Class ForwardingMap<K extends @Nullable Object,V extends @Nullable Object>

java.lang.Object
com.google.common.collect.ForwardingObject
com.google.common.collect.ForwardingMap<K,V>
All Implemented Interfaces:
Map<K,V>
Direct Known Subclasses:
EnumBiMap, EnumHashBiMap, ForwardingConcurrentMap, ForwardingNavigableMap.StandardDescendingMap, ForwardingSortedMap, ImmutableClassToInstanceMap, ImmutableTypeToInstanceMap, MutableClassToInstanceMap, MutableTypeToInstanceMap
@GwtCompatible public abstract class ForwardingMap<K extends @Nullable Object,V extends @Nullable Object> extends ForwardingObject implements Map<K,V>
A map which forwards all its method calls to another map. Subclasses should override one or more methods to modify the behavior of the backing map as desired per the decorator pattern.

Warning: The methods of ForwardingMap forward indiscriminately to the methods of the delegate. For example, overriding put(K, V) alone will not change the behavior of putAll(java.util.Map<? extends K, ? extends V>), which can lead to unexpected behavior. In this case, you should override putAll as well, either providing your own implementation, or delegating to the provided standardPutAll method.

default method warning: This class does not forward calls to default methods. Instead, it inherits their default implementations. When those implementations invoke methods, they invoke methods on the ForwardingMap.

Each of the standard methods, where appropriate, use Objects.equal(java.lang.Object, java.lang.Object) to test equality for both keys and values. This may not be the desired behavior for map implementations that use non-standard notions of key equality, such as a SortedMap whose comparator is not consistent with equals.

The standard methods and the collection views they return are not guaranteed to be thread-safe, even when all of the methods that they depend on are thread-safe.

Since:
2.0
Author:
Kevin Bourrillion, Jared Levy, Louis Wasserman