# Class PredicatedList<E>

java.lang.Object
org.apache.commons.collections4.collection.AbstractCollectionDecorator<E>
org.apache.commons.collections4.collection.PredicatedCollection<E>
org.apache.commons.collections4.list.PredicatedList<E>

Type Parameters:
  `E` - the type of the elements in the list.

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

public class PredicatedList<E> extends PredicatedCollection<E> implements List<E>
Decorates another `List` to validate that all additions match a specified predicate.

This list exists to provide validation for the decorated list. It is normally created to decorate an empty list. If an object cannot be added to the list, an IllegalArgumentException is thrown.

One usage would be to ensure that no null entries are added to the list.

     List<String> list =
       PredicatedList.predicatedList(new ArrayList<String>(), PredicateUtils.notNullPredicate());

This class is Serializable from Commons Collections 3.1.

Since:
  3.0
See Also:
  - Serialized Form

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `protected class`
  `PredicatedList.PredicatedListIterator`
  Inner class Iterator for the PredicatedList

  ### Nested classes/interfaces inherited from class org.apache.commons.collections4.collection.PredicatedCollection

  `PredicatedCollection.Builder<E>`

- ## Field Summary

  ### Fields inherited from class org.apache.commons.collections4.collection.PredicatedCollection

  `predicate`

- ## Constructor Summary

  Constructors
  Modifier
  Constructor
  Description
  `protected`
  `PredicatedList(List<E> list, Predicate<? super E> predicate)`
  Constructor that wraps (not copies).

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `add(int index, E object)`
  `boolean`
  `addAll(int index, Collection<? extends E> coll)`
  `protected List<E>`
  `decorated()`
  Gets the list being decorated.
  `boolean`
  `equals(Object object)`
  `E`
  `get(int index)`
  `int`
  `hashCode()`
  `int`
  `indexOf(Object object)`
  `int`
  `lastIndexOf(Object object)`
  `ListIterator<E>`
  `listIterator()`
  `ListIterator<E>`
  `listIterator(int i)`
  `static <T> PredicatedList<T>`
  `predicatedList(List<T> list, Predicate<? super T> predicate)`
  Factory method to create a predicated (validating) list.
  `E`
  `remove(int index)`
  `E`
  `set(int index, E object)`
  `List<E>`
  `subList(int fromIndex, int toIndex)`

  ### Methods inherited from class org.apache.commons.collections4.collection.PredicatedCollection

  `add, addAll, builder, notNullBuilder, predicatedCollection, validate`

  ### Methods inherited from class org.apache.commons.collections4.collection.AbstractCollectionDecorator

  `clear, contains, containsAll, isEmpty, iterator, remove, removeAll, removeIf, retainAll, setCollection, size, 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`

  ### Methods inherited from interface java.lang.Iterable

  `forEach`

  ### Methods inherited from interface java.util.List

  `add, addAll, clear, contains, containsAll, isEmpty, iterator, remove, removeAll, replaceAll, retainAll, size, sort, spliterator, toArray, toArray`

- ## Constructor Details

  - ### PredicatedList

    protected PredicatedList(List<E> list, Predicate<? super E> predicate)
    Constructor that wraps (not copies).

    If there are any elements already in the list being decorated, they are validated.

    Parameters:
      `list` - the list to decorate, must not be null
      `predicate` - the predicate to use for validation, must not be null
    Throws:
      `NullPointerException` - if list or predicate is null
      `IllegalArgumentException` - if the list contains invalid elements

- ## Method Details

  - ### predicatedList

    public static <T> PredicatedList<T> predicatedList(List<T> list, Predicate<? super T> predicate)
    Factory method to create a predicated (validating) list.

    If there are any elements already in the list being decorated, they are validated.

    Type Parameters:
      `T` - the type of the elements in the list
    Parameters:
      `list` - the list to decorate, must not be null
      `predicate` - the predicate to use for validation, must not be null
    Returns:
      a new predicated list
    Throws:
      `NullPointerException` - if list or predicate is null
      `IllegalArgumentException` - if the list contains invalid elements
    Since:
      4.0

  - ### add

    public void add(int index, E object)
    Specified by:
      `add` in interface `List<E>`

  - ### addAll

    public boolean addAll(int index, Collection<? extends E> coll)
    Specified by:
      `addAll` in interface `List<E>`

  - ### decorated

    protected List<E> decorated()
    Gets the list being decorated.
    Overrides:
      `decorated` in class `AbstractCollectionDecorator<E>`
    Returns:
      the decorated list

  - ### equals

    public boolean equals(Object object)
    Specified by:
      `equals` in interface `Collection<E>`
    Specified by:
      `equals` in interface `List<E>`
    Overrides:
      `equals` in class `Object`

  - ### get

    public E get(int index)
    Specified by:
      `get` in interface `List<E>`

  - ### hashCode

    public int hashCode()
    Specified by:
      `hashCode` in interface `Collection<E>`
    Specified by:
      `hashCode` in interface `List<E>`
    Overrides:
      `hashCode` in class `Object`

  - ### indexOf

    public int indexOf(Object object)
    Specified by:
      `indexOf` in interface `List<E>`

  - ### lastIndexOf

    public int lastIndexOf(Object object)
    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 i)
    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 object)
    Specified by:
      `set` in interface `List<E>`

  - ### subList

    public List<E> subList(int fromIndex, int toIndex)
    Specified by:
      `subList` in interface `List<E>`