parenthesis.

Region may be null, if the node was created programmatically, not from a piece of source code.

Specified by:

getRegion in interface ParseTreeNode

Returns:

Region of the source code this node was created from, if it was created by parsing

getValue

public Object getValue()

Returns the value of this literal.

Value is always of type String (if the literal is a string or a symbol), of type BigDecimal (if the literal is numeric), or null (if the literal is of null type).

Returns:

value

unparse

public void unparse(ParseTreeWriter writer)

Description copied from interface: ParseTreeNode

Converts this node into MDX text.

Specified by:

unparse in interface ParseTreeNode

Parameters:

writer - Parse tree writer

deepCopy

public LiteralNode deepCopy()

Description copied from interface: ParseTreeNode

Creates a deep copy of this ParseTreeNode object.

Note: implementing classes can return the concrete type instead of ParseTreeNode (using Java 1.5 covariant return types)

Specified by:

deepCopy in interface ParseTreeNode

Returns:

The deep copy of this ParseTreeNode