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diff --git a/.files/Diff.java b/.files/Diff.java deleted file mode 100644 index 71e220b..0000000 --- a/.files/Diff.java +++ /dev/null @@ -1,896 +0,0 @@ -/* - * $Log: Diff.java,v $ - * Revision 1.7 2009/01/19 03:05:26 stuart - * Fix StackOverflow bug with heuristic on reported by Jimmy Han. - * - * Revision 1.6 2003/03/06 22:51:32 stuart - * Convert to CVS - * - * Revision 1.5 2002/07/19 19:14:40 stuart - * fix reverseScript, make change ctor public, update docs - * - * Revision 1.4 2002/04/09 17:53:39 stuart - * More flexible interface for diff() function. - * - * Revision 1.3 2000/03/03 21:58:03 stuart - * move discard_confusing_lines and shift_boundaries to class file_data - * - * Revision 1.2 2000/03/02 16:37:38 stuart - * Add GPL and copyright - * - */ -package bmsi.util; - -import java.util.Hashtable; - -/** A class to compare vectors of objects. The result of comparison - is a list of <code>change</code> objects which form an - edit script. The objects compared are traditionally lines - of text from two files. Comparison options such as "ignore - whitespace" are implemented by modifying the <code>equals</code> - and <code>hashcode</code> methods for the objects compared. -<p> - The basic algorithm is described in: </br> - "An O(ND) Difference Algorithm and its Variations", Eugene Myers, - Algorithmica Vol. 1 No. 2, 1986, p 251. -<p> - This class outputs different results from GNU diff 1.15 on some - inputs. Our results are actually better (smaller change list, smaller - total size of changes), but it would be nice to know why. Perhaps - there is a memory overwrite bug in GNU diff 1.15. - - @author Stuart D. Gathman, translated from GNU diff 1.15 - Copyright (C) 2000 Business Management Systems, Inc. -<p> - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 1, or (at your option) - any later version. -<p> - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. -<p> - You should have received a copy of the <a href=COPYING.txt> - GNU General Public License</a> - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - - */ - -public class Diff { - - /** Prepare to find differences between two arrays. Each element of - the arrays is translated to an "equivalence number" based on - the result of <code>equals</code>. The original Object arrays - are no longer needed for computing the differences. They will - be needed again later to print the results of the comparison as - an edit script, if desired. - */ - public Diff(Object[] a,Object[] b) { - Hashtable h = new Hashtable(a.length + b.length); - filevec[0] = new file_data(a,h); - filevec[1] = new file_data(b,h); - } - - /** 1 more than the maximum equivalence value used for this or its - sibling file. */ - private int equiv_max = 1; - - /** When set to true, the comparison uses a heuristic to speed it up. - With this heuristic, for files with a constant small density - of changes, the algorithm is linear in the file size. */ - public boolean heuristic = false; - - /** When set to true, the algorithm returns a guarranteed minimal - set of changes. This makes things slower, sometimes much slower. */ - public boolean no_discards = false; - - private int[] xvec, yvec; /* Vectors being compared. */ - private int[] fdiag; /* Vector, indexed by diagonal, containing - the X coordinate of the point furthest - along the given diagonal in the forward - search of the edit matrix. */ - private int[] bdiag; /* Vector, indexed by diagonal, containing - the X coordinate of the point furthest - along the given diagonal in the backward - search of the edit matrix. */ - private int fdiagoff, bdiagoff; - private final file_data[] filevec = new file_data[2]; - private int cost; - /** Snakes bigger than this are considered "big". */ - private static final int SNAKE_LIMIT = 20; - - /** Find the midpoint of the shortest edit