org.jmlspecs.models
Class JMLObjectSequence

java.lang.Object
  org.jmlspecs.models.JMLObjectSequence

All Implemented Interfaces:

Cloneable, JMLCollection, JMLType, Serializable

public class JMLObjectSequence

extends Object

implements JMLCollection

Sequences of objects. This type uses "==" to compare elements, and does not clone elements that are passed into and returned from the sequence's methods.

The informal model for a JMLObjectSequence is a finite mathematical sequence of elements (of type Object). In some examples, we will write <a,b,c> for a mathematical sequence of length 3, containing elements a, b, and c. Elements of sequences are "indexed" from 0, so the length of a sequence is always 1 more than the index of the last element in the sequence.

Version:

$Revision: 1.81 $

Author:

Gary T. Leavens, Albert L. Baker

See Also:

JMLCollection, JMLType, JMLValueSequence, JMLObjectSequenceEnumerator

Class Specifications

public invariant ( \forall org.jmlspecs.models.JMLObjectSequence s2; ; ( \forall java.lang.Object e1, e2; ; ( \forall \bigint n; ; this.equational_theory(this,s2,e1,e2,n)))); public invariant this.elementType <: \type(java.lang.Object); public invariant ( \forall java.lang.Object o; o != null&&this.has(o); \typeof(o) <: this.elementType); public invariant_redundantly this.isEmpty() ==> !this.containsNull; invariant this.theSeq != null ==> this.theSeq.owner == this; protected invariant this.theSeq == null <==> this.length == 0; protected invariant this.length >= 0; protected invariant this.theSeq != null ==> this.length == this.theSeq.length(); protected invariant this.length == this.length(); public invariant this.owner == null; protected represents length <- bigIntegerToBigint(this._length);

Specifications inherited from class Object

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

Specifications inherited from interface JMLCollection

instance public constraint this.elementType == \old(this.elementType); instance public constraint this.containsNull == \old(this.containsNull);

Model Field Summary
\bigint	length

 

Model fields inherited from class java.lang.Object

_getClass, objectState, theString

 

Model fields inherited from interface org.jmlspecs.models.JMLCollection

elementState

 

Ghost Field Summary

 

Ghost fields inherited from class java.lang.Object

objectTimesFinalized, owner

 

Ghost fields inherited from interface org.jmlspecs.models.JMLCollection

containsNull, elementType

 

Field Summary
protected  BigInteger	_length           This sequence's length.
static JMLObjectSequence	EMPTY           The empty JMLObjectSequence.
private static String	IS_NOT_FOUND
private static String	ITEM_PREFIX
protected  JMLListObjectNode	theSeq           The list representing this sequence's elements, in order.
private static String	TOO_BIG_TO_INSERT

 

Model Constructor Summary
protected	JMLObjectSequence(JMLListObjectNode ls, \bigint len)           Initialize this sequence based on the given representation.

 

Constructor Summary
	JMLObjectSequence()           Initialize this to be the empty sequence.
	JMLObjectSequence(Object e)           Initialize this to be the sequence containing just the given element.
protected	JMLObjectSequence(JMLListObjectNode ls, int len)           Initialize this sequence based on the given representation.

 

Model Method Summary
\bigint	bi_count(Object item)           Tells the number of times a given element occurs in the sequence.
\bigint	bi_indexOf(Object item)           Return the zero-based index of the first occurrence of the given element in the sequence, if there is one
static \bigint	bigIntegerToBigint(BigInteger oBi)
static BigInteger	bigintToBigInteger(\bigint biValue)
boolean	equational_theory(JMLObjectSequence s, JMLObjectSequence s2, Object e1, Object e2, \bigint n)           An equational specification of the properties of sequences.
Object	get(\bigint i)           Return the element at the given zero-based index; a synonym for itemAt(int).
JMLObjectSequence	insertAfterIndex(\bigint afterThisOne, Object item)           Return a sequence like this, but with item put immediately after the given index.
JMLObjectSequence	insertBeforeIndex(\bigint beforeThisOne, Object item)           Return a sequence like this, but with item put immediately before the given index.
Object	itemAt(\bigint i)           Return the element at the given zero-based index.
\bigint	length()           Tells the number of elements in the sequence; a synonym for #length.
JMLObjectSequence	prefix(\bigint n)           Return a sequence containing the first n elements in this sequence.
JMLObjectSequence	removeItemAt(\bigint index)           Return a sequence like this, but without the element at the given zero-based index.
JMLObjectSequence	removePrefix(\bigint n)           Return a sequence containing all but the first n elements in this.
JMLObjectSequence	replaceItemAt(\bigint index, Object item)           Return a sequence like this, but with item replacing the element at the given zero-based index.
\bigint	size()           Tells the number of elements in the sequence; a synonym for #length.
JMLObjectSequence	subsequence(\bigint from, \bigint to)           Returns a subsequence of this containing the elements beginning with index from (inclusive) and ending with index to (exclusive).

 

Model methods inherited from class java.lang.Object

hashValue

 

Method Summary
Object	clone()           Return a clone of this object.
JMLObjectSequence	concat(non_null JMLObjectSequence s2)           Return a sequence that is the concatenation of this with the given sequence.
boolean	containsAll(non_null Collection c)           Tell whether, for each element in the given collection, there is a "==" element in this sequence.
static JMLObjectSequence	convertFrom(non_null Object[] a)           Return the sequence containing all the elements in the given array in the same order as the elements appear in the array.
static JMLObjectSequence	convertFrom(non_null Object[] a, int size)           Return the sequence containing the first 'size' elements in the given array in the same order as the elements appear in the array.
static JMLObjectSequence	convertFrom(non_null Collection c)           Return the sequence containing all the object in the given collection in the same order as the elements appear in the collection.
static JMLObjectSequence	convertFrom(non_null JMLCollection c)           Return the sequence containing all the object in the given JMLCollection in the same order as the elements appear in the collection.
int	count(Object item)           Tells the number of times a given element occurs in the sequence.
JMLObjectSequenceEnumerator	elements()           Return a enumerator for this.
boolean	equals(nullable Object obj)           Test whether this object's value is equal to the given argument.
Object	first()           Return the first element in this sequence.
Object	get(int i)           Return the element at the given zero-based index; a synonym for itemAt(int).
boolean	has(Object elem)           Tells whether the given element is "==" to an element in the sequence.
int	hashCode()           Return a hash code for this object.
JMLObjectSequence	header()           Return a sequence containing all but the last element in this.
int	indexOf(Object item)           Return the zero-based index of the first occurrence of the given element in the sequence, if there is one
JMLObjectSequence	insertAfterIndex(int afterThisOne, Object item)           Return a sequence like this, but with item put immediately after the given index.
JMLObjectSequence	insertBack(Object item)           Return a sequence like this, but with the given item put an the end.
JMLObjectSequence	insertBeforeIndex(int beforeThisOne, Object item)           Return a sequence like this, but with item put immediately before the given index.
JMLObjectSequence	insertFront(Object item)           Return a sequence like this, but with the given item put an the front.
int	int_length()           Tells the number of elements in the sequence; a synonym for #size.
int	int_size()           Tells the number of elements in the sequence; a synonym for #length.
boolean	isDeletionFrom(non_null JMLObjectSequence s2, Object elem)           Tells whether this sequence is the result of deleting the given element once from the given sequence.
boolean	isEmpty()           Tells whether this sequence is empty.
boolean	isInsertionInto(non_null JMLObjectSequence s2, Object elem)           Tells whether this sequence is the result of inserting the given element once into the given sequence.
boolean	isPrefix(non_null JMLObjectSequence s2)           Tells whether the elements of the this sequence occur, in order, at the beginning of the given sequence, using "==" for comparisons.
boolean	isProperPrefix(non_null JMLObjectSequence s2)           Tells whether this sequence is shorter than the given sequence, and also if the elements of this sequence occur, in order, at the beginning of the given sequence, using "==" for comparisons.
boolean	isProperSubsequence(non_null JMLObjectSequence s2)           Tells whether this sequence is strictly shorter than the given sequence and a subsequence of it.
boolean	isProperSuffix(non_null JMLObjectSequence s2)           Tells whether the this sequence is shorter than the given object, and also if the elements of this sequence occur, in order, at the end of the given sequence, using "==" for comparisons.
boolean	isProperSupersequence(non_null JMLObjectSequence s2)           Tells whether the given sequence is both longer than and a supersequence of this sequence.
boolean	isSubsequence(non_null JMLObjectSequence s2)           Tells whether this sequence is a subsequence of the given sequence.
boolean	isSuffix(non_null JMLObjectSequence s2)           Tells whether the elements of this sequence occur, in order, at the end of the given sequence, using "==" for comparisons.
boolean	isSupersequence(non_null JMLObjectSequence s2)           Tells whether the given sequence is a supersequence of this sequence.
Object	itemAt(int i)           Return the element at the given zero-based index.
JMLIterator	iterator()           Returns an iterator over this sequence.
Object	last()           Return the last element in this sequence.
JMLObjectSequence	prefix(int n)           Return a sequence containing the first n elements in this sequence.
JMLObjectSequence	removeItemAt(int index)           Return a sequence like this, but without the element at the given zero-based index.
JMLObjectSequence	removePrefix(int n)           Return a sequence containing all but the first n elements in this.
JMLObjectSequence	replaceItemAt(int index, Object item)           Return a sequence like this, but with item replacing the element at the given zero-based index.
JMLObjectSequence	reverse()           Return a sequence that is the reverse of this sequence.
static JMLObjectSequence	singleton(Object e)           Return the singleton sequence containing the given element.
JMLObjectSequence	subsequence(int from, int to)           Returns a subsequence of this containing the elements beginning with index from (inclusive) and ending with index to (exclusive).
Object[]	toArray()           Return a new array containing all the elements of this in order.
JMLObjectBag	toBag()           Return a new JMLObjectBag containing all the elements of this.
JMLObjectSet	toSet()           Return a new JMLObjectSet containing all the elements of this.
String	toString()           Return a string representation of this object.
JMLObjectSequence	trailer()           Return a sequence containing all but the first element in this.

