Package org.opendaylight.yangtools.util

Class ImmutableMapTemplate<K>

java.lang.Object

org.opendaylight.yangtools.util.ImmutableMapTemplate<K>

Type Parameters:

K - the type of keys maintained by this template

All Implemented Interfaces:

Immutable, MutationBehaviour<Immutable>

Direct Known Subclasses:

ImmutableOffsetMapTemplate, SharedSingletonMapTemplate

@Beta
public abstract class ImmutableMapTemplate<K>
extends Object
implements Immutable

Template for instantiating UnmodifiableMapPhase instances with a fixed set of keys. The template can then be used as a factory for instances via using instantiateTransformed(Map, BiFunction) or, more efficiently, using instantiateWithValues(Object[]) where the argument array has values ordered corresponding to the key order defined by keySet().

If the keySet is static known to contain only a single key, consider using SharedSingletonMapTemplate. If it is statically known to contain multiple keys, consider using ImmutableOffsetMapTemplate.

Method Summary

Modifier and Type	Method	Description
abstract <T,V> @NonNull UnmodifiableMapPhase<K,V>	instantiateTransformed(Map<K,T> fromMap, BiFunction<K,T,V> keyValueTransformer)	Instantiate an immutable map by applying specified transformer to values of fromMap.
abstract <V> @NonNull UnmodifiableMapPhase<K,V>	instantiateWithValues(V... values)	Instantiate an immutable map by filling values from provided array.
abstract Set<K>	keySet()	Returns the set of keys expected by this template, in the iteration order Maps resulting from instantiation will have.
static <K> @NonNull ImmutableMapTemplate<K>	ordered(Collection<K> keys)	Create a template which produces Maps with specified keys, with iteration order matching the iteration order of keys.
static <K> @NonNull ImmutableMapTemplate<K>	unordered(Collection<K> keys)	Create a template which produces Maps with specified keys, with unconstrained iteration order.

Methods inherited from class java.lang.Object

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

Method Detail

ordered

public static <K> @NonNull ImmutableMapTemplate<K> ordered(Collection<K> keys)

Create a template which produces Maps with specified keys, with iteration order matching the iteration order of keys. keySet() will return these keys in exactly the same order. The resulting map will retain insertion order through UnmodifiableMapPhase.toModifiableMap() transformations.

Type Parameters:

K - the type of keys maintained by resulting template

Parameters:

keys - Keys in requested iteration order.

Returns:

A template object.

Throws:

NullPointerException - if keys or any of its elements is null

IllegalArgumentException - if keys is empty

unordered

public static <K> @NonNull ImmutableMapTemplate<K> unordered(Collection<K> keys)

Create a template which produces Maps with specified keys, with unconstrained iteration order. Produced maps will have the iteration order matching the order returned by keySet(). The resulting map will NOT retain ordering through UnmodifiableMapPhase.toModifiableMap() transformations.

Type Parameters:

K - the type of keys maintained by resulting template

Parameters:

keys - Keys in any iteration order.

Returns:

A template object.

Throws:

NullPointerException - if keys or any of its elements is null

IllegalArgumentException - if keys is empty

instantiateTransformed

public abstract <T,V> @NonNull UnmodifiableMapPhase<K,V> instantiateTransformed(Map<K,T> fromMap,
                                                                                            BiFunction<K,T,V> keyValueTransformer)

Instantiate an immutable map by applying specified transformer to values of fromMap.

Type Parameters:

T - the type of input values

V - the type of mapped values

Parameters:

fromMap - Input map

keyValueTransformer - Transformation to apply to values

Returns:

An immutable map

Throws:

NullPointerException - if any of the arguments is null or if the transformer produces a null value

IllegalArgumentException - if fromMap#keySet() does not match this template's keys

instantiateWithValues

public abstract <V> @NonNull UnmodifiableMapPhase<K,V> instantiateWithValues(V... values)

Instantiate an immutable map by filling values from provided array. The array MUST be ordered to match key order as returned by keySet().

Type Parameters:

V - the type of mapped values

Parameters:

values - Values to use

Returns:

An immutable map

Throws:

NullPointerException - if values or any of its elements is null

IllegalArgumentException - if values.length does not match the number of keys in this template

keySet

public abstract Set<K> keySet()

Returns the set of keys expected by this template, in the iteration order Maps resulting from instantiation will have.

Returns:

This template's key set

See Also:

Map.keySet()