@GwtCompatible(serializable=true, emulated=true) public abstract class ImmutableMap<K,V> extends java.lang.Object implements java.util.Map<K,V>, java.io.Serializable
Map
with reliable user-specified iteration
order. Does not permit null keys or values.
Unlike Collections.unmodifiableMap(java.util.Map<? extends K, ? extends V>)
, which is a view of a
separate map which can still change, an instance of ImmutableMap
contains its own data and will never change. ImmutableMap
is
convenient for public static final
maps ("constant maps") and also
lets you easily make a "defensive copy" of a map provided to your class by a
caller.
Performance notes: unlike HashMap
, ImmutableMap
is
not optimized for element types that have slow Object.equals(java.lang.Object)
or
Object.hashCode()
implementations. You can get better performance by
having your element type cache its own hash codes, and by making use of the
cached values to short-circuit a slow equals
algorithm.
See the Guava User Guide article on immutable collections.
Modifier and Type | Class and Description |
---|---|
static class |
ImmutableMap.Builder<K,V>
A builder for creating immutable map instances, especially
public
static final maps ("constant maps"). |
private static class |
ImmutableMap.MapViewOfValuesAsSingletonSets<K,V> |
(package private) static class |
ImmutableMap.SerializedForm
Serialized type for all ImmutableMap instances.
|
Modifier and Type | Field and Description |
---|---|
private static java.util.Map.Entry<?,?>[] |
EMPTY_ENTRY_ARRAY |
private ImmutableSet<java.util.Map.Entry<K,V>> |
entrySet |
private ImmutableSet<K> |
keySet |
private ImmutableSetMultimap<K,V> |
multimapView |
private ImmutableCollection<V> |
values |
Constructor and Description |
---|
ImmutableMap() |
Modifier and Type | Method and Description |
---|---|
ImmutableSetMultimap<K,V> |
asMultimap()
Returns a multimap view of the map.
|
static <K,V> ImmutableMap.Builder<K,V> |
builder()
Returns a new builder.
|
(package private) static void |
checkNoConflict(boolean safe,
java.lang.String conflictDescription,
java.util.Map.Entry<?,?> entry1,
java.util.Map.Entry<?,?> entry2) |
void |
clear()
Deprecated.
Unsupported operation.
|
boolean |
containsKey(java.lang.Object key) |
boolean |
containsValue(java.lang.Object value) |
static <K,V> ImmutableMap<K,V> |
copyOf(java.util.Map<? extends K,? extends V> map)
Returns an immutable map containing the same entries as
map . |
private static <K extends java.lang.Enum<K>,V> |
copyOfEnumMap(java.util.Map<K,? extends V> original) |
private static <K,V> ImmutableMap<K,V> |
copyOfEnumMapUnsafe(java.util.Map<? extends K,? extends V> map) |
(package private) abstract ImmutableSet<java.util.Map.Entry<K,V>> |
createEntrySet() |
(package private) ImmutableSet<K> |
createKeySet() |
private ImmutableSetMultimap<K,V> |
createMultimapView() |
(package private) static <K,V> ImmutableMapEntry.TerminalEntry<K,V> |
entryOf(K key,
V value)
Verifies that
key and value are non-null, and returns a new
immutable entry with those values. |
ImmutableSet<java.util.Map.Entry<K,V>> |
entrySet()
Returns an immutable set of the mappings in this map.
|
boolean |
equals(java.lang.Object object) |
abstract V |
get(java.lang.Object key) |
int |
hashCode() |
boolean |
isEmpty() |
(package private) abstract boolean |
isPartialView() |
ImmutableSet<K> |
keySet()
Returns an immutable set of the keys in this map.
|
static <K,V> ImmutableMap<K,V> |
of()
Returns the empty map.
|
static <K,V> ImmutableMap<K,V> |
of(K k1,
V v1)
Returns an immutable map containing a single entry.
|
static <K,V> ImmutableMap<K,V> |
of(K k1,
V v1,
K k2,
V v2)
Returns an immutable map containing the given entries, in order.
|
static <K,V> ImmutableMap<K,V> |
of(K k1,
V v1,
K k2,
V v2,
K k3,
V v3)
Returns an immutable map containing the given entries, in order.
|
static <K,V> ImmutableMap<K,V> |
of(K k1,
V v1,
K k2,
V v2,
K k3,
V v3,
K k4,
V v4)
Returns an immutable map containing the given entries, in order.
|
static <K,V> ImmutableMap<K,V> |
of(K k1,
V v1,
K k2,
V v2,
K k3,
V v3,
K k4,
V v4,
K k5,
V v5)
Returns an immutable map containing the given entries, in order.
|
V |
put(K k,
V v)
Deprecated.