 

Methods inherited from class java.lang.Object

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

 

Model Field Detail

length

public \bigint length

theSeq

protected final JMLListObjectNode theSeq

The list representing this sequence's elements, in order.

Specifications:
is in groups: objectState
maps theSeq.elementState \into elementState

_length

protected final BigInteger _length

This sequence's length.

Specifications:
is in groups: objectState

EMPTY

public static final JMLObjectSequence EMPTY

The empty JMLObjectSequence.

See Also:

JMLObjectSequence()

Specifications: non_null

ITEM_PREFIX

private static final String ITEM_PREFIX

IS_NOT_FOUND

private static final String IS_NOT_FOUND

TOO_BIG_TO_INSERT

private static final String TOO_BIG_TO_INSERT

JMLObjectSequence

protected JMLObjectSequence(JMLListObjectNode ls,
                            \bigint len)

Initialize this sequence based on the given representation.

Specifications: (class)pure

requires ls == null <==> len == 0;
requires len >= 0;
assignable objectState, elementType, containsNull, owner;
ensures ls != null ==> this.elementType == ls.elementType;
ensures ls != null ==> this.containsNull == ls.containsNull;
ensures ls == null ==> this.elementType <: \type(java.lang.Object);
ensures ls == null ==> !this.containsNull;

JMLObjectSequence

public JMLObjectSequence()

Initialize this to be the empty sequence.

See Also:

EMPTY

Specifications: (class)pure

public normal_behavior
assignable objectState, elementType, containsNull, owner;
ensures this.isEmpty();
ensures_redundantly this.size() == 0;
ensures_redundantly (* this is an empty sequence *);

    implies_that

ensures this.elementType <: \type(java.lang.Object)&&!this.containsNull;

JMLObjectSequence

public JMLObjectSequence(Object e)

Initialize this to be the sequence containing just the given element.

Parameters:

e - the element that is the first element in this sequence.

See Also:

singleton(java.lang.Object)

Specifications: (class)pure

public normal_behavior
assignable objectState, elementType, containsNull, owner;
ensures this.int_length() == 1;
ensures (e == null ==> this.itemAt(0) == null)&&(e != null ==> this.itemAt(0) == e);
ensures_redundantly (* this is a sequence containing just e *);

JMLObjectSequence

protected JMLObjectSequence(JMLListObjectNode ls,
                            int len)

Initialize this sequence based on the given representation.

Specifications: (class)pure

requires ls == null <==> len == 0;
requires len >= 0;
assignable objectState, elementType, containsNull, owner;
ensures ls != null ==> this.elementType == ls.elementType;
ensures ls != null ==> this.containsNull == ls.containsNull;
ensures ls == null ==> this.elementType <: \type(java.lang.Object);
ensures ls == null ==> !this.containsNull;

equational_theory

public boolean equational_theory(JMLObjectSequence s,
                                 JMLObjectSequence s2,
                                 Object e1,
                                 Object e2,
                                 \bigint n)

An equational specification of the properties of sequences.

Specifications: pure

public normal_behavior

{|

ensures \result <==> !(new org.jmlspecs.models.JMLObjectSequence()).has(e1);

also

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence()).size() == 0;

also

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence(e1)).size() == 1;

also

ensures \result <==> e1 != null ==> (new org.jmlspecs.models.JMLObjectSequence(e1)).itemAt(0) == e1;

also

ensures \result <==> e1 != null ==> s.insertFront(e1).first() == e1;

also

ensures \result <==> e1 != null ==> s.insertBack(e1).last() == e1;

also

ensures \result <==> e1 != null ==> s.insertFront(e1).itemAt(0) == e1;

also

ensures \result <==> s.insertFront(e1).size() == s.size()+1;

also

ensures \result <==> e1 != null ==> s.insertBack(e1).itemAt(s.size()) == e1;

also

ensures \result <==> s.insertBack(e1).size() == s.size()+1;

also

ensures \result <==> -1 <= n&&n < s.size()&&e1 != null ==> s.insertAfterIndex(n,e1).itemAt(n+1) == e1;

also

ensures \result <==> -1 <= n&&n < s.size() ==> s.insertAfterIndex(n,e1).size() == s.size()+1;

also

ensures \result <==> 0 <= n&&n <= s.size()&&e1 != null ==> s.insertBeforeIndex(n,e1).itemAt(n) == e1;

also

ensures \result <==> 0 <= n&&n <= s.size() ==> s.insertBeforeIndex(n,e1).size() == s.size()+1;

also

ensures \result <==> s.isPrefix(s2) == ( \forall int i; 0 <= i&&i < s.int_length(); (s2.itemAt(i) != null&&s2.itemAt(i) == (s.itemAt(i)))||(s2.itemAt(i) == null&&s.itemAt(i) == null));

also

ensures \result <==> s.isSubsequence(s2) == s.int_length() <= s2.int_length()&&(s.isPrefix(s2)||s.isSubsequence(s2.trailer()));

also

ensures \result <==> s.isEmpty() == (s.size() == 0);

also

ensures \result <==> s.isEmpty() == (s.length == 0);

also

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence(e1)).equals(new org.jmlspecs.models.JMLObjectSequence().insertFront(e1));

also

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence(e1)).equals(new org.jmlspecs.models.JMLObjectSequence().insertBack(e1));

also

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence(e1)).equals(new org.jmlspecs.models.JMLObjectSequence().insertAfterIndex(-1,e1));

also

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence(e1)).equals(new org.jmlspecs.models.JMLObjectSequence().insertBeforeIndex(0,e1));

also

ensures \result <==> (s.size() >= 1 ==> s.equals(s.trailer().insertFront(s.first())));

also

ensures \result <==> (s.size() >= 1 ==> s.equals(s.header().insertBack(s.last())));

also

ensures \result <==> s.isProperSubsequence(s2) == (s.isSubsequence(s2)&&!s.equals(s2));

also

ensures \result <==> s.isSupersequence(s2) == s2.isSubsequence(s);

also

ensures \result <==> s.isProperSupersequence(s2) == s2.isProperSubsequence(s);

|}

    implies_that

ensures \result <==> (new org.jmlspecs.models.JMLObjectSequence()).isEmpty();

itemAt

public Object itemAt(\bigint i)
              throws JMLSequenceException

Return the element at the given zero-based index.

