## com.google.common.collect
Class ForwardingList<E>

    java.lang.Object
      com.google.common.collect.ForwardingObject
          com.google.common.collect.ForwardingCollection<E>
              com.google.common.collect.ForwardingList<E>

All Implemented Interfaces:
  Iterable<E>, Collection<E>, List<E>

    @GwtCompatible
    public abstract class ForwardingList<E>

extends ForwardingCollection<E>
implements List<E>

A list which forwards all its method calls to another list. Subclasses should override one or more methods to modify the behavior of the backing list as desired per the decorator pattern.

This class does not implement `RandomAccess`. If the delegate supports random access, the `ForwardingList` subclass should implement the `RandomAccess` interface.

Warning: The methods of `ForwardingList` forward indiscriminately to the methods of the delegate. For example, overriding `add(int, E)` alone will not change the behavior of `addAll(int, java.util.Collection<? extends E>)`, which can lead to unexpected behavior. In this case, you should override `addAll` as well, either providing your own implementation, or delegating to the provided `standardAddAll` method.

The `standard` methods and any 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 (imported from Google Collections Library)
Author:
  Mike Bostock, Louis Wasserman

Constructor Summary
`protected` `ForwardingList()` Constructor for use by subclasses.

Method Summary
`void` `add(int index, E element)`
`boolean` `addAll(int index, Collection<? extends E> elements)`
`protected abstract List<E>` `delegate()` Returns the backing delegate instance that methods are forwarded to.
`boolean` `equals(Object object)`
`E` `get(int index)`
`int` `hashCode()`
`int` `indexOf(Object element)`
`int` `lastIndexOf(Object element)`
`ListIterator<E>` `listIterator()`
`ListIterator<E>` `listIterator(int index)`
`E` `remove(int index)`
`E` `set(int index, E element)`
`protected boolean` `standardAdd(E element)` A sensible default implementation of `ForwardingCollection.add(Object)`, in terms of `add(int, Object)`.
`protected boolean` `standardAddAll(int index, Iterable<? extends E> elements)` A sensible default implementation of `addAll(int, Collection)`, in terms of the `add` method of `listIterator(int)`.
`protected boolean` `standardEquals(Object object)` A sensible definition of `equals(Object)` in terms of `ForwardingCollection.size()` and `ForwardingCollection.iterator()`.
`protected int` `standardHashCode()` A sensible definition of `hashCode()` in terms of `ForwardingCollection.iterator()`.
`protected int` `standardIndexOf(Object element)` A sensible default implementation of `indexOf(java.lang.Object)`, in terms of `listIterator()`.
`protected Iterator<E>` `standardIterator()` A sensible default implementation of `ForwardingCollection.iterator()`, in terms of `listIterator()`.
`protected int` `standardLastIndexOf(Object element)` A sensible default implementation of `lastIndexOf(java.lang.Object)`, in terms of `listIterator(int)`.
`protected ListIterator<E>` `standardListIterator()` A sensible default implementation of `listIterator()`, in terms of `listIterator(int)`.
`protected ListIterator<E>` `standardListIterator(int start)` A sensible default implementation of `listIterator(int)`, in terms of `ForwardingCollection.size()`, `get(int)`, `set(int, Object)`, `add(int, Object)`, and `remove(int)`.
`protected List<E>` `standardSubList(int fromIndex, int toIndex)` A sensible default implementation of `subList(int, int)`.
`List<E>` `subList(int fromIndex, int toIndex)`

Methods inherited from class com.google.common.collect.ForwardingCollection
`add, addAll, clear, contains, containsAll, isEmpty, iterator, remove, removeAll, retainAll, size, standardAddAll, standardClear, standardContains, standardContainsAll, standardIsEmpty, standardRemove, standardRemoveAll, standardRetainAll, standardToArray, standardToArray, standardToString, toArray, toArray`

Methods inherited from class com.google.common.collect.ForwardingObject
`toString`

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

Methods inherited from interface java.util.List
`add, addAll, clear, contains, containsAll, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray`

Constructor Detail

### ForwardingList

    protected ForwardingList()

  Constructor for use by subclasses.

Method Detail

### delegate

    protected abstract List<E> delegate()

  Description copied from class: `ForwardingObject`
  Returns the backing delegate instance that methods are forwarded to. Abstract subclasses generally override this method with an abstract method that has a more specific return type, such as `ForwardingSet.delegate()`. Concrete subclasses override this method to supply the instance being decorated.

