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

java.lang.Object
  extended by com.google.common.collect.ForwardingObject
      extended by com.google.common.collect.ForwardingCollection<E>
          extended by 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), 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() and get(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() and get(int). If you override either 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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