Parameters:

i - the zero-based index into the sequence.

Throws:

JMLSequenceException - if the index oBiI is out of range.

See Also:

get(int), has(Object), count(Object)

Specifications: (class)pure

public normal_behavior
requires 0 <= i&&i < this.length;
ensures (* \result == null, if the ith element of this is null; otherwise, \result "==" the ith element of this *);
ensures \result != null ==> \typeof(\result ) <: this.elementType;
ensures !this.containsNull ==> \result != null;

     also

public exceptional_behavior
requires !(0 <= i&&i < this.length);
signals_only org.jmlspecs.models.JMLSequenceException;

    for_example

public normal_example
requires (* this is <w,x,y,z> and i is 0 *);
ensures (* \result is w *);

       also

public normal_example
requires (* this is <w,x,y,z> and i is 3 *);
ensures (* \result is z *);

get

public Object get(\bigint i)
           throws IndexOutOfBoundsException

Return the element at the given zero-based index; a synonym for itemAt(int).

Parameters:

i - the zero-based index into the sequence.

Throws:

IndexOutOfBoundsException - if the index i is out of range.

See Also:

#itemAt(\bigint)

Specifications: (class)pure

public normal_behavior
requires 0 <= i&&i < this.length;
ensures (* \result == null, if the ith element of this is null; otherwise, \result "==" the ith element of this *);

     also

public exceptional_behavior
requires !(0 <= i&&i < this.length);
signals_only java.lang.IndexOutOfBoundsException;

    implies_that

ensures \result != null ==> \typeof(\result ) <: this.elementType;
ensures !this.containsNull ==> \result != null;

size

public \bigint size()

Tells the number of elements in the sequence; a synonym for #length.

See Also:

#length(), isEmpty()

Specifications: pure

Specifications inherited from overridden method in interface JMLCollection:
       pure

public normal_behavior
ensures \result >= 0&&(* \result is the size of this collection *);

length

public \bigint length()

Tells the number of elements in the sequence; a synonym for #length.

See Also:

#size(), isEmpty()

Specifications: pure

bi_count

public \bigint bi_count(Object item)

Tells the number of times a given element occurs in the sequence.

See Also:

has(Object), itemAt(int)

Specifications: (class)pure

public normal_behavior
requires item != null;
ensures \result == ( \num_of \bigint i; 0 <= i&&i < this.length(); this.itemAt(i) != null&&this.itemAt(i) == item);

     also

public normal_behavior
requires item == null;
ensures \result == ( \num_of \bigint i; 0 <= i&&i < this.length(); this.itemAt(i) == null);

    implies_that

ensures \result >= 0;

    for_example

public normal_example
requires (* this is <a,b,c,d,c> and item is c *);
ensures \result == 2;

       also

public normal_example
requires (* this is <a,b,c,d,a> and item is q *);
ensures \result == 0;

bi_indexOf

public \bigint bi_indexOf(Object item)
                   throws JMLSequenceException

Return the zero-based index of the first occurrence of the given element in the sequence, if there is one

Parameters:

item - the Object sought in this.

Returns:

the first index at which item occurs.

Throws:

JMLSequenceException - if item is not a member of the sequence.

See Also:

itemAt(int)

Specifications: (class)pure

public normal_behavior
requires this.has(item);

{|

requires item != null;
ensures this.itemAt(\result ) == item&&( \forall \bigint i; 0 <= i&&i < \result ; !(this.itemAt(i) == item));
ensures_redundantly (* \result is the first index at which item occurs in this *);

also

requires item == null;
ensures this.itemAt(\result ) == null&&( \forall \bigint i; 0 <= i&&i < \result ; this.itemAt(i) != null);

|}

     also

public exceptional_behavior
requires !this.has(item);
signals_only org.jmlspecs.models.JMLSequenceException;

    for_example

public normal_example
requires (* this is <w,x,y,z,x> and item is x *);
ensures (* \result is 1 *);

prefix

public JMLObjectSequence prefix(\bigint n)
                         throws JMLSequenceException

Return a sequence containing the first n elements in this sequence.

Parameters:

n - the number of elements in the result.

Throws:

JMLSequenceException - if n is negative or greater than the length of the sequence.

See Also:

trailer(), removePrefix(int), subsequence(int, int)

Specifications: (class)pure

public normal_behavior
requires 0 <= n&&n <= this.length;
ensures \result .length == n&&( \forall \bigint i; 0 <= i&&i < n; (\result .itemAt(i) != null ==> \result .itemAt(i) == (this.itemAt(i)))||(\result .itemAt(i) == null ==> this.itemAt(i) == null));
ensures_redundantly (* \result is the same as this, but with the last length-n items removed *);

     also

public exceptional_behavior
requires !(0 <= n&&n <= this.length);
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures !this.containsNull ==> !\result .containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and n is 0 *);
ensures (* \result is <> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and n is 3 *);
ensures (* \result is <a,b,c> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and n is 5 *);
ensures (* \result is <a,b,c,d,e> *);

       also

public normal_example
requires n == this.length;
ensures \result .equals(this);

removePrefix

public JMLObjectSequence removePrefix(\bigint n)
                               throws JMLSequenceException

Return a sequence containing all but the first n elements in this.

Parameters:

n - the number of elements to remove

Throws:

JMLSequenceException - if n is negative or greater than the length of the sequence.

See Also:

header(), prefix(int), subsequence(int, int)

Specifications: (class)pure

public normal_behavior
requires 0 <= n&&n <= this.length;
ensures \result .length == this.length-n&&( \forall \bigint i; n <= i&&i < this.length; (\result .itemAt(i-n) != null&&\result .itemAt(i-n) == (this.itemAt(i)))||(\result .itemAt(i-n) == null&&this.itemAt(i) == null));
ensures_redundantly (* \result is the same as this, but with the first n items removed *);

     also

public exceptional_behavior
requires !(0 <= n&&n <= this.length);
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures !this.containsNull ==> !\result .containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and n is 1 *);
ensures (* \result is <b,c,d,e> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and n is 5 *);
ensures (* \result is <> *);

       also

public normal_example
requires n == this.length;
ensures \result .isEmpty();

removeItemAt

public JMLObjectSequence removeItemAt(\bigint index)
                               throws JMLSequenceException

Return a sequence like this, but without the element at the given zero-based index.

Parameters:

index - the zero-based index into the sequence.

Throws:

JMLSequenceException - if the index is out of range.

See Also:

itemAt(int), removeItemAt(int), prefix(int), removePrefix(int), subsequence(int, int), concat(org.jmlspecs.models.JMLObjectSequence)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= index&&index < this.length();
ensures \result .equals(this.prefix(index).concat(this.removePrefix(index+1)));
ensures_redundantly (* \result is the same as this, but with the item at position index removed *);

     also

public exceptional_behavior
requires !(0 <= index&&index < this.length());
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures !\result .containsNull <== !this.containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and index is 1 *);
ensures (* \result is <a,c,d,e> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and index is 4 *);
ensures (* \result is <a,b,c,d> *);

replaceItemAt

public JMLObjectSequence replaceItemAt(\bigint index,
                                       Object item)
                                throws JMLSequenceException

Return a sequence like this, but with item replacing the element at the given zero-based index.

Parameters:

index - the zero-based index into the sequence.

item - the item to put at index index

Throws:

JMLSequenceException - if the index is out of range.

See Also:

itemAt(int), replaceItemAt(int, java.lang.Object)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= index&&index < this.length();
ensures \result .equals(this.removeItemAt(index).insertBeforeIndex(index,item));
ensures_redundantly (* \result is the same as this, but with item replacing the one at position index *);

     also

public exceptional_behavior
requires !(0 <= index&&index < this.length());
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures item != null ==> \typeof(item) <: \result .elementType;
ensures !\result .containsNull <== !this.containsNull&&item != null;

    for_example

public normal_example
requires (* this is <a,b,c,d,e>, item is x and index is 1 *);
ensures (* \result is <a,x,c,d,e> *);

insertAfterIndex

public JMLObjectSequence insertAfterIndex(\bigint afterThisOne,
                                          Object item)
                                   throws JMLSequenceException,
                                          IllegalStateException

Return a sequence like this, but with item put immediately after the given index.

