public class

SynchronizedBag

extends SynchronizedCollection
implements Bag
java.lang.Object
   ↳ org.apache.commons.collections.collection.SynchronizedCollection
     ↳ org.apache.commons.collections.bag.SynchronizedBag
Known Direct Subclasses

Class Overview

Decorates another Bag to synchronize its behaviour for a multi-threaded environment.

Methods are synchronized, then forwarded to the decorated bag. Iterators must be separately synchronized around the loop.

This class is Serializable from Commons Collections 3.1.

Summary

[Expand]
Inherited Fields
From class org.apache.commons.collections.collection.SynchronizedCollection
Protected Constructors
SynchronizedBag(Bag bag)
Constructor that wraps (not copies).
SynchronizedBag(Bag bag, Object lock)
Constructor that wraps (not copies).
Public Methods
boolean add(Object object, int count)
Adds nCopies copies of the specified object to the Bag.
static Bag decorate(Bag bag)
Factory method to create a synchronized bag.
int getCount(Object object)
Returns the number of occurrences (cardinality) of the given object currently in the bag.
boolean remove(Object object, int count)
Removes nCopies copies of the specified object from the Bag.
Set uniqueSet()
Returns a Set of unique elements in the Bag.
Protected Methods
Bag getBag()
Gets the bag being decorated.
[Expand]
Inherited Methods
From class org.apache.commons.collections.collection.SynchronizedCollection
From class java.lang.Object
From interface java.lang.Iterable
From interface java.util.Collection
From interface org.apache.commons.collections.Bag

Protected Constructors

protected SynchronizedBag (Bag bag)

Constructor that wraps (not copies).

Parameters
bag the bag to decorate, must not be null
Throws
IllegalArgumentException if bag is null

protected SynchronizedBag (Bag bag, Object lock)

Constructor that wraps (not copies).

Parameters
bag the bag to decorate, must not be null
lock the lock to use, must not be null
Throws
IllegalArgumentException if bag is null

Public Methods

public boolean add (Object object, int count)

Adds nCopies copies of the specified object to the Bag.

If the object is already in the uniqueSet() then increment its count as reported by getCount(Object). Otherwise add it to the uniqueSet() and report its count as nCopies.

Parameters
object the object to add
count the number of copies to add
Returns
  • true if the object was not already in the uniqueSet

public static Bag decorate (Bag bag)

Factory method to create a synchronized bag.

Parameters
bag the bag to decorate, must not be null
Returns
  • a new synchronized Bag
Throws
IllegalArgumentException if bag is null

public int getCount (Object object)

Returns the number of occurrences (cardinality) of the given object currently in the bag. If the object does not exist in the bag, return 0.

Parameters
object the object to search for
Returns
  • the number of occurrences of the object, zero if not found

public boolean remove (Object object, int count)

Removes nCopies copies of the specified object from the Bag.

If the number of copies to remove is greater than the actual number of copies in the Bag, no error is thrown.

Parameters
object the object to remove
count the number of copies to remove
Returns
  • true if this call changed the collection

public Set uniqueSet ()

Returns a Set of unique elements in the Bag.

Uniqueness constraints are the same as those in Set.

Returns
  • the Set of unique Bag elements

Protected Methods

protected Bag getBag ()

Gets the bag being decorated.

Returns
  • the decorated bag