org.openimaj.data.dataset

Class MapBackedDataset<KEY,DATASET extends Dataset<INSTANCE>,INSTANCE>

java.lang.Object

java.util.AbstractMap<KEY,DATASET>

org.openimaj.data.dataset.MapBackedDataset<KEY,DATASET,INSTANCE>

Type Parameters:

KEY - Type of dataset class key

DATASET - Type of sub-datasets.

INSTANCE - Type of objects in the dataset

All Implemented Interfaces:

Iterable<INSTANCE>, Map<KEY,DATASET>, Dataset<INSTANCE>, GroupedDataset<KEY,DATASET,INSTANCE>

Direct Known Subclasses:

ATandTDataset, ClusterEvalDataset, MusicSpeechDataset, TextFileDataset, WineDataset

public class MapBackedDataset<KEY,DATASET extends Dataset<INSTANCE>,INSTANCE>
extends AbstractMap<KEY,DATASET>
implements GroupedDataset<KEY,DATASET,INSTANCE>

A MapBackedDataset is a concrete implementation of a GroupedDataset backed by a Map.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	MapBackedDataset.IdentifiableBuilder<DATASET extends Dataset<INSTANCE> & Identifiable,INSTANCE> A builder for creating MapBackedDataset instances from Identifiable sub-datasets.

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<KEY,DATASET>	map

Constructor Summary

Constructors

Constructor and Description
MapBackedDataset() Construct an empty MapBackedDataset backed by a HashMap.
MapBackedDataset(Map<KEY,DATASET> map) Construct with the given map.

Method Summary

Modifier and Type	Method and Description
MapBackedDataset<KEY,DATASET,INSTANCE>	add(KEY key, DATASET dataset) Convenience method for populating a dataset by chaining method calls:
static <DATASET extends Dataset<INSTANCE> & Identifiable,INSTANCE> MapBackedDataset.IdentifiableBuilder<DATASET,INSTANCE>	builder() Returns a new builder.
Set<Map.Entry<KEY,DATASET>>	entrySet()
Set<KEY>	getGroups() Get the set of all defined group keys.
DATASET	getInstances(KEY key) Get sub-dataset corresponding to the given group key
Map<KEY,DATASET>	getMap() Get the underlying map.
INSTANCE	getRandomInstance()
INSTANCE	getRandomInstance(KEY key) Get a random instance from the sub-dataset corresponding to a specific group.
Iterator<INSTANCE>	iterator()
int	numInstances() Returns the number of instances in this dataset.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(Collection<DATASET> datasets) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(DATASET... datasets) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(DATASET d1) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(DATASET d1, DATASET d2) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(DATASET d1, DATASET d2, DATASET d3) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(DATASET d1, DATASET d2, DATASET d3, DATASET d4) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE>	of(DATASET d1, DATASET d2, DATASET d3, DATASET d4, DATASET d5) Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets.
DATASET	put(KEY key, DATASET value)
String	toString()

Methods inherited from class java.util.AbstractMap

clear, clone, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, putAll, remove, size, values

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface java.util.Map

clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Field Detail

map

protected Map<KEY,DATASET extends Dataset<INSTANCE>> map

Constructor Detail

MapBackedDataset

public MapBackedDataset()

Construct an empty MapBackedDataset backed by a HashMap.

MapBackedDataset

public MapBackedDataset(Map<KEY,DATASET> map)

Construct with the given map.

Parameters:

map - the map

Method Detail

getMap

public Map<KEY,DATASET> getMap()

Get the underlying map.

Returns:

the underlying map

getInstances

public DATASET getInstances(KEY key)

Description copied from interface: GroupedDataset

Get sub-dataset corresponding to the given group key

Specified by:

getInstances in interface GroupedDataset<KEY,DATASET extends Dataset<INSTANCE>,INSTANCE>

Parameters:

key - the key.

Returns:

the sub dataset, or null if the key was unknown

getGroups

public Set<KEY> getGroups()

Description copied from interface: GroupedDataset

Get the set of all defined group keys.