Parameters:

afterThisOne - a zero-based index into the sequence, or -1.

item - the item to put after index afterThisOne

Returns:

if the index is in range

Throws:

JMLSequenceException - if the index is out of range.

IllegalStateException

See Also:

insertBeforeIndex(int, java.lang.Object), insertFront(java.lang.Object), insertBack(java.lang.Object), removeItemAt(int)

Specifications: non_null (class)pure

public normal_behavior
requires -1 <= afterThisOne&&afterThisOne < this.length;
requires this.length < 2147483647;
ensures \result .equals(this.insertBeforeIndex((int)(afterThisOne+1),item));
ensures_redundantly (* \result is the same sequence as this, but with item inserted after the index "afterThisOne" *);

     also

public exceptional_behavior
requires !(-1 <= afterThisOne&&afterThisOne < this.length);
signals (org.jmlspecs.models.JMLSequenceException) true;

    for_example

public normal_example
requires (* this is <a,b,c> and afterThisOne is 1 and item is d *);
ensures (* \result is <a,b,d,c> *);

       also

public normal_example
requires (* this is <a,b,c> and afterThisOne is -1 and item is d *);
ensures (* \result is <d,a,b,c> *);

insertBeforeIndex

public JMLObjectSequence insertBeforeIndex(\bigint beforeThisOne,
                                           Object item)
                                    throws JMLSequenceException,
                                           IllegalStateException

Return a sequence like this, but with item put immediately before the given index.

Parameters:

beforeThisOne - a zero-based index into the sequence, or the length of this.

item - the item to put before index beforeThisOne

Returns:

if the index is in range

Throws:

JMLSequenceException - if the index is out of range.

IllegalStateException

See Also:

insertAfterIndex(int, java.lang.Object), insertFront(java.lang.Object), insertBack(java.lang.Object), removeItemAt(int)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= beforeThisOne&&beforeThisOne <= this.length;
requires this.length < 2147483647;
ensures \result .equals(this.prefix(beforeThisOne).concat(new org.jmlspecs.models.JMLObjectSequence(item)).concat(this.removePrefix(beforeThisOne)));

     also

public exceptional_behavior
requires !(0 <= beforeThisOne&&beforeThisOne <= this.length);
signals (org.jmlspecs.models.JMLSequenceException) true;

subsequence

public JMLObjectSequence subsequence(\bigint from,
                                     \bigint to)
                              throws JMLSequenceException

Returns a subsequence of this containing the elements beginning with index from (inclusive) and ending with index to (exclusive).

Parameters:

from - the inclusive, zero-based element of the first element in the subsequence.

to - the zero-based element of the first element that should not be in the subsequence.

Throws:

JMLSequenceException - if (from < 0 or from > to or to > length of this.

See Also:

prefix(int), removePrefix(int), header(), trailer(), concat(org.jmlspecs.models.JMLObjectSequence)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= from&&from <= to&&to <= this.length();
ensures \result .equals(this.removePrefix(from).prefix((int)(to-from)));
ensures_redundantly (* \result contains the elements of this beginning with index from (inclusive) and ending with index to (exclusive) *)&&\result .length() == to-from;

     also

public exceptional_behavior
requires !(0 <= from&&from <= to&&to <= this.length());
signals (org.jmlspecs.models.JMLSequenceException) true;

    implies_that

ensures !\result .containsNull <== !this.containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and from is 1 and to is 3 *);
ensures (* \result is <b,c> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and from is 0 and to is 3 *);
ensures (* \result is <a,b,c> *);

       also

public normal_example
requires from == to;
ensures \result .isEmpty();

bigintToBigInteger

public static BigInteger bigintToBigInteger(\bigint biValue)

Specifications: pure

bigIntegerToBigint

public static \bigint bigIntegerToBigint(BigInteger oBi)

Specifications: pure

public normal_behavior
requires oBi.equals(java.math.BigInteger.ZERO);
ensures \result == 0;

singleton

public static JMLObjectSequence singleton(Object e)

Return the singleton sequence containing the given element.

See Also:

JMLObjectSequence(Object)

Specifications: pure non_null

public normal_behavior
assignable \nothing;
ensures \result != null&&\result .equals(new org.jmlspecs.models.JMLObjectSequence(e));

convertFrom

public static JMLObjectSequence convertFrom(non_null Object[] a)

Return the sequence containing all the elements in the given array in the same order as the elements appear in the array.

Specifications: pure non_null

public normal_behavior
requires a != null;
assignable \nothing;
ensures \result != null&&\result .size() == a.length&&( \forall int i; 0 <= i&&i < a.length; (\result .itemAt(i) == null ? a[i] == null : \result .itemAt(i) == a[i]));

convertFrom

public static JMLObjectSequence convertFrom(non_null Object[] a,
                                            int size)

Return the sequence containing the first 'size' elements in the given array in the same order as the elements appear in the array.

Specifications: pure non_null

public normal_behavior
requires a != null&&0 <= size&&size < a.length;
assignable \nothing;
ensures \result != null&&\result .size() == size&&( \forall int i; 0 <= i&&i < size; (\result .itemAt(i) == null ? a[i] == null : \result .itemAt(i) == a[i]));

    implies_that

requires size < a.length;

convertFrom

public static JMLObjectSequence convertFrom(non_null Collection c)
                                     throws ClassCastException

Return the sequence containing all the object in the given collection in the same order as the elements appear in the collection.

Throws:

ClassCastException - if some element in c is not an instance of Object.

See Also:

containsAll(java.util.Collection)

Specifications: pure non_null

public normal_behavior
requires c != null&&c.elementType <: \type(java.lang.Object);
requires c.size() < 2147483647;
assignable \nothing;
ensures \result != null&&\result .size() == c.size()&&( \forall java.lang.Object x; ; c.contains(x) <==> \result .has(x))&&(* the elements in \result are in the same order as c *);

     also

public exceptional_behavior
requires c != null&&( \exists java.lang.Object o; c.contains(o); !(o instanceof java.lang.Object));
assignable \nothing;
signals_only java.lang.ClassCastException;

convertFrom

public static JMLObjectSequence convertFrom(non_null JMLCollection c)
                                     throws ClassCastException

Return the sequence containing all the object in the given JMLCollection in the same order as the elements appear in the collection.

Throws:

ClassCastException - if some element in c is not an instance of Object.

Specifications: pure non_null

public normal_behavior
requires c != null&&c.elementType <: \type(java.lang.Object);
requires c.size() < 2147483647;
assignable \nothing;
ensures \result != null&&( \forall java.lang.Object x; ; c.has(x) <==> \result .has(x))&&(* the elements in \result are in the same order as c *);
ensures_redundantly \result .size() == c.size();

     also

public exceptional_behavior
requires c != null&&( \exists java.lang.Object o; c.has(o); !(o instanceof java.lang.Object));
assignable \nothing;
signals_only java.lang.ClassCastException;

itemAt

public Object itemAt(int i)
              throws JMLSequenceException

Return the element at the given zero-based index.

Parameters:

i - the zero-based index into the sequence.

Throws:

JMLSequenceException - if the index i is out of range.

See Also:

get(int), has(Object), count(Object), #itemAt(\bigint)

Specifications: (class)pure

public normal_behavior
requires 0 <= i&&i < this.int_size();
ensures (* \result == null, if the ith element of this is null; otherwise, \result "==" the ith element of this *);
ensures \result != null ==> \typeof(\result ) <: this.elementType;
ensures !this.containsNull ==> \result != null;

     also

public exceptional_behavior
requires !(0 <= i&&i < this.int_size());
signals_only org.jmlspecs.models.JMLSequenceException;

    for_example

public normal_example
requires (* this is <w,x,y,z> and i is 0 *);
ensures (* \result is w *);

       also

public normal_example
requires (* this is <w,x,y,z> and i is 3 *);
ensures (* \result is z *);

get

public Object get(int i)
           throws IndexOutOfBoundsException

Return the element at the given zero-based index; a synonym for itemAt(int).

