java.lang.Object
- java.util.AbstractCollection<E>
- - java.util.AbstractSet<E>
  - - com.google.common.collect.ForwardingMap.StandardKeySet

All Implemented Interfaces:

java.lang.Iterable<K>, java.util.Collection<K>, java.util.Set<K>

Enclosing class:

ForwardingMap<K extends @Nullable java.lang.Object,V extends @Nullable java.lang.Object>
```
protected class ForwardingMap.StandardKeySet
extends java.util.AbstractSet<E>
```
A sensible implementation of Map.keySet() in terms of the following methods: ForwardingMap.clear(), ForwardingMap.containsKey(java.lang.Object), ForwardingMap.isEmpty(), ForwardingMap.remove(java.lang.Object), ForwardingMap.size(), and the Set.iterator() method of ForwardingMap.entrySet(). In many cases, you may wish to override ForwardingMap.keySet() to forward to this implementation or a subclass thereof.

Since:

10.0

Constructor Summary

Constructors
Constructor Description

StandardKeySet()
Constructor for use by subclasses.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`clear()`
`boolean`	`contains(java.lang.Object o)`
`boolean`	`isEmpty()`
`java.util.Iterator<K>`	`iterator()`
`boolean`	`remove(java.lang.Object o)`
`boolean`	`removeAll(java.util.Collection<?> c)`
`boolean`	`retainAll(java.util.Collection<?> c)`
`int`	`size()`

Methods inherited from class java.util.AbstractSet
equals, hashCode

Methods inherited from class java.util.AbstractCollection
add, addAll, containsAll, toArray, toArray, toString

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection
parallelStream, removeIf, stream, toArray

Methods inherited from interface java.lang.Iterable
forEach

Methods inherited from interface java.util.Set
add, addAll, containsAll, spliterator, toArray, toArray

- Constructor Detail
  - StandardKeySet
```
public StandardKeySet()
```
    Constructor for use by subclasses.
- Method Detail
  - iterator
```
public java.util.Iterator<K> iterator()
```
    Specified by:
    
    iterator in interface java.util.Collection<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    iterator in interface java.lang.Iterable<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    iterator in interface java.util.Set<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    iterator in class java.util.AbstractCollection<K extends @Nullable java.lang.Object>
  - size
```
public int size()
```
    Specified by:
    
    size in interface java.util.Collection<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    size in interface java.util.Set<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    size in class java.util.AbstractCollection<K extends @Nullable java.lang.Object>
  - isEmpty
```
public boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface java.util.Collection<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    isEmpty in interface java.util.Set<K extends @Nullable java.lang.Object>
    
    Overrides:
    
    isEmpty in class java.util.AbstractCollection<K extends @Nullable java.lang.Object>
  - contains
```
public boolean contains(@CheckForNull
                        java.lang.Object o)
```
    Specified by:
    
    contains in interface java.util.Collection<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    contains in interface java.util.Set<K extends @Nullable java.lang.Object>
    
    Overrides:
    
    contains in class java.util.AbstractCollection<K extends @Nullable java.lang.Object>
  - remove
```
public boolean remove(@CheckForNull
                      java.lang.Object o)
```
    Specified by:
    
    remove in interface java.util.Collection<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    remove in interface java.util.Set<K extends @Nullable java.lang.Object>
    
    Overrides:
    
    remove in class java.util.AbstractCollection<K extends @Nullable java.lang.Object>
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface java.util.Collection<K extends @Nullable java.lang.Object>
    
    Specified by:
    
    clear in interface java.util.Set<K extends @Nullable java.lang.Object>
    
    Overrides:
    
    clear in class java.util.AbstractCollection<K extends @Nullable java.lang.Object>
  - removeAll
```
public boolean removeAll(java.util.Collection<?> c)
```
    Specified by:
    
    removeAll in interface java.util.Collection<E extends @Nullable java.lang.Object>
    
    Specified by:
    
    removeAll in interface java.util.Set<E extends @Nullable java.lang.Object>
    
    Overrides:
    
    removeAll in class java.util.AbstractSet<E extends @Nullable java.lang.Object>
  - retainAll
```
public boolean retainAll(java.util.Collection<?> c)
```
    Specified by:
    
    retainAll in interface java.util.Collection<E extends @Nullable java.lang.Object>
    
    Specified by:
    
    retainAll in interface java.util.Set<E extends @Nullable java.lang.Object>
    
    Overrides:
    
    retainAll in class java.util.AbstractCollection<E extends @Nullable java.lang.Object>

Class ForwardingMap.StandardKeySet

Constructor Summary

Method Summary

Methods inherited from class java.util.AbstractSet

Methods inherited from class java.util.AbstractCollection

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.Collection

Methods inherited from interface java.lang.Iterable

Methods inherited from interface java.util.Set

Constructor Detail

StandardKeySet

Method Detail

iterator

size

isEmpty

contains

remove

clear

removeAll

retainAll