com.neeve.ods

Interface IStoreIndex<K,T extends IStoreObject>

Type Parameters:

K - Object field type that is used as index key.

T - Indexed object type. It is an instance of IStoreObject.

All Known Subinterfaces:

IStoreNonUniqueIndex<K,T>, IStoreUniqueIndex<K,T>

public interface IStoreIndex<K,T extends IStoreObject>

Index on ODS store. This is the basis of querying facilities in ODS.

Method Summary

Modifier and Type	Method and Description
Iterable<T>	allValues(boolean ascending) Retrieve all object from the index.
boolean	containsKey(K key) Determine whether the index contains the specified key.
<KEY extends Comparable<KEY>> Iterable<T>	get(KEY start, KEY end, boolean includeStart, boolean includeEnd) Gets the an Iterable of the entries in the given range
int	getCardinality() The number of entries in the IStoreIndex.
String	getFieldCanonicalName() Returns canonical name of the field that is indexed by this index
K	getHighKey() The highest key in the IStoreIndex, provided that this index is against a Comparable field.
int	getKeyCardinality() The number of keys in the IStoreIndex.
K	getLowKey() The lowest key in the IStoreIndex, provided that this index is against a Comparable field.
String	getName() Gets the name of the index.
boolean	isUnique() Checks if this index is unique index.

Method Detail

getName

String getName()

Gets the name of the index.

Returns:

The index name or null if index was not created with a name.

getKeyCardinality

int getKeyCardinality()

The number of keys in the IStoreIndex.

Returns:

The number of keys in the IStoreIndex.

getCardinality

int getCardinality()

The number of entries in the IStoreIndex. If this index is unique, this cardinality will be same as key cardinality.

Returns:

The number of entries in the IStoreIndex.

getLowKey

K getLowKey()

The lowest key in the IStoreIndex, provided that this index is against a Comparable field. Null otherwise.

Returns:

The lowest key in the IdxIndex

getHighKey

K getHighKey()

The highest key in the IStoreIndex, provided that this index is against a Comparable field. Null otherwise.

Returns:

The highest key in the IdxIndex

containsKey

boolean containsKey(K key)

Determine whether the index contains the specified key.

Parameters:

key - The key to look for.

Returns:

Whether or not the index contains the key.

allValues

Iterable<T> allValues(boolean ascending)

Retrieve all object from the index.

Parameters:

ascending - Indicates whether the index is read in ascending key order or descending key order.

Returns:

An Iterable of all of the entries indexed.

get

<KEY extends Comparable<KEY>> Iterable<T> get(KEY start,
                                              KEY end,
                                              boolean includeStart,
                                              boolean includeEnd)

Gets the an Iterable of the entries in the given range

Parameters:

start - Start of range. If null, range is not bound from below.

end - End of range. If null, range is not bound from above.

includeStart - Set true to include start key into results. Has no effect if start is set to null.

includeEnd - Set true to include end key into results. Has no effect if end is set to null.

Returns:

An Iterable of the entries in the given range

isUnique

boolean isUnique()

Checks if this index is unique index.

Returns:

true if this is unique index, else false.

getFieldCanonicalName

String getFieldCanonicalName()

Returns canonical name of the field that is indexed by this index

Returns:

Field canonical name