Parameters:

i - the zero-based index into the sequence.

Throws:

IndexOutOfBoundsException - if the index i is out of range.

See Also:

itemAt(int)

Specifications: (class)pure

public normal_behavior
requires 0 <= i&&i < this.length;
ensures (* \result == null, if the ith element of this is null; otherwise, \result "==" the ith element of this *);

     also

public exceptional_behavior
requires !(0 <= i&&i < this.length);
signals_only java.lang.IndexOutOfBoundsException;

    implies_that

ensures \result != null ==> \typeof(\result ) <: this.elementType;
ensures !this.containsNull ==> \result != null;

int_size

public int int_size()

Tells the number of elements in the sequence; a synonym for #length.

Specified by:

int_size in interface JMLCollection

See Also:

#length(), isEmpty()

Specifications: (class)pure

     also

protected normal_behavior
requires this.size() <= 2147483647;
ensures \result == this.size();

    for_example

public normal_example
requires (* this is <a,b,c,d> *);
ensures \result == 4;

       also

public normal_example
requires (* this is <> *);
ensures \result == 0;

Specifications inherited from overridden method in interface JMLCollection:
       pure

public normal_behavior
requires this.size() <= 2147483647;
ensures \result == this.size();

int_length

public int int_length()

Tells the number of elements in the sequence; a synonym for #size.

See Also:

int_size()

Specifications: (class)pure

public normal_behavior
requires this.size() <= 2147483647;
ensures \result == this.size();

    implies_that

ensures \result >= 0;

count

public int count(Object item)

Tells the number of times a given element occurs in the sequence.

See Also:

has(Object), itemAt(int)

Specifications: (class)pure

public normal_behavior
requires item != null;
ensures \result == ( \num_of int i; 0 <= i&&i < this.int_length(); this.itemAt(i) != null&&this.itemAt(i) == item);

     also

public normal_behavior
requires item == null;
ensures \result == ( \num_of int i; 0 <= i&&i < this.int_length(); this.itemAt(i) == null);

    implies_that

ensures \result >= 0;

    for_example

public normal_example
requires (* this is <a,b,c,d,c> and item is c *);
ensures \result == 2;

       also

public normal_example
requires (* this is <a,b,c,d,a> and item is q *);
ensures \result == 0;

has

public boolean has(Object elem)

Tells whether the given element is "==" to an element in the sequence.

Specified by:

has in interface JMLCollection

See Also:

count(Object)

Specifications: (class)pure

     also

public normal_behavior

{|

requires elem != null;
ensures \result <==> ( \exists int i; 0 <= i&&i < this.int_length(); this.itemAt(i) == elem);

also

requires elem == null;
ensures \result <==> ( \exists int i; 0 <= i&&i < this.int_length(); this.itemAt(i) == null);

|}

    for_example

public normal_example
requires (* this is <w,x,y,z> and elem is x *);
ensures (* \result is true *);

       also

public normal_example
requires this.isEmpty();
ensures !\result ;

Specifications inherited from overridden method has(Object elem) in interface JMLCollection:
       pure

public normal_behavior
ensures (* \result <==> elem is equal to one of the elements in the collection. *);
ensures_redundantly !this.containsNull&&elem == null ==> !\result ;
ensures_redundantly elem != null&&!(\typeof(elem) <: this.elementType) ==> !\result ;

containsAll

public boolean containsAll(non_null Collection c)

Tell whether, for each element in the given collection, there is a "==" element in this sequence.

Parameters:

c - the collection whose elements are sought.

Specifications: (class)pure

public normal_behavior
requires c != null;
ensures \result <==> ( \forall java.lang.Object o; c.contains(o); this.has(o));

isPrefix

public boolean isPrefix(non_null JMLObjectSequence s2)

Tells whether the elements of the this sequence occur, in order, at the beginning of the given sequence, using "==" for comparisons.

See Also:

isProperPrefix(org.jmlspecs.models.JMLObjectSequence), isSuffix(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> this.int_length() <= s2.int_length()&&( \forall int i; 0 <= i&&i < this.int_length(); (s2.itemAt(i) != null&&s2.itemAt(i) == (this.itemAt(i)))||(s2.itemAt(i) == null&&this.itemAt(i) == null));

    for_example

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c,d> and s2 is <a,b,c> *);
ensures (* \result is false *);

isProperPrefix

public boolean isProperPrefix(non_null JMLObjectSequence s2)

Tells whether this sequence is shorter than the given sequence, and also if the elements of this sequence occur, in order, at the beginning of the given sequence, using "==" for comparisons.

See Also:

isPrefix(org.jmlspecs.models.JMLObjectSequence), isProperSuffix(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> this.isPrefix(s2)&&!this.equals(s2);

    for_example

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c> *);
ensures (* \result is false *);

isSuffix

public boolean isSuffix(non_null JMLObjectSequence s2)

Tells whether the elements of this sequence occur, in order, at the end of the given sequence, using "==" for comparisons.

See Also:

isProperSuffix(org.jmlspecs.models.JMLObjectSequence), isPrefix(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> this.int_length() <= s2.int_length()&&this.equals(s2.removePrefix(s2.int_length()-this.int_length()));

    for_example

public normal_example
requires (* this is <b,c,d> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c,d> *);
ensures (* \result is false *);

       also

public normal_example
requires (* this is <> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

isProperSuffix

public boolean isProperSuffix(non_null JMLObjectSequence s2)

Tells whether the this sequence is shorter than the given object, and also if the elements of this sequence occur, in order, at the end of the given sequence, using "==" for comparisons.

See Also:

isSuffix(org.jmlspecs.models.JMLObjectSequence), isProperPrefix(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> this.isSuffix(s2)&&!this.equals(s2);

equals

public boolean equals(nullable Object obj)

Test whether this object's value is equal to the given argument.

Specified by:

equals in interface JMLType

Overrides:

equals in class Object

See Also:

isSuffix(org.jmlspecs.models.JMLObjectSequence), int_size()

Specifications: pure

     also

public normal_behavior
requires obj != null&&obj instanceof org.jmlspecs.models.JMLObjectSequence;
ensures \result <==> this.isPrefix((org.jmlspecs.models.JMLObjectSequence)obj)&&((org.jmlspecs.models.JMLObjectSequence)obj).isPrefix(this);
ensures_redundantly \result ==> this.containsNull == ((org.jmlspecs.models.JMLObjectSequence)obj).containsNull;

     also

public normal_behavior
requires obj == null||!(obj instanceof org.jmlspecs.models.JMLObjectSequence);
ensures !\result ;

Specifications inherited from overridden method equals(Object obj) in class Object:
       pure

public normal_behavior
requires obj != null;
ensures (* \result is true when obj is "equal to" this object *);

     also

public normal_behavior
requires this == obj;
ensures \result ;

     also

public code normal_behavior
requires obj != null;
ensures \result <==> this == obj;

     also

diverges false;
ensures obj == null ==> !\result ;

Specifications inherited from overridden method equals(Object ob2) in interface JMLType:
       pure

     also

public normal_behavior
ensures \result ==> ob2 != null&&(* ob2 is not distinguishable from this, except by using mutation or == *);

    implies_that

public normal_behavior

{|

requires ob2 != null&&ob2 instanceof org.jmlspecs.models.JMLType;
ensures ((org.jmlspecs.models.JMLType)ob2).equals(this) == \result ;

also

requires ob2 == this;
ensures \result <==> true;

|}

hashCode

public int hashCode()

Return a hash code for this object.

Specified by:

hashCode in interface JMLType

Overrides:

hashCode in class Object

Specifications: (class)pure

Specifications inherited from overridden method in class Object:

public behavior
assignable objectState;
ensures (* \result is a hash code for this object *);

     also

public code normal_behavior
assignable \nothing;

Specifications inherited from overridden method in interface JMLType:
       pure

isEmpty

public boolean isEmpty()

Tells whether this sequence is empty.