  Specified by:
    `delegate` in class `ForwardingCollection<E>`

### add

    public void add(int index,
                    E element)

  Specified by:
    `add` in interface `List<E>`

### addAll

    public boolean addAll(int index,
                          Collection<? extends E> elements)

  Specified by:
    `addAll` in interface `List<E>`

### get

    public E get(int index)

  Specified by:
    `get` in interface `List<E>`

### indexOf

    public int indexOf(Object element)

  Specified by:
    `indexOf` in interface `List<E>`

### lastIndexOf

    public int lastIndexOf(Object element)

  Specified by:
    `lastIndexOf` in interface `List<E>`

### listIterator

    public ListIterator<E> listIterator()

  Specified by:
    `listIterator` in interface `List<E>`

### listIterator

    public ListIterator<E> listIterator(int index)

  Specified by:
    `listIterator` in interface `List<E>`

### remove

    public E remove(int index)

  Specified by:
    `remove` in interface `List<E>`

### set

    public E set(int index,
                 E element)

  Specified by:
    `set` in interface `List<E>`

### subList

    public List<E> subList(int fromIndex,
                           int toIndex)

  Specified by:
    `subList` in interface `List<E>`

### equals

    public boolean equals(@Nullable
                          Object object)

  Specified by:
    `equals` in interface `Collection<E>`
  Specified by:
    `equals` in interface `List<E>`
  Overrides:
    `equals` in class `Object`

### hashCode

    public int hashCode()

  Specified by:
    `hashCode` in interface `Collection<E>`
  Specified by:
    `hashCode` in interface `List<E>`
  Overrides:
    `hashCode` in class `Object`

### standardAdd

    @Beta
    protected boolean standardAdd(E element)

  A sensible default implementation of `ForwardingCollection.add(Object)`, in terms of `add(int, Object)`. If you override `add(int, Object)`, you may wish to override `ForwardingCollection.add(Object)` to forward to this implementation.

  Since:
    7.0

### standardAddAll

    @Beta
    protected boolean standardAddAll(int index,
                                          Iterable<? extends E> elements)

  A sensible default implementation of `addAll(int, Collection)`, in terms of the `add` method of `listIterator(int)`. If you override `listIterator(int)`, you may wish to override `addAll(int, Collection)` to forward to this implementation.

  Since:
    7.0

### standardIndexOf

    @Beta
    protected int standardIndexOf(@Nullable
                                       Object element)

  A sensible default implementation of `indexOf(java.lang.Object)`, in terms of `listIterator()`. If you override `listIterator()`, you may wish to override `indexOf(java.lang.Object)` to forward to this implementation.

  Since:
    7.0

### standardLastIndexOf

    @Beta
    protected int standardLastIndexOf(@Nullable
                                           Object element)

  A sensible default implementation of `lastIndexOf(java.lang.Object)`, in terms of `listIterator(int)`. If you override `listIterator(int)`, you may wish to override `lastIndexOf(java.lang.Object)` to forward to this implementation.

  Since:
    7.0

### standardIterator

    @Beta
    protected Iterator<E> standardIterator()

  A sensible default implementation of `ForwardingCollection.iterator()`, in terms of `listIterator()`. If you override `listIterator()`, you may wish to override `ForwardingCollection.iterator()` to forward to this implementation.

  Since:
    7.0

### standardListIterator

    @Beta
    protected ListIterator<E> standardListIterator()

  A sensible default implementation of `listIterator()`, in terms of `listIterator(int)`. If you override `listIterator(int)`, you may wish to override `listIterator()` to forward to this implementation.

  Since:
    7.0

### standardListIterator

    @Beta
    protected ListIterator<E> standardListIterator(int start)

  A sensible default implementation of `listIterator(int)`, in terms of `ForwardingCollection.size()`, `get(int)`, `set(int, Object)`, `add(int, Object)`, and `remove(int)`. If you override any of these methods, you may wish to override `listIterator(int)` to forward to this implementation.

  Since:
    7.0

### standardSubList

    @Beta
    protected List<E> standardSubList(int fromIndex,
                                           int toIndex)

  A sensible default implementation of `subList(int, int)`. If you override any other methods, you may wish to override `subList(int, int)` to forward to this implementation.

  Since:
    7.0

### standardEquals

    @Beta
    protected boolean standardEquals(@Nullable
                                          Object object)

  A sensible definition of `equals(Object)` in terms of `ForwardingCollection.size()` and `ForwardingCollection.iterator()`. If you override either of those methods, you may wish to override `equals(Object)` to forward to this implementation.

  Since:
    7.0

### standardHashCode

    @Beta
    protected int standardHashCode()

  A sensible definition of `hashCode()` in terms of `ForwardingCollection.iterator()`. If you override `ForwardingCollection.iterator()`, you may wish to override `hashCode()` to forward to this implementation.

  Since:
    7.0

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