Package org.assertj.core.util.diff.myers

Class MyersDiff<T>

java.lang.Object

org.assertj.core.util.diff.myers.MyersDiff<T>

Type Parameters:

T - The type of the compared elements in the 'lines'.

All Implemented Interfaces:

DiffAlgorithm<T>

public class MyersDiff<T>
extends Object
implements DiffAlgorithm<T>

Copy from https://code.google.com/p/java-diff-utils/.

A clean-room implementation of Eugene Myers differencing algorithm.

See the paper at http://www.cs.arizona.edu/people/gene/PAPERS/diff.ps

Author:

Juanco Anez

Field Summary

Fields

Modifier and Type	Field	Description
private Equalizer<T>	equalizer	The equalizer.

Constructor Summary

Constructors

Constructor	Description
MyersDiff()	Constructs an instance of the Myers differencing algorithm.

Method Summary

Modifier and Type	Method	Description
PathNode	buildPath(List<T> orig, List<T> rev)	Computes the minimum diffpath that expresses de differences between the original and revised sequences, according to Gene Myers differencing algorithm.
Patch<T>	buildRevision(PathNode path, List<T> orig, List<T> rev)	Constructs a Patch from a difference path.
private List<T>	copyOfRange(List<T> original, int fromIndex, int to)	Creates a new list containing the elements returned by List.subList(int, int).
Patch<T>	diff(List<T> original, List<T> revised)	Computes the difference between the original sequence and the revised sequence and returns it as a Patch object.
private boolean	equals(T orig, T rev)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

equalizer

private final Equalizer<T> equalizer

The equalizer.

Constructor Detail

MyersDiff

public MyersDiff()

Constructs an instance of the Myers differencing algorithm.

Method Detail

diff

public Patch<T> diff(List<T> original,
                     List<T> revised)

Computes the difference between the original sequence and the revised sequence and returns it as a Patch object. Return empty diff if get the error while procession the difference.

Specified by:

diff in interface DiffAlgorithm<T>

Parameters:

original - The original sequence. Must not be null.

revised - The revised sequence. Must not be null.

Returns:

The patch representing the diff of the given sequences. Never null.

buildPath

public PathNode buildPath(List<T> orig,
                          List<T> rev)

Computes the minimum diffpath that expresses de differences between the original and revised sequences, according to Gene Myers differencing algorithm.

Parameters:

orig - The original sequence.

rev - The revised sequence.

Returns:

A minimum Path across the differences graph.

Throws:

IllegalStateException - if a diff path could not be found.

equals

private boolean equals(T orig,
                       T rev)

buildRevision

public Patch<T> buildRevision(PathNode path,
                              List<T> orig,
                              List<T> rev)

Constructs a Patch from a difference path.

Parameters:

path - The path.

orig - The original sequence.

rev - The revised sequence.

Returns:

A Patch script corresponding to the path.

copyOfRange

private List<T> copyOfRange(List<T> original,
                            int fromIndex,
                            int to)

Creates a new list containing the elements returned by List.subList(int, int).

Parameters:

original - The original sequence. Must not be null.

fromIndex - low endpoint (inclusive) of the subList.

to - high endpoint (exclusive) of the subList.

Returns:

A new list of the specified range within the original list.