Specified by:

getGroups in interface GroupedDataset<KEY,DATASET extends Dataset<INSTANCE>,INSTANCE>

Returns:

the the set of all defined group keys.

getRandomInstance

public INSTANCE getRandomInstance(KEY key)

Description copied from interface: GroupedDataset

Get a random instance from the sub-dataset corresponding to a specific group.

Specified by:

getRandomInstance in interface GroupedDataset<KEY,DATASET extends Dataset<INSTANCE>,INSTANCE>

Parameters:

key - the group key

Returns:

a random item from the group.

getRandomInstance

public INSTANCE getRandomInstance()

Specified by:

getRandomInstance in interface Dataset<INSTANCE>

Returns:

a randomly selected instance from the dataset.

numInstances

public int numInstances()

Description copied from interface: Dataset

Returns the number of instances in this dataset.

Specified by:

numInstances in interface Dataset<INSTANCE>

Returns:

the number of instances in this list

iterator

public Iterator<INSTANCE> iterator()

Specified by:

iterator in interface Iterable<INSTANCE>

toString

public String toString()

Overrides:

toString in class AbstractMap<KEY,DATASET extends Dataset<INSTANCE>>

entrySet

public Set<Map.Entry<KEY,DATASET>> entrySet()

Specified by:

entrySet in interface Map<KEY,DATASET extends Dataset<INSTANCE>>

Specified by:

entrySet in class AbstractMap<KEY,DATASET extends Dataset<INSTANCE>>

put

public DATASET put(KEY key,
                   DATASET value)

Specified by:

put in interface Map<KEY,DATASET extends Dataset<INSTANCE>>

Overrides:

put in class AbstractMap<KEY,DATASET extends Dataset<INSTANCE>>

add

public MapBackedDataset<KEY,DATASET,INSTANCE> add(KEY key,
                                                  DATASET dataset)

Convenience method for populating a dataset by chaining method calls:

 final MapBackedDataset<String, ListDataset<String>, String> ds = new MapBackedDataset<String, ListDataset<String>, String>()
                .add("A", new ListBackedDataset<String>())
                .add("B", new ListBackedDataset<String>());
 

Parameters:

key - the key to insert

dataset - the value to insert

Returns:

this dataset

of

@SafeVarargs
public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(DATASET... datasets)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

datasets - the datasets representing the groups

Returns:

the newly constructed grouped dataset.

builder

public static <DATASET extends Dataset<INSTANCE> & Identifiable,INSTANCE> MapBackedDataset.IdentifiableBuilder<DATASET,INSTANCE> builder()

Returns a new builder. The generated builder is equivalent to the builder created by the IdentifiableBuilder#IdentifiableBuilder() constructor.

Returns:

a new builder.

of

public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(DATASET d1)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

d1 - first dataset

Returns:

the newly constructed grouped dataset.

of

public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(DATASET d1,
                                                                                                                       DATASET d2)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

d1 - first dataset

d2 - second dataset

Returns:

the newly constructed grouped dataset.

of

public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(DATASET d1,
                                                                                                                       DATASET d2,
                                                                                                                       DATASET d3)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

d1 - first dataset

d2 - second dataset

d3 - third dataset

Returns:

the newly constructed grouped dataset.

of

public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(DATASET d1,
                                                                                                                       DATASET d2,
                                                                                                                       DATASET d3,
                                                                                                                       DATASET d4)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

d1 - first dataset

d2 - second dataset

d3 - third dataset

d4 - forth dataset

Returns:

the newly constructed grouped dataset.

of

public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(DATASET d1,
                                                                                                                       DATASET d2,
                                                                                                                       DATASET d3,
                                                                                                                       DATASET d4,
                                                                                                                       DATASET d5)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

d1 - first dataset

d2 - second dataset

d3 - third dataset

d4 - forth dataset

d5 - fifth dataset

Returns:

the newly constructed grouped dataset.

of

public static <INSTANCE,DATASET extends Dataset<INSTANCE> & Identifiable> MapBackedDataset<String,DATASET,INSTANCE> of(Collection<DATASET> datasets)

Convenience method to construct a MapBackedDataset from a number of Identifiable sub-datasets. Each sub-dataset becomes a group, and the key is the identifier returned by Identifiable.getID().

Parameters:

datasets - the datasets representing the groups

Returns:

the newly constructed grouped dataset.