java.util
Class HashSet

java.lang.Object
  java.util.AbstractCollection
      java.util.AbstractSet
          java.util.HashSet

All Implemented Interfaces:

Cloneable, Collection, Serializable, Set

Direct Known Subclasses:

JTypeDeclaration.PleomorphSet, LinkedHashSet

public class HashSet

extends AbstractSet

implements Set, Cloneable, Serializable

JML's specification of java.util.HashSet.

Author:

Katie Becker, Gary T. Leavens

Class Specifications

public invariant this.initialCapacity >= 0; public invariant this.loadFactor > 0.0; public represents addOperationSupported <- true; public represents removeOperationSupported <- true;

Specifications inherited from class Object

represents objectState <- org.jmlspecs.lang.JMLDataGroup.IT; public represents _getClass <- \typeof(this);

Specifications inherited from interface Set

instance public represents theCollection <- this.theSet.toBag();

Specifications inherited from interface Collection

instance public invariant this.elementType == this.theCollection.elementType; instance public invariant this.containsNull == this.theCollection.containsNull; instance public invariant !this.nullElementsSupported ==> !this.containsNull;

Model Field Summary
int	initialCapacity
float	loadFactor

 

Model fields inherited from class java.lang.Object

_getClass, objectState, theString

 

Model fields inherited from interface java.util.Set

theSet

 

Model fields inherited from interface java.util.Collection

addOperationSupported, elementState, nullElementsSupported, removeOperationSupported, theCollection

 

Ghost Field Summary

 

Ghost fields inherited from class java.lang.Object

objectTimesFinalized, owner

 

Ghost fields inherited from interface java.util.Collection

containsNull, elementType

 

Field Summary
(package private) static long	serialVersionUID

 

Constructor Summary
	HashSet()
	HashSet(int initialCapacity)
	HashSet(int initialCapacity, float loadFactor)
(package private)	HashSet(int initialCapacity, float loadFactor, boolean dummy)
	HashSet(Collection c)

 

Model Method Summary

 

Model methods inherited from class java.lang.Object

hashValue

 

Model methods inherited from interface java.util.Collection

hashValue

 

Method Summary
boolean	add(nullable Object o)
void	clear()
Object	clone()
boolean	contains(nullable Object o)
boolean	isEmpty()
Iterator	iterator()
boolean	remove(nullable Object o)
int	size()

 

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

 

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, retainAll, toArray, toArray, toString

 

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

 

Methods inherited from interface java.util.Set

addAll, containsAll, equals, hashCode, removeAll, retainAll, toArray, toArray

 

Model Field Detail

initialCapacity

public int initialCapacity

loadFactor

public float loadFactor

serialVersionUID

static final long serialVersionUID

HashSet

public HashSet()

Specifications:

public normal_behavior
assignable theSet, initialCapacity, loadFactor;
ensures this.theSet != null&&this.theSet.isEmpty();
ensures this.loadFactor == 0.75;
ensures this.initialCapacity == 16;

HashSet

public HashSet(Collection c)

Specifications:

public normal_behavior
requires c != null;
assignable theSet, initialCapacity, loadFactor;
ensures this.loadFactor == 0.75&&this.theSet.equals(org.jmlspecs.models.JMLEqualsSet.convertFrom(c));

HashSet

public HashSet(int initialCapacity,
               float loadFactor)

Specifications:

public normal_behavior
requires initialCapacity >= 0;
assignable theSet, this.initialCapacity, this.loadFactor;
ensures this.theSet != null&&this.theSet.isEmpty();
ensures this.initialCapacity == initialCapacity&&this.loadFactor == loadFactor;

HashSet

public HashSet(int initialCapacity)

Specifications:

public normal_behavior
assignable theSet, this.initialCapacity, this.loadFactor;
ensures this.theSet != null&&this.theSet.isEmpty();
ensures this.initialCapacity == initialCapacity&&this.loadFactor == 0.75;

HashSet

HashSet(int initialCapacity,
        float loadFactor,
        boolean dummy)

iterator

public Iterator iterator()

Specified by:

iterator in interface Set

Specifications: pure

Specifications inherited from overridden method in class AbstractCollection:
       pure