Unsupported operation.
|
void |
putAll(java.util.Map<? extends K,? extends V> map)
Deprecated.
Unsupported operation.
|
V |
remove(java.lang.Object o)
Deprecated.
Unsupported operation.
|
java.lang.String |
toString() |
ImmutableCollection<V> |
values()
Returns an immutable collection of the values in this map.
|
private ImmutableMap<K,ImmutableSet<V>> |
viewMapValuesAsSingletonSets() |
(package private) java.lang.Object |
writeReplace() |
private static final java.util.Map.Entry<?,?>[] EMPTY_ENTRY_ARRAY
private transient ImmutableSet<java.util.Map.Entry<K,V>> entrySet
private transient ImmutableSet<K> keySet
private transient ImmutableCollection<V> values
private transient ImmutableSetMultimap<K,V> multimapView
public static <K,V> ImmutableMap<K,V> of()
Collections.emptyMap()
, and is preferable mainly for consistency
and maintainability of your code.public static <K,V> ImmutableMap<K,V> of(K k1, V v1)
Collections.singletonMap(K, V)
but will not accept
a null key or value. It is preferable mainly for consistency and
maintainability of your code.public static <K,V> ImmutableMap<K,V> of(K k1, V v1, K k2, V v2)
java.lang.IllegalArgumentException
- if duplicate keys are providedpublic static <K,V> ImmutableMap<K,V> of(K k1, V v1, K k2, V v2, K k3, V v3)
java.lang.IllegalArgumentException
- if duplicate keys are providedpublic static <K,V> ImmutableMap<K,V> of(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4)
java.lang.IllegalArgumentException
- if duplicate keys are providedpublic static <K,V> ImmutableMap<K,V> of(K k1, V v1, K k2, V v2, K k3, V v3, K k4, V v4, K k5, V v5)
java.lang.IllegalArgumentException
- if duplicate keys are providedstatic <K,V> ImmutableMapEntry.TerminalEntry<K,V> entryOf(K key, V value)
key
and value
are non-null, and returns a new
immutable entry with those values.
A call to Map.Entry#setValue
on the returned entry will always
throw UnsupportedOperationException
.
public static <K,V> ImmutableMap.Builder<K,V> builder()
ImmutableMap.Builder
constructor.static void checkNoConflict(boolean safe, java.lang.String conflictDescription, java.util.Map.Entry<?,?> entry1, java.util.Map.Entry<?,?> entry2)
public static <K,V> ImmutableMap<K,V> copyOf(java.util.Map<? extends K,? extends V> map)
map
. If
map
somehow contains entries with duplicate keys (for example, if
it is a SortedMap
whose comparator is not consistent with
equals), the results of this method are undefined.
Despite the method name, this method attempts to avoid actually copying the data when it is safe to do so. The exact circumstances under which a copy will or will not be performed are undocumented and subject to change.
java.lang.NullPointerException
- if any key or value in map
is nullprivate static <K,V> ImmutableMap<K,V> copyOfEnumMapUnsafe(java.util.Map<? extends K,? extends V> map)
private static <K extends java.lang.Enum<K>,V> ImmutableMap<K,V> copyOfEnumMap(java.util.Map<K,? extends V> original)
@Deprecated public final V put(K k, V v)
@Deprecated public final V remove(java.lang.Object o)
@Deprecated public final void putAll(java.util.Map<? extends K,? extends V> map)
@Deprecated public final void clear()
public boolean containsKey(@Nullable java.lang.Object key)
public boolean containsValue(@Nullable java.lang.Object value)
public abstract V get(@Nullable java.lang.Object key)
public ImmutableSet<java.util.Map.Entry<K,V>> entrySet()
abstract ImmutableSet<java.util.Map.Entry<K,V>> createEntrySet()
public ImmutableSet<K> keySet()
ImmutableSet<K> createKeySet()
public ImmutableCollection<V> values()
@Beta public ImmutableSetMultimap<K,V> asMultimap()
private ImmutableSetMultimap<K,V> createMultimapView()
private ImmutableMap<K,ImmutableSet<V>> viewMapValuesAsSingletonSets()
public boolean equals(@Nullable java.lang.Object object)
abstract boolean isPartialView()
public int hashCode()
public java.lang.String toString()
toString
in class java.lang.Object
java.lang.Object writeReplace()