Class Overview
LinkedHashSet is a variant of HashSet. Its entries are kept in a
 doubly-linked list. The iteration order is the order in which entries were
 inserted.
 
 Null elements are allowed, and all the optional Set operations are supported.
 
 Like HashSet, LinkedHashSet is not thread safe, so access by multiple threads
 must be synchronized by an external mechanism such as
 synchronizedSet(Set).
 
Summary
| Public Constructors | 
	 
    
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        LinkedHashSet()
        
         Constructs a new empty instance of LinkedHashSet. 
  
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        LinkedHashSet(int capacity)
        
         Constructs a new instance of LinkedHashSet with the specified
 capacity. 
  
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        LinkedHashSet(int capacity, float loadFactor)
        
         Constructs a new instance of LinkedHashSet with the specified
 capacity and load factor. 
  
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         | 
        
        LinkedHashSet(Collection<? extends E> collection)
        
         Constructs a new instance of LinkedHashSet containing the unique
 elements in the specified collection. 
  
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  [Expand]
   Inherited Methods  | 
   
From class
  java.util.HashSet
  
   
  
    
    
	 
    
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            boolean
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        add(E object)
        
         Adds the specified object to this HashSet if not already present. 
  
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            void
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        clear()
        
         Removes all elements from this HashSet, leaving it empty. 
  
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            Object
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        clone()
        
         Returns a new HashSet with the same elements and size as this
 HashSet. 
  
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            boolean
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        contains(Object object)
        
         Searches this HashSet for the specified object. 
  
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            boolean
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        isEmpty()
        
         Returns true if this HashSet has no elements, false otherwise. 
  
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            Iterator<E>
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        iterator()
        
         Returns an Iterator on the elements of this HashSet. 
  
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            boolean
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        remove(Object object)
        
         Removes the specified object from this HashSet. 
  
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            int
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        size()
        
         Returns the number of elements in this HashSet. 
  
   |  
 
   
 
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From class
  java.util.AbstractSet
  
   
  
    
    
	 
    
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            boolean
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        equals(Object object)
        
         Compares the specified object to this Set and returns true if they are
 equal. 
  
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            int
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        hashCode()
        
         Returns the hash code for this set. 
  
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            boolean
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        removeAll(Collection<?> collection)
        
         Removes all occurrences in this collection which are contained in the
 specified collection. 
  
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From class
  java.util.AbstractCollection
  
   
  
    
    
	 
    
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            boolean
         | 
        
        add(E object)
        
         Attempts to add object to the contents of this
 Collection (optional). 
  
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            boolean
         | 
        
        addAll(Collection<? extends E> collection)
        
         Attempts to add all of the objects contained in collection
 to the contents of this Collection (optional). 
  
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        | 
            
            
            
            
            
            void
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        clear()
        
         Removes all elements from this Collection, leaving it empty (optional). 
  
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            boolean
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        contains(Object object)
        
         Tests whether this Collection contains the specified object. 
  
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            boolean
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        containsAll(Collection<?> collection)
        
         Tests whether this Collection contains all objects contained in the
 specified Collection. 
  
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            boolean
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        isEmpty()
        
         Returns if this Collection contains no elements. 
  
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            abstract
            
            
            
            
            Iterator<E>
         | 
        
        iterator()
        
        Returns an instance of  Iterator that may be used to access the
 objects contained by this  Collection.  
  
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            boolean
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        remove(Object object)
        
         Removes one instance of the specified object from this Collection if one
 is contained (optional). 
  
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            boolean
         | 
        
        removeAll(Collection<?> collection)
        
         Removes all occurrences in this Collection of each object in the
 specified Collection (optional). 
  
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            boolean
         | 
        
        retainAll(Collection<?> collection)
        
         Removes all objects from this Collection that are not also found in the
 Collection passed (optional). 
  
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            abstract
            
            
            
            
            int
         | 
        
        size()
        
         Returns a count of how many objects this Collection contains. 
  
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            <T>
            T[]
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        toArray(T[] contents)
        
         Returns an array containing all elements contained in this Collection. 
  
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            Object[]
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        toArray()
        
         Returns a new array containing all elements contained in this Collection. 
  
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            String
         | 
        
        toString()
        
         Returns the string representation of this Collection. 
  
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From class
  java.lang.Object
  
   
  
    
    
	 
    
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            Object
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        clone()
        
         Creates and returns a copy of this Object. 
  
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            boolean
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        equals(Object o)
        
         Compares this instance with the specified object and indicates if they
 are equal. 
  
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            void
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        finalize()
        
         Invoked when the garbage collector has detected that this instance is no longer reachable. 
  
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            final
            
            
            Class<?>
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        getClass()
        
        Returns the unique instance of  Class that represents this
 object's class.  
  
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            int
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        hashCode()
        
         Returns an integer hash code for this object. 
  
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            final
            
            
            void
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        notify()
        
         Causes a thread which is waiting on this object's monitor (by means of
 calling one of the wait() methods) to be woken up. 
  
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            final
            
            
            void
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        notifyAll()
        
         Causes all threads which are waiting on this object's monitor (by means
 of calling one of the wait() methods) to be woken up. 
  
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            String
         | 
        
        toString()
        
         Returns a string containing a concise, human-readable description of this
 object. 
  
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            final
            
            
            void
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        wait()
        
         Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object. 
  
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            final
            
            
            void
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        wait(long millis, int nanos)
        
         Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the
 specified timeout expires. 
  