Specifications inherited from overridden method in interface Set:
       pure

Specifications inherited from overridden method in interface Collection:
       pure non_null

public normal_behavior
assignable \nothing;
ensures \result != null;
ensures \result .elementType == this.elementType;
ensures this.containsNull == \result .returnsNull;

     also

public normal_behavior
ensures ( \forall int i; 0 <= i&&i < this.size(); this.theCollection.has(\result .nthNextElement(i)));
ensures ( \forall java.lang.Object o; ; this.theCollection.has(o) ==> ( \exists int i; 0 <= i&&i < this.size(); o.equals(\result .nthNextElement(i))));
ensures this.size() > 0 ==> \result .hasNext((int)(this.size()-1));
ensures !\result .hasNext((int)(this.size()));
ensures_redundantly ( \forall int i; 0 <= i&&i < this.size(); this.contains(\result .nthNextElement(i)));
ensures_redundantly this.size() != 0 ==> \result .moreElements;

size

public int size()

Specified by:

size in interface Set

Specifications: pure

Specifications inherited from overridden method in class AbstractCollection:
       pure

Specifications inherited from overridden method in interface Set:
       pure

Specifications inherited from overridden method in interface Collection:
       pure

public normal_behavior
assignable \nothing;
ensures \result == this.theCollection.int_size();
ensures \result >= 0;

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Set

Overrides:

isEmpty in class AbstractCollection

Specifications: pure

Specifications inherited from overridden method in class AbstractCollection:
       pure

Specifications inherited from overridden method in interface Set:
       pure

Specifications inherited from overridden method in interface Collection:
       pure

public normal_behavior
assignable \nothing;
ensures \result <==> this.theCollection.isEmpty();

     also

public normal_behavior
ensures \result == (this.size() == 0);

contains

public boolean contains(nullable Object o)

Specified by:

contains in interface Set

Overrides:

contains in class AbstractCollection

Specifications: pure

Specifications inherited from overridden method in class AbstractCollection:
       pure

Specifications inherited from overridden method in interface Set:
       pure

Specifications inherited from overridden method contains(Object o) in interface Collection:
       pure

public behavior
assignable \nothing;
ensures !this.containsNull&&o == null ==> !\result ;
ensures (o == null)||\typeof(o) <: this.elementType||!\result ;
ensures \result <==> this.theCollection.has(o);
signals_only java.lang.ClassCastException, java.lang.NullPointerException;
signals (java.lang.ClassCastException) (* \typeof(o) is incompatible with the elementType of this collection *);
signals (java.lang.NullPointerException) o == null;

add

public boolean add(nullable Object o)

Specified by:

add in interface Set

Overrides:

add in class AbstractCollection

Specifications inherited from overridden method in class AbstractCollection:
      --- None ---

Specifications inherited from overridden method add(Object o) in interface Set:

     also

public behavior
assignable theCollection;
ensures \result <==> !\old(this.theSet.has(o));
ensures this.theSet.equals(\old(this.theSet.insert(o)));

Specifications inherited from overridden method add(Object o) in interface Collection:

public behavior
requires !this.containsNull ==> o != null;
requires (o == null)||\typeof(o) <: this.elementType;
assignable theCollection;
ensures \result ==> this.theCollection.equals(\old(this.theCollection.insert(o)));
ensures \result &&\old(this.size() < 2147483647) ==> this.size() == \old(this.size()+1);
ensures !\result ==> this.size() == \old(this.size());
ensures !\result ==> \not_modified(theCollection);
ensures this.contains(o);
ensures_redundantly !\result ==> \old(this.contains(o));
signals_only java.lang.UnsupportedOperationException, java.lang.NullPointerException, java.lang.ClassCastException, java.lang.IllegalArgumentException;
signals (java.lang.UnsupportedOperationException) (* this does not support add *);
signals (java.lang.NullPointerException) (* not allowed to add null *);
signals (java.lang.ClassCastException) (* class of specified element prevents it from being added to this *);
signals (java.lang.IllegalArgumentException) (* some aspect of this element prevents it from being added to this *);

remove

public boolean remove(nullable Object o)

Specified by:

remove in interface Set

Overrides:

remove in class AbstractCollection

Specifications inherited from overridden method in class AbstractCollection:
      --- None ---

Specifications inherited from overridden method remove(Object o) in interface Set:

    implies_that

public behavior
assignable theCollection;
assignable_redundantly theSet;
ensures !this.theSet.has(o);
ensures_redundantly !this.theCollection.has(o);