See Also:

int_size(), int_length()

Specifications: pure

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

indexOf

public int indexOf(Object item)
            throws JMLSequenceException

Return the zero-based index of the first occurrence of the given element in the sequence, if there is one

Parameters:

item - the Object sought in this.

Returns:

the first index at which item occurs.

Throws:

JMLSequenceException - if item is not a member of the sequence.

See Also:

itemAt(int)

Specifications: (class)pure

public normal_behavior
requires this.has(item);

{|

requires item != null;
ensures this.itemAt(\result ) == item&&( \forall int i; 0 <= i&&i < \result ; !(this.itemAt(i) == item));
ensures_redundantly (* \result is the first index at which item occurs in this *);

also

requires item == null;
ensures this.itemAt(\result ) == null&&( \forall int i; 0 <= i&&i < \result ; this.itemAt(i) != null);

|}

     also

public exceptional_behavior
requires !this.has(item);
signals_only org.jmlspecs.models.JMLSequenceException;

    for_example

public normal_example
requires (* this is <w,x,y,z,x> and item is x *);
ensures (* \result is 1 *);

first

public Object first()
             throws JMLSequenceException

Return the first element in this sequence.

Throws:

JMLSequenceException - if the sequence is empty.

See Also:

itemAt(int), last(), trailer(), header()

Specifications: pure

public normal_behavior
requires this.int_length() > 0;

{|

requires this.itemAt(0) != null;
ensures \result == (this.itemAt(0));

also

requires this.itemAt(0) == null;
ensures \result == null;

|}

     also

public exceptional_behavior
requires this.int_length() == 0;
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

public normal_behavior
requires this.int_length() > 0;
ensures \result != null ==> \typeof(\result ) <: this.elementType;
ensures !this.containsNull ==> \result != null;

    for_example

public normal_example
requires (* this is <b,c,d> *);
ensures (* \result is b *);

last

public Object last()
            throws JMLSequenceException

Return the last element in this sequence.

Throws:

JMLSequenceException - if the sequence is empty.

See Also:

itemAt(int), first(), header(), trailer()

Specifications: (class)pure

public normal_behavior
requires this.int_length() >= 1;

{|

requires this.itemAt((int)(this.int_length()-1)) != null;
ensures \result == (this.itemAt((int)(this.int_length()-1)));

also

requires this.itemAt((int)(this.int_length()-1)) == null;
ensures \result == null;

|}

     also

public exceptional_behavior
requires this.int_length() == 0;
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

public normal_behavior
requires this.int_length() >= 1;
ensures \result != null ==> \typeof(\result ) <: this.elementType;
ensures !this.containsNull ==> \result != null;

    for_example

public normal_example
requires (* this is <b,c,d> *);
ensures (* \result is d *);

isSubsequence

public boolean isSubsequence(non_null JMLObjectSequence s2)

Tells whether this sequence is a subsequence of the given sequence.

Parameters:

s2 - the sequence to search for within this sequence.

Returns:

whether the elements of this occur (in order) within s2.

See Also:

isProperSubsequence(org.jmlspecs.models.JMLObjectSequence), isSupersequence(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> this.int_length() <= s2.int_length()&&( \exists int i; 0 <= i&&i < s2.int_length()-this.int_length()+1; this.isPrefix(s2.removePrefix(i)));

    for_example

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c,d> and s2 is <a,b,c> *);
ensures (* \result is false *);

isProperSubsequence

public boolean isProperSubsequence(non_null JMLObjectSequence s2)

Tells whether this sequence is strictly shorter than the given sequence and a subsequence of it.

Parameters:

s2 - the sequence to search for within this sequence.

Returns:

whether the elements of s2 occur (in order) within this.

See Also:

isSubsequence(org.jmlspecs.models.JMLObjectSequence), isProperSupersequence(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> this.isSubsequence(s2)&&!this.equals(s2);

    for_example

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c,d> *);
ensures (* \result is true *);

       also

public normal_example
requires (* this is <a,b,c> and s2 is <a,b,c> *);
ensures (* \result is false *);

       also

public normal_example
requires (* this is <> and s2 is <a,b,c,d> *);
ensures (* \result is false *);

isSupersequence

public boolean isSupersequence(non_null JMLObjectSequence s2)

Tells whether the given sequence is a supersequence of this sequence.

Parameters:

s2 - the sequence to search within for this sequence.

Returns:

whether the elements of this occur (in order) within s2.

See Also:

isProperSubsequence(org.jmlspecs.models.JMLObjectSequence), isSubsequence(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> s2.isSubsequence(this);

isProperSupersequence

public boolean isProperSupersequence(non_null JMLObjectSequence s2)

Tells whether the given sequence is both longer than and a supersequence of this sequence.

Parameters:

s2 - the sequence to search within for this sequence.

Returns:

whether the elements of this occur (in order) within s2.

See Also:

isSupersequence(org.jmlspecs.models.JMLObjectSequence), isProperSubsequence(org.jmlspecs.models.JMLObjectSequence)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> s2.isProperSubsequence(this);

isInsertionInto

public boolean isInsertionInto(non_null JMLObjectSequence s2,
                               Object elem)

Tells whether this sequence is the result of inserting the given element once into the given sequence. That is, this sequence is exactly one element longer than the given sequence, and its elements are in the same order, except for the insertion of the given element.

Parameters:

s2 - the shorter sequence, which we see if the elem is inserted into

elem - the given element

Returns:

whether the elements of s2 occur in order in this sequence, with the insertion of elem somewhere.

See Also:

isDeletionFrom(org.jmlspecs.models.JMLObjectSequence, java.lang.Object), isProperSupersequence(org.jmlspecs.models.JMLObjectSequence), isProperSubsequence(org.jmlspecs.models.JMLObjectSequence), subsequence(int, int)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> ( \exists int i; 0 <= i&&i < this.int_length(); this.itemAt(i) == elem&&this.subsequence(0,i).concat(this.subsequence((int)(i+1),this.int_length())).equals(s2));
ensures_redundantly \result ==> this.int_length() == s2.int_length()+1;
ensures_redundantly \result ==> this.has(elem);
ensures_redundantly \result <==> s2.isDeletionFrom(this,elem);

isDeletionFrom

public boolean isDeletionFrom(non_null JMLObjectSequence s2,
                              Object elem)

Tells whether this sequence is the result of deleting the given element once from the given sequence. That is, this sequence is exactly one element shorter than the given sequence, and its elements are in the same order, except for the deletion of the given element from the given sequence.

Parameters:

s2 - the longer sequence, in which we see if the elem is deleted from

elem - the given element

Returns:

whether the elements of s2 occur in order in this sequence, with the deletion of elem somewhere.

See Also:

isInsertionInto(org.jmlspecs.models.JMLObjectSequence, java.lang.Object), isProperSupersequence(org.jmlspecs.models.JMLObjectSequence), isProperSubsequence(org.jmlspecs.models.JMLObjectSequence), subsequence(int, int)

Specifications: (class)pure

public normal_behavior
requires s2 != null;
ensures \result <==> ( \exists int i; 0 <= i&&i < s2.int_length(); s2.itemAt(i) == elem&&this.equals(s2.removeItemAt(i)));
ensures_redundantly \result ==> this.int_length()+1 == s2.int_length();
ensures_redundantly \result ==> s2.has(elem);
ensures_redundantly \result <==> s2.isInsertionInto(this,elem);

clone

public Object clone()

Return a clone of this object. This method does not clone the elements of the sequence.

Specified by:

clone in interface JMLType

Overrides:

clone in class Object

Specifications: non_null (class)pure

     also

public normal_behavior
ensures \result != null&&\result instanceof org.jmlspecs.models.JMLObjectSequence&&((org.jmlspecs.models.JMLObjectSequence)\result ).equals(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]);

Specifications inherited from overridden method in interface JMLType:
       pure

     also

public normal_behavior
ensures \result != null;
ensures \result instanceof org.jmlspecs.models.JMLType;
ensures ((org.jmlspecs.models.JMLType)\result ).equals(this);

    implies_that

ensures \result != null&&\typeof(\result ) <: \type(org.jmlspecs.models.JMLType);

prefix

public JMLObjectSequence prefix(int n)
                         throws JMLSequenceException

Return a sequence containing the first n elements in this sequence.