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            final
            
            
            void
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        wait(long millis)
        
         Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the
 specified timeout expires. 
  
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From interface
  java.lang.Iterable
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From interface
  java.util.Collection
  
   
  
    
    
	 
    
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            abstract
            
            
            
            
            boolean
         | 
        
        add(E object)
        
         Attempts to add object to the contents of this
 Collection (optional). 
  
   |  
	 
    
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            abstract
            
            
            
            
            boolean
         | 
        
        addAll(Collection<? extends E> collection)
        
         Attempts to add all of the objects contained in Collection
 to the contents of this Collection (optional). 
  
   |  
	 
    
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            abstract
            
            
            
            
            void
         | 
        
        clear()
        
         Removes all elements from this Collection, leaving it empty (optional). 
  
   |  
	 
    
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            abstract
            
            
            
            
            boolean
         | 
        
        contains(Object object)
        
         Tests whether this Collection contains the specified object. 
  
   |  
	 
    
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            abstract
            
            
            
            
            boolean
         | 
        
        containsAll(Collection<?> collection)
        
         Tests whether this Collection contains all objects contained in the
 specified Collection. 
  
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        | 
            abstract
            
            
            
            
            boolean
         | 
        
        equals(Object object)
        
         Compares the argument to the receiver, and returns true if they represent
 the same object using a class specific comparison. 
  
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            abstract
            
            
            
            
            int
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        hashCode()
        
         Returns an integer hash code for the receiver. 
  
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            abstract
            
            
            
            
            boolean
         | 
        
        isEmpty()
        
         Returns if this Collection contains no elements. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            Iterator<E>
         | 
        
        iterator()
        
        Returns an instance of  Iterator that may be used to access the
 objects contained by this  Collection.  
  
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        | 
            abstract
            
            
            
            
            boolean
         | 
        
        remove(Object object)
        
         Removes one instance of the specified object from this Collection if one
 is contained (optional). 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        removeAll(Collection<?> collection)
        
         Removes all occurrences in this Collection of each object in the
 specified Collection (optional). 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        retainAll(Collection<?> collection)
        
         Removes all objects from this Collection that are not also found in the
 Collection passed (optional). 
  
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            abstract
            
            
            
            
            int
         | 
        
        size()
        
         Returns a count of how many objects this Collection contains. 
  
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            abstract
            
            
            
            <T>
            T[]
         | 
        
        toArray(T[] array)
        
         Returns an array containing all elements contained in this Collection. 
  
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            abstract
            
            
            
            
            Object[]
         | 
        
        toArray()
        
         Returns a new array containing all elements contained in this Collection. 
  
   |  
 
   
 
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From interface
  java.util.Set
  
   
  
    
    
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        add(E object)
        
         Adds the specified object to this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        addAll(Collection<? extends E> collection)
        
         Adds the objects in the specified collection which do not exist yet in
 this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            void
         | 
        
        clear()
        
         Removes all elements from this set, leaving it empty. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        contains(Object object)
        
         Searches this set for the specified object. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        containsAll(Collection<?> collection)
        
         Searches this set for all objects in the specified collection. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        equals(Object object)
        
         Compares the specified object to this set, and returns true if they
 represent the same object using a class specific comparison. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            int
         | 
        
        hashCode()
        
         Returns the hash code for this set. 
  
   |  
	 
    
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            abstract
            
            
            
            
            boolean
         | 
        
        isEmpty()
        
         Returns true if this set has no elements. 
  
   |  
	 
    
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            abstract
            
            
            
            
            Iterator<E>
         | 
        
        iterator()
        
         Returns an iterator on the elements of this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        remove(Object object)
        
         Removes the specified object from this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        removeAll(Collection<?> collection)
        
         Removes all objects in the specified collection from this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            boolean
         | 
        
        retainAll(Collection<?> collection)
        
         Removes all objects from this set that are not contained in the specified
 collection. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            int
         | 
        
        size()
        
         Returns the number of elements in this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            <T>
            T[]
         | 
        
        toArray(T[] array)
        
         Returns an array containing all elements contained in this set. 
  
   |  
	 
    
        | 
            abstract
            
            
            
            
            Object[]
         | 
        
        toArray()
        
         Returns an array containing all elements contained in this set. 
  
   |  
 
   
 
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Public Constructors
 
    
      
        public 
         
         
         
         
        
      
      LinkedHashSet
      ()
    
      
    
      
  Constructs a new empty instance of LinkedHashSet.
 
     
 
 
    
      
        public 
         
         
         
         
        
      
      LinkedHashSet
      (int capacity)
    
      
    
      
  Constructs a new instance of LinkedHashSet with the specified
 capacity.
 
  
      Parameters
      
        
          | capacity
           | the initial capacity of this LinkedHashSet.
 | 
        
      
   
     
 
 
    
      
        public 
         
         
         
         
        
      
      LinkedHashSet
      (int capacity, float loadFactor)
    
      
    
      
  Constructs a new instance of LinkedHashSet with the specified
 capacity and load factor.
 
  
      Parameters
      
        
          | capacity
           | the initial capacity. | 
        
        
          | loadFactor
           | the initial load factor.
 | 
        
      
   
     
 
 
    
      
        public 
         
         
         
         
        
      
      LinkedHashSet
      (Collection<? extends E> collection)
    
      
    
      
  Constructs a new instance of LinkedHashSet containing the unique
 elements in the specified collection.
 
  
      Parameters
      
        
          | collection
           | the collection of elements to add.
 |