Specifications inherited from overridden method remove(Object o) in interface Collection:

public behavior
requires !this.containsNull ==> o != null;
requires (o == null)||\typeof(o) <: this.elementType;
assignable theCollection;
ensures \result ==> this.theCollection.equals(\old(this.theCollection.remove(o)));
ensures \result &&\old(this.size() <= 2147483647) ==> this.size() == \old(this.size()-1)&&this.size() < 2147483647&&this.size() >= 0;
ensures !\result ||\old(this.size() == 2147483647) ==> this.size() == \old(this.size());
signals_only java.lang.UnsupportedOperationException, java.lang.ClassCastException;
signals (java.lang.UnsupportedOperationException) (* this does not support remove *);
signals (java.lang.ClassCastException) (* the type of this element is not compatible with this *);

clear

public void clear()

Specified by:

clear in interface Set

Overrides:

clear in class AbstractCollection

Specifications inherited from overridden method in class AbstractCollection:
      --- None ---

Specifications inherited from overridden method in interface Set:
      --- None ---

Specifications inherited from overridden method in interface Collection:

public behavior
assignable theCollection;
ensures this.theCollection.isEmpty();
ensures_redundantly this.size() == 0;
signals_only java.lang.UnsupportedOperationException;
signals (java.lang.UnsupportedOperationException) (* clear is not supported by this *);

clone

public Object clone()

Overrides:

clone in class Object

Specifications:

     also

public normal_behavior
assignable \nothing;
ensures \result instanceof java.util.Set&&\fresh(\result )&&((java.util.Set)\result ).equals(this);
ensures_redundantly \result != this;

Specifications inherited from overridden method in class Object:
       non_null

protected normal_behavior
requires this instanceof java.lang.Cloneable;
assignable \nothing;
ensures \result != null;
ensures \typeof(\result ) == \typeof(this);
ensures (* \result is a clone of this *);

     also

protected normal_behavior
requires this.getClass().isArray();
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((java.lang.Object[])\result ).length == ((java.lang.Object[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((java.lang.Object[])this).length; ((java.lang.Object[])\result )[i] == ((java.lang.Object[])this)[i]);

     also

requires this.getClass().isArray();
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures java.lang.reflect.Array.getLength(\result ) == java.lang.reflect.Array.getLength(this);
ensures ( \forall int i; 0 <= i&&i < java.lang.reflect.Array.getLength(this); ( \exists java.lang.Object result_i; result_i == java.lang.reflect.Array.get(\result ,i); (result_i == null&&java.lang.reflect.Array.get(this,i) == null)||(result_i != null&&result_i.equals(java.lang.reflect.Array.get(this,i)))));

     also

protected exceptional_behavior
requires !(this instanceof java.lang.Cloneable);
assignable \nothing;
signals_only java.lang.CloneNotSupportedException;

     also

protected normal_behavior
requires \elemtype(\typeof(this)) <: \type(java.lang.Object);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((java.lang.Object[])\result ).length == ((java.lang.Object[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((java.lang.Object[])this).length; ((java.lang.Object[])\result )[i] == ((java.lang.Object[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(int);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((int[])\result ).length == ((int[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((int[])this).length; ((int[])\result )[i] == ((int[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(byte);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((byte[])\result ).length == ((byte[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((byte[])this).length; ((byte[])\result )[i] == ((byte[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(char);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((char[])\result ).length == ((char[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((char[])this).length; ((char[])\result )[i] == ((char[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(long);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((long[])\result ).length == ((long[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((long[])this).length; ((long[])\result )[i] == ((long[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(short);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((short[])\result ).length == ((short[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((short[])this).length; ((short[])\result )[i] == ((short[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(boolean);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((boolean[])\result ).length == ((boolean[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((boolean[])this).length; ((boolean[])\result )[i] == ((boolean[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(float);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((float[])\result ).length == ((float[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((float[])this).length; (java.lang.Float.isNaN(((float[])\result )[i])&&java.lang.Float.isNaN(((float[])this)[i]))||((float[])\result )[i] == ((float[])this)[i]);

     also

protected normal_behavior
requires \elemtype(\typeof(this)) == \type(double);
assignable \nothing;
ensures \elemtype(\typeof(\result )) == \elemtype(\typeof(this));
ensures ((double[])\result ).length == ((double[])this).length;
ensures ( \forall int i; 0 <= i&&i < ((double[])this).length; (java.lang.Double.isNaN(((double[])\result )[i])&&java.lang.Double.isNaN(((double[])this)[i]))||((double[])\result )[i] == ((double[])this)[i]);