Parameters:

n - the number of elements in the result.

Throws:

JMLSequenceException - if n is negative or greater than the length of the sequence.

See Also:

trailer(), removePrefix(int), subsequence(int, int)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= n&&n <= this.length;
ensures \result .length == n&&( \forall int i; 0 <= i&&i < n; (\result .itemAt(i) != null ==> \result .itemAt(i) == (this.itemAt(i)))||(\result .itemAt(i) == null ==> this.itemAt(i) == null));
ensures_redundantly (* \result is the same as this, but with the last length-n items removed *);

     also

public exceptional_behavior
requires !(0 <= n&&n <= this.length);
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures !this.containsNull ==> !\result .containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and n is 0 *);
ensures (* \result is <> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and n is 3 *);
ensures (* \result is <a,b,c> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and n is 5 *);
ensures (* \result is <a,b,c,d,e> *);

       also

public normal_example
requires n == this.length;
ensures \result .equals(this);

removePrefix

public JMLObjectSequence removePrefix(int n)
                               throws JMLSequenceException

Return a sequence containing all but the first n elements in this.

Parameters:

n - the number of elements to remove

Throws:

JMLSequenceException - if n is negative or greater than the length of the sequence.

See Also:

header(), prefix(int), subsequence(int, int)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= n&&n <= this.length;
ensures \result .length == this.length-n&&( \forall \bigint i; n <= i&&i < this.length; (\result .itemAt((int)(i-n)) != null&&\result .itemAt((int)(i-n)) == (this.itemAt(i)))||(\result .itemAt((int)(i-n)) == null&&this.itemAt(i) == null));
ensures_redundantly (* \result is the same as this, but with the first n items removed *);

     also

public exceptional_behavior
requires !(0 <= n&&n <= this.length);
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures !this.containsNull ==> !\result .containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and n is 1 *);
ensures (* \result is <b,c,d,e> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and n is 5 *);
ensures (* \result is <> *);

       also

public normal_example
requires n == this.length;
ensures \result .isEmpty();

concat

public JMLObjectSequence concat(non_null JMLObjectSequence s2)

Return a sequence that is the concatenation of this with the given sequence.

Parameters:

s2 - the sequence to place at the end of this sequence in the result.

Returns:

the concatenation of this sequence and s2.

Specifications: non_null (class)pure

public normal_behavior
requires s2 != null;
ensures \result .int_length() == this.int_length()+s2.int_length()&&( \forall int i; 0 <= i&&i < this.int_length(); (\result .itemAt(i) != null&&\result .itemAt(i) == (this.itemAt(i)))||(\result .itemAt(i) == null&&this.itemAt(i) == null))&&( \forall int i; 0 <= i&&i < s2.int_length(); (\result .itemAt((int)(this.int_length()+i)) != null&&\result .itemAt((int)(this.int_length()+i)) == (s2.itemAt(i)))||(\result .itemAt((int)(this.int_length()+i)) == null&&s2.itemAt(i) == null));
ensures_redundantly (* \result is the concatenation of this followed by s2 *);

    implies_that

ensures this.containsNull||s2.containsNull <==> \result .containsNull;

    for_example

public normal_example
requires (* this is <a,b> and s2 is <c,d,e> *);
ensures (* \result is <a,b,c,d,e> *);

reverse

public JMLObjectSequence reverse()

Return a sequence that is the reverse of this sequence.

Returns:

the reverse of this sequence.

Specifications: non_null (class)pure

public normal_behavior
old int len = this.int_length();
ensures \result .int_length() == len&&( \forall int i; 0 <= i&&i < len; (\result .itemAt((int)(len-i-1)) != null&&\result .itemAt((int)(len-i-1)) == (this.itemAt(i)))||(\result .itemAt((int)(len-i-1)) == null&&this.itemAt(i) == null));
ensures_redundantly (* \result has the same elements but with the items arranged in the reverse order *);

    implies_that

ensures this.elementType == \result .elementType;
ensures this.containsNull <==> \result .containsNull;

removeItemAt

public JMLObjectSequence removeItemAt(int index)
                               throws JMLSequenceException

Return a sequence like this, but without the element at the given zero-based index.

Parameters:

index - the zero-based index into the sequence.

Throws:

JMLSequenceException - if the index is out of range.

See Also:

itemAt(int), removeItemAt(int), prefix(int), removePrefix(int), subsequence(int, int), concat(org.jmlspecs.models.JMLObjectSequence)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= index&&index < this.int_length();
ensures \result .equals(this.prefix(index).concat(this.removePrefix((int)(index+1))));
ensures_redundantly (* \result is the same as this, but with the item at position index removed *);

     also

public exceptional_behavior
requires !(0 <= index&&index < this.int_length());
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures !\result .containsNull <== !this.containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and index is 1 *);
ensures (* \result is <a,c,d,e> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and index is 4 *);
ensures (* \result is <a,b,c,d> *);

replaceItemAt

public JMLObjectSequence replaceItemAt(int index,
                                       Object item)
                                throws JMLSequenceException

Return a sequence like this, but with item replacing the element at the given zero-based index.

Parameters:

index - the zero-based index into the sequence.

item - the item to put at index index

Throws:

JMLSequenceException - if the index is out of range.

See Also:

itemAt(int), replaceItemAt(int, java.lang.Object)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= index&&index < this.int_length();
ensures \result .equals(this.removeItemAt(index).insertBeforeIndex(index,item));
ensures_redundantly (* \result is the same as this, but with item replacing the one at position index *);

     also

public exceptional_behavior
requires !(0 <= index&&index < this.int_length());
signals_only org.jmlspecs.models.JMLSequenceException;

    implies_that

ensures item != null ==> \typeof(item) <: \result .elementType;
ensures !\result .containsNull <== !this.containsNull&&item != null;

    for_example

public normal_example
requires (* this is <a,b,c,d,e>, item is x and index is 1 *);
ensures (* \result is <a,x,c,d,e> *);

header

public JMLObjectSequence header()
                         throws JMLSequenceException

Return a sequence containing all but the last element in this.

Throws:

JMLSequenceException - if this is empty.

See Also:

prefix(int), first(), last(), trailer(), subsequence(int, int)

Specifications: non_null (class)pure

public normal_behavior
requires this.int_length() >= 1;
ensures \result .equals(this.removeItemAt((int)(this.int_length()-1)));
ensures_redundantly \result .int_length() == this.int_length()-1&&(* \result is like this, but without the last item *);

     also

public exceptional_behavior
requires this.int_length() == 0;
signals (org.jmlspecs.models.JMLSequenceException) true;

    implies_that

ensures !\result .containsNull <== !this.containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d> *);
ensures (* \result is <a,b,c> *);

trailer

public JMLObjectSequence trailer()
                          throws JMLSequenceException

Return a sequence containing all but the first element in this.

Throws:

JMLSequenceException - if this is empty.

See Also:

removePrefix(int), last(), first(), header(), subsequence(int, int)

Specifications: pure non_null

public normal_behavior
requires this.int_length() >= 1;
ensures \result .equals(this.removePrefix(1));
ensures_redundantly \result .int_length() == this.int_length()-1&&(* \result is like this, but without the first item *);

     also

public exceptional_behavior
requires this.int_length() == 0;
signals (org.jmlspecs.models.JMLSequenceException) true;

    implies_that

ensures !\result .containsNull <== !this.containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d> *);
ensures (* \result is <b,c,d> *);

insertAfterIndex

public JMLObjectSequence insertAfterIndex(int afterThisOne,
                                          Object item)
                                   throws JMLSequenceException,
                                          IllegalStateException

Return a sequence like this, but with item put immediately after the given index.

Parameters:

afterThisOne - a zero-based index into the sequence, or -1.

item - the item to put after index afterThisOne

Returns:

if the index is in range

Throws:

JMLSequenceException - if the index is out of range.

