mondrian.olap.type
Class LevelType

java.lang.Object
  mondrian.olap.type.LevelType

All Implemented Interfaces:

Type

public class LevelType
extends Object
implements Type

The type of an expression which represents a level.

Since:

Feb 17, 2005

Author:

jhyde

Field Summary

static LevelType

Unknown

Constructor Summary

LevelType(Dimension dimension, Hierarchy hierarchy, Level level)
Creates a type representing a level.

Method Summary

Type	computeCommonType(Type type, int[] conversionCount) Returns a Type which is more general than this and the given Type.
boolean	equals(Object obj)
static LevelType	forLevel(Level level)
static LevelType	forType(Type type)
Dimension	getDimension() Returns the Dimension of this Type, or null if not known.
Hierarchy	getHierarchy() Returns the Hierarchy of this Type, or null if not known.
Level	getLevel() Returns the Level of this Type, or null if not known.
int	hashCode()
String	toString()
boolean	usesDimension(Dimension dimension, boolean definitely) Returns whether this type contains a given dimension. For example: DimensionType([Gender]) uses only the [Gender] dimension. TupleType(MemberType([Gender]), MemberType([Store])) uses [Gender] and [Store] dimensions. The definitely parameter comes into play when the dimensional information is incomplete.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

Unknown

public static final LevelType Unknown

Constructor Detail

LevelType

public LevelType(Dimension dimension,
                 Hierarchy hierarchy,
                 Level level)

Creates a type representing a level.

Parameters:

dimension - Dimension which values of this type must belong to, or null if not known

hierarchy - Hierarchy which values of this type must belong to, or null if not known

level - Level which values of this type must belong to, or null if

Method Detail

forType

public static LevelType forType(Type type)

forLevel

public static LevelType forLevel(Level level)

usesDimension

public boolean usesDimension(Dimension dimension,
                             boolean definitely)

Description copied from interface: Type

Returns whether this type contains a given dimension.

For example:

• DimensionType([Gender]) uses only the [Gender] dimension.
• TupleType(MemberType([Gender]), MemberType([Store])) uses [Gender] and [Store] dimensions.

The definitely parameter comes into play when the dimensional information is incomplete. For example, when applied to TupleType(MemberType(null), MemberType([Store])), usesDimension([Gender], false) returns true because it is possible that the expression returns a member of the [Gender] dimension; but usesDimension([Gender], true) returns true because it is possible that the expression returns a member of the [Gender] dimension.

Specified by:

usesDimension in interface Type

Parameters:

dimension - Dimension

definitely - If true, returns true only if this type definitely uses the dimension

Returns:

whether this Type uses the given Dimension

getDimension

public Dimension getDimension()

Description copied from interface: Type

Returns the Dimension of this Type, or null if not known. If not applicable, throws.

Specified by:

getDimension in interface Type

Returns:

the Dimension of this Type, or null if not known.

getHierarchy

public Hierarchy getHierarchy()

Description copied from interface: Type

Returns the Hierarchy of this Type, or null if not known. If not applicable, throws.

Specified by:

getHierarchy in interface Type

Returns:

the Hierarchy of this type, or null if not known

getLevel

public Level getLevel()

Description copied from interface: Type

Returns the Level of this Type, or null if not known. If not applicable, throws.

Specified by:

getLevel in interface Type

Returns:

the Level of this Type

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

computeCommonType

public Type computeCommonType(Type type,
                              int[] conversionCount)

Description copied from interface: Type

Returns a Type which is more general than this and the given Type. The type returned is broad enough to hold any value of either type, but no broader. If there is no such type, returns null.

Some examples:

• The common type for StringType and NumericType is ScalarType.
• The common type for NumericType and DecimalType(4, 2) is NumericType.
• DimensionType and NumericType have no common type.

If conversionCount is not null, implicit conversions such as HierarchyType to DimensionType are considered; the parameter is incremented by the number of conversions performed.

Some examples:

• The common type for HierarchyType(hierarchy=Time.Weekly) and LevelType(dimension=Time), if conversions are allowed, is HierarchyType(dimension=Time).

One use of common types is to determine the types of the arguments to the Iif function. For example, the call

Iif(1 > 2, [Measures].[Unit Sales], 5)

has type ScalarType, because DecimalType(-1, 0) is a subtype of ScalarType, and MeasureType can be converted implicitly to ScalarType.

Specified by:

computeCommonType in interface Type

Parameters:

type - Type

conversionCount - Number of conversions; output parameter that is incremented each time a conversion is performed; if null, conversions are not considered

Returns:

More general type