Class SequencesComparator<T>
- Type Parameters:
T- the type of elements in the lists.
The two sequences can hold any object type, as only the equals
method is used to compare the elements of the sequences. It is guaranteed
that the comparisons will always be done as o1.equals(o2) where
o1 belongs to the first sequence and o2 belongs to
the second sequence. This can be important if subclassing is used for some
elements in the first sequence and the equals method is
specialized.
Comparison can be seen from two points of view: either as giving the smallest
modification allowing to transform the first sequence into the second one, or
as giving the longest sequence which is a subsequence of both initial
sequences. The equals method is used to compare objects, so any
object can be put into sequences. Modifications include deleting, inserting
or keeping one object, starting from the beginning of the first sequence.
This class implements the comparison algorithm, which is the very efficient
algorithm from Eugene W. Myers
An O(ND) Difference Algorithm and Its Variations. This algorithm produces
the shortest possible
edit script
containing all the
commands
needed to transform the first sequence into the second one.
- Since:
- 4.0
- See Also:
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Constructor Summary
Constructors -
Method Summary
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Constructor Details
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SequencesComparator
Simple constructor.Creates a new instance of SequencesComparator using a
DefaultEquator.It is guaranteed that the comparisons will always be done as
o1.equals(o2)whereo1belongs to the first sequence ando2belongs to the second sequence. This can be important if subclassing is used for some elements in the first sequence and theequalsmethod is specialized.- Parameters:
sequence1- first sequence to be comparedsequence2- second sequence to be compared
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SequencesComparator
Simple constructor.Creates a new instance of SequencesComparator with a custom
Equator.It is guaranteed that the comparisons will always be done as
Equator.equate(o1, o2)whereo1belongs to the first sequence ando2belongs to the second sequence.- Parameters:
sequence1- first sequence to be comparedsequence2- second sequence to be comparedequator- the equator to use for testing object equality
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Method Details
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getScript
Gets theEditScriptobject.It is guaranteed that the objects embedded in the
insert commandscome from the second sequence and that the objects embedded in either thedelete commandsorkeep commandscome from the first sequence. This can be important if subclassing is used for some elements in the first sequence and theequalsmethod is specialized.- Returns:
- the edit script resulting from the comparison of the two sequences
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