Overview  Package   Class  Use  Deprecated  Index
Home >> All >> org >> jdaemon >> [ era overview ]	PREV CLASS  NEXT CLASS
SUMMARY:  JAVADOC |  SOURCE |  DOWNLOAD | NESTED | FIELD | CONSTR | METHOD	DETAIL: FIELD | CONSTR | METHOD

---

org.jdaemon.era
Interface Cube  

All Superinterfaces:

java.util.Collection, java.lang.Iterable

All Known Implementing Classes:

AbstractCube

---

public interface Cube

extends java.util.Collection

Interface to support generic slicing-and-dicing of data using an OLAP cube metaphor. A cube contains a collection of data items of some type (In principle any java object). Each object within the collection is assumed to have a set of named attriubutes; Subsets of this data collection can be generated either through an arbitrary filtering mechanism or through placing standardised constraints on object attribute values.

---

Field Summary
static int	EQUAL           operator that selects objects with attribute equal to a value
static int	GREATER           operator that selects objects with attribute greater than a value
static int	GREATER_OR_EQUAL           operator that selects objects with attribute greater than equal to a value
static int	LAST_OPERAND
static int	LESS           operator that selects objects with attribute less than a value
static int	LESS_OR_EQUAL           operator that selects objects with attribute less than or equal to a value

 

Method Summary
void	addAll(Cube cube)           Add all the data items in the given Cube to this cube.
Cube	constrain(Filter filter)           Creates a new cube containing some subset of the contents of this cube.
Cube	constrain(java.lang.String attribute, int operator, java.lang.Object operand)           Creates a new cube containing some subset of the contents of this cube.
java.lang.Object	getAttribute(java.lang.String attribute, java.lang.Object object)           Get the value of an individual attribute of an object contained by this cube.
java.util.SortedSet	getAttributeSet(java.lang.String attribute)           Get a set of all the values of a given attribute across all contained objects.
CubeDescriptor	getDescriptor()           Get metadata describing this cube.
java.lang.Object	getMax(java.lang.String attribute)           Get the maximum value over all contained objects of some attribute.
java.lang.Object	getMin(java.lang.String attribute)           Get the minimum value over all contained objects of some attribute.
double	getSum(java.lang.String attribute)           Gets the sum over all contained objects of some attributes.
java.util.Iterator	groupBy(java.lang.String attribute)           Group data by a given attribute.
java.util.Iterator	iterator()           Get an iterator over all objects contained by this cube.
Cube	union(Cube other)           Create a cube containing the union of data in this cube and some other cube.

 

Methods inherited from interface java.util.Collection

add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, remove, removeAll, retainAll, size, toArray, toArray

 

Field Detail

EQUAL

public static final int EQUAL

operator that selects objects with attribute equal to a value

See Also:

Constant Field Values

---

LESS

public static final int LESS

operator that selects objects with attribute less than a value

See Also:

Constant Field Values

---

GREATER

public static final int GREATER

operator that selects objects with attribute greater than a value

See Also:

Constant Field Values

---

LESS_OR_EQUAL

public static final int LESS_OR_EQUAL

operator that selects objects with attribute less than or equal to a value

See Also:

Constant Field Values

---

GREATER_OR_EQUAL

public static final int GREATER_OR_EQUAL

operator that selects objects with attribute greater than equal to a value

See Also:

Constant Field Values

---

LAST_OPERAND

public static final int LAST_OPERAND

See Also:

Constant Field Values

Method Detail

constrain

public Cube constrain(Filter filter)

Creates a new cube containing some subset of the contents of this cube. The constrain(filter) method provides a way to generate subsets of the data contained in the cube. The subset generated is the set of objects for which filter.test(object) returns true. Users are therefore free to generate their own custom filter objects. However, the alternative constrain(attribute, operator, operand) method can be significantly optimised by the cube implementation. The alternative method should therefore be used whenever possible..

---

constrain

public Cube constrain(java.lang.String attribute,
                      int operator,
                      java.lang.Object operand)

Creates a new cube containing some subset of the contents of this cube. The constrain(attribute, operator, operand) method provides a way to generate standardised subsets of the data contained in the cube. The subset is formed by comparing the named attribute in all contained obects with the given operand. The comparison method is defined by operator, which should be one of the symbolic constants defined above: LESS, GREATER, EQUAL, LESS_OR_EQUAL, GREATER_OR_EQUAL

---

getSum

public double getSum(java.lang.String attribute)

Gets the sum over all contained objects of some attributes. This method is should be equivalent to summing: ((Number)getAttribute(attribute, object)).doubleValue() for all values returned by the Cube's iterator. However, certain cube implementations may cache or otherwise optimise the getSum() operation.

---

getMin

public java.lang.Object getMin(java.lang.String attribute)

Get the minimum value over all contained objects of some attribute. Cube implementations will generally have their own way to specify the comparison operation used to create this minimum.

---

getMax

public java.lang.Object getMax(java.lang.String attribute)

Get the maximum value over all contained objects of some attribute. Cube implementations will generally have their own way to specify the comparison operation used to create this minimum.

---

getAttribute

public java.lang.Object getAttribute(java.lang.String attribute,
                                     java.lang.Object object)

Get the value of an individual attribute of an object contained by this cube.

---

iterator

public java.util.Iterator iterator()

Get an iterator over all objects contained by this cube.

Specified by:

iterator in interface java.util.Collection

---

getAttributeSet

public java.util.SortedSet getAttributeSet(java.lang.String attribute)

Get a set of all the values of a given attribute across all contained objects.

---

groupBy

public java.util.Iterator groupBy(java.lang.String attribute)

Group data by a given attribute. Returns an iterator of a collection of Cubes. Each cube will contain only elements with the same value of the given attribute.

---

addAll

public void addAll(Cube cube)

Add all the data items in the given Cube to this cube. OPTIONAL OPERATION Adds many objects to this cube

---

getDescriptor

public CubeDescriptor getDescriptor()

Get metadata describing this cube.

---

union

public Cube union(Cube other)

Create a cube containing the union of data in this cube and some other cube.

---

Overview  Package   Class  Use  Deprecated  Index
Home >> All >> org >> jdaemon >> [ era overview ]	PREV CLASS  NEXT CLASS
SUMMARY:  JAVADOC |  SOURCE |  DOWNLOAD | NESTED | FIELD | CONSTR | METHOD	DETAIL: FIELD | CONSTR | METHOD

---