IllegalStateException

See Also:

insertBeforeIndex(int, java.lang.Object), insertFront(java.lang.Object), insertBack(java.lang.Object), removeItemAt(int)

Specifications: non_null (class)pure

public normal_behavior
requires -1 <= afterThisOne&&afterThisOne < this.length;
requires this.length < 2147483647;
ensures \result .equals(this.insertBeforeIndex((int)(afterThisOne+1),item));
ensures_redundantly (* \result is the same sequence as this, but with item inserted after the index "afterThisOne" *);

     also

public exceptional_behavior
requires !(-1 <= afterThisOne&&afterThisOne < this.length);
signals (org.jmlspecs.models.JMLSequenceException) true;

    for_example

public normal_example
requires (* this is <a,b,c> and afterThisOne is 1 and item is d *);
ensures (* \result is <a,b,d,c> *);

       also

public normal_example
requires (* this is <a,b,c> and afterThisOne is -1 and item is d *);
ensures (* \result is <d,a,b,c> *);

insertBeforeIndex

public JMLObjectSequence insertBeforeIndex(int beforeThisOne,
                                           Object item)
                                    throws JMLSequenceException,
                                           IllegalStateException

Return a sequence like this, but with item put immediately before the given index.

Parameters:

beforeThisOne - a zero-based index into the sequence, or the length of this.

item - the item to put before index beforeThisOne

Returns:

if the index is in range

Throws:

JMLSequenceException - if the index is out of range.

IllegalStateException

See Also:

insertAfterIndex(int, java.lang.Object), insertFront(java.lang.Object), insertBack(java.lang.Object), removeItemAt(int)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= beforeThisOne&&beforeThisOne <= this.length;
requires this.length < 2147483647;
ensures \result .equals(this.prefix(beforeThisOne).concat(new org.jmlspecs.models.JMLObjectSequence(item)).concat(this.removePrefix(beforeThisOne)));

     also

public exceptional_behavior
requires !(0 <= beforeThisOne&&beforeThisOne <= this.length);
signals (org.jmlspecs.models.JMLSequenceException) true;

     also

public model_program { ... }

insertBack

public JMLObjectSequence insertBack(Object item)
                             throws IllegalStateException

Return a sequence like this, but with the given item put an the end.

Parameters:

item - the item to put at the end of the result.

Returns:

a sequence the elements of this sequence followed by item.

Throws:

IllegalStateException

See Also:

insertAfterIndex(int, java.lang.Object), insertBeforeIndex(int, java.lang.Object), insertFront(java.lang.Object), removeItemAt(int), header(), last()

Specifications: non_null (class)pure

public normal_behavior
requires this.int_length() < 2147483647;
ensures \result .equals(this.insertBeforeIndex(this.int_length(),item));
ensures_redundantly \result .int_length() == this.int_length()+1&&this.isProperPrefix(\result );
ensures_redundantly (* \result is the same sequence as this, but with item inserted at the back, after index int_length() - 1 *);

    for_example

public normal_example
requires (* this is <a,b,c> and item is d *);
ensures (* \result is <a,b,c,d> *);

insertFront

public JMLObjectSequence insertFront(Object item)
                              throws IllegalStateException

Return a sequence like this, but with the given item put an the front.

Parameters:

item - the item to put at the front of the result.

Returns:

a sequence with item followed by the elements of this sequence.

Throws:

IllegalStateException

See Also:

insertAfterIndex(int, java.lang.Object), insertBeforeIndex(int, java.lang.Object), insertBack(java.lang.Object), removeItemAt(int), trailer(), first()

Specifications: pure non_null

public normal_behavior
requires this.int_length() < 2147483647;
ensures \result .equals(this.insertBeforeIndex(0,item));
ensures_redundantly \result .int_length() == this.int_length()+1&&\result .trailer().equals(this);
ensures_redundantly (* \result is the same sequence as this, but with item inserted at the front, before index 0 *);

    for_example

public normal_example
requires (* this is <a,b,c> and item is d *);
ensures (* \result is <d,a,b,c> *);

subsequence

public JMLObjectSequence subsequence(int from,
                                     int to)
                              throws JMLSequenceException

Returns a subsequence of this containing the elements beginning with index from (inclusive) and ending with index to (exclusive).

Parameters:

from - the inclusive, zero-based element of the first element in the subsequence.

to - the zero-based element of the first element that should not be in the subsequence.

Throws:

JMLSequenceException - if (from < 0 or from > to or to > length of this.

See Also:

prefix(int), removePrefix(int), header(), trailer(), concat(org.jmlspecs.models.JMLObjectSequence)

Specifications: non_null (class)pure

public normal_behavior
requires 0 <= from&&from <= to&&to <= this.int_length();
ensures \result .equals(this.removePrefix(from).prefix((int)(to-from)));
ensures_redundantly (* \result contains the elements of this beginning with index from (inclusive) and ending with index to (exclusive) *)&&\result .int_length() == to-from;

     also

public exceptional_behavior
requires !(0 <= from&&from <= to&&to <= this.int_length());
signals (org.jmlspecs.models.JMLSequenceException) true;

    implies_that

ensures !\result .containsNull <== !this.containsNull;

    for_example

public normal_example
requires (* this is <a,b,c,d,e> and from is 1 and to is 3 *);
ensures (* \result is <b,c> *);

       also

public normal_example
requires (* this is <a,b,c,d,e> and from is 0 and to is 3 *);
ensures (* \result is <a,b,c> *);

       also

public normal_example
requires from == to;
ensures \result .isEmpty();

toBag

public JMLObjectBag toBag()

Return a new JMLObjectBag containing all the elements of this.

See Also:

toSet(), toArray()

Specifications: non_null (class)pure

public normal_behavior
ensures \result != null&&( \forall int i; 0 <= i&&i < this.int_length(); \result .count(this.itemAt(i)) == this.count(this.itemAt(i)));

toSet

public JMLObjectSet toSet()

Return a new JMLObjectSet containing all the elements of this.

See Also:

toBag(), toArray()

Specifications: non_null (class)pure

public normal_behavior
ensures \result != null&&( \forall java.lang.Object o; ; \result .has(o) == this.has(o));

toArray

public Object[] toArray()

Return a new array containing all the elements of this in order.

See Also:

toSet(), toBag()

Specifications: non_null (class)pure

public normal_behavior
ensures \result != null&&\result .length == this.int_length()&&( \forall int i; 0 <= i&&i < this.int_length(); (\result [i] == null ==> this.itemAt(i) == null)&&(\result [i] != null ==> \result [i] == (this.itemAt(i))));

elements

public JMLObjectSequenceEnumerator elements()

Return a enumerator for this.

See Also:

iterator(), #itemAt()

Specifications: non_null (class)pure

public normal_behavior
ensures \fresh(\result )&&(* \result is an enumerator for this *);

iterator

public JMLIterator iterator()

Returns an iterator over this sequence.

Specified by:

iterator in interface JMLCollection

See Also:

elements()

Specifications: non_null (class)pure

     also

public normal_behavior
ensures \fresh(\result )&&\result .equals(new org.jmlspecs.models.JMLEnumerationToIterator(this.elements()));

Specifications inherited from overridden method in interface JMLCollection:
       pure non_null

public normal_behavior
ensures \fresh(\result )&&\result .elementType == this.elementType;
ensures !this.containsNull ==> !\result .returnsNull;

toString

public String toString()

Return a string representation of this object.

Overrides:

toString in class Object

Specifications: non_null (class)pure

     also

public normal_behavior
ensures (* \result is a string representation of this *);

Specifications inherited from overridden method in class Object:
       non_null

public normal_behavior
assignable objectState;
ensures \result != null&&\result .equals(this.theString);
ensures (* \result is a string representation of this object *);

     also

public code normal_behavior
assignable \nothing;
ensures \result != null&&(* \result is the instance's class name, followed by an @, followed by the instance's hashcode in hex *);

     also

public code model_program { ... }

    implies_that

assignable objectState;
ensures \result != null;