script for a specified - portion of the two files. - - We scan from the beginnings of the files, and simultaneously from the ends, - doing a breadth-first search through the space of edit-sequence. - When the two searches meet, we have found the midpoint of the shortest - edit sequence. - - The value returned is the number of the diagonal on which the midpoint lies. - The diagonal number equals the number of inserted lines minus the number - of deleted lines (counting only lines before the midpoint). - The edit cost is stored into COST; this is the total number of - lines inserted or deleted (counting only lines before the midpoint). - - This function assumes that the first lines of the specified portions - of the two files do not match, and likewise that the last lines do not - match. The caller must trim matching lines from the beginning and end - of the portions it is going to specify. - - Note that if we return the "wrong" diagonal value, or if - the value of bdiag at that diagonal is "wrong", - the worst this can do is cause suboptimal diff output. - It cannot cause incorrect diff output. */ - - private int diag (int xoff, int xlim, int yoff, int ylim) { - final int[] fd = fdiag; // Give the compiler a chance. - final int[] bd = bdiag; // Additional help for the compiler. - final int[] xv = xvec; // Still more help for the compiler. - final int[] yv = yvec; // And more and more . . . - final int dmin = xoff - ylim; // Minimum valid diagonal. - final int dmax = xlim - yoff; // Maximum valid diagonal. - final int fmid = xoff - yoff; // Center diagonal of top-down search. - final int bmid = xlim - ylim; // Center diagonal of bottom-up search. - int fmin = fmid, fmax = fmid; // Limits of top-down search. - int bmin = bmid, bmax = bmid; // Limits of bottom-up search. - /* True if southeast corner is on an odd - diagonal with respect to the northwest. */ - final boolean odd = (fmid - bmid & 1) != 0; - - fd[fdiagoff + fmid] = xoff; - bd[bdiagoff + bmid] = xlim; - - for (int c = 1;; ++c) - { - int d; /* Active diagonal. */ - boolean big_snake = false; - - /* Extend the top-down search by an edit step in each diagonal. */ - if (fmin > dmin) - fd[fdiagoff + --fmin - 1] = -1; - else - ++fmin; - if (fmax < dmax) - fd[fdiagoff + ++fmax + 1] = -1; - else - --fmax; - for (d = fmax; d >= fmin; d -= 2) - { - int x, y, oldx, tlo = fd[fdiagoff + d - 1], thi = fd[fdiagoff + d + 1]; - - if (tlo >= thi) - x = tlo + 1; - else - x = thi; - oldx = x; - y = x - d; - while (x < xlim && y < ylim && xv[x] == yv[y]) { - ++x; ++y; - } - if (x - oldx > SNAKE_LIMIT) - big_snake = true; - fd[fdiagoff + d] = x; - if (odd && bmin <= d && d <= bmax && bd[bdiagoff + d] <= fd[fdiagoff + d]) - { - cost = 2 * c - 1; - return d; - } - } - - /* Similar extend the bottom-up search. */ - if (bmin > dmin) - bd[bdiagoff + --bmin - 1] = Integer.MAX_VALUE; - else - ++bmin; - if (bmax < dmax) - bd[bdiagoff + ++bmax + 1] = Integer.MAX_VALUE; - else - --bmax; - for (d = bmax; d >= bmin; d -= 2) - { - int x, y, oldx, tlo = bd[bdiagoff + d - 1], thi = bd[bdiagoff + d + 1]; - - if (tlo < thi) - x = tlo; - else - x = thi - 1; - oldx = x; - y = x - d; - while (x > xoff && y > yoff && xv[x - 1] == yv[y - 1]) { - --x; --y; - } - if (oldx - x > SNAKE_LIMIT) - big_snake = true; - bd[bdiagoff + d] = x; - if (!odd && fmin <= d && d <= fmax && bd[bdiagoff + d] <= fd[fdiagoff + d]) - { - cost = 2 * c; - return d; - } - } - - /* Heuristic: check occasionally for a diagonal that has made - lots of progress compared with the edit distance. - If we have any such, find the one that has made the most - progress and return it as if it had succeeded. - - With this heuristic, for files with a constant small density - of changes, the algorithm is linear in the file size. */ - - if (c > 200 && big_snake && heuristic) - { - int best = 0; - int bestpos = -1; - - for (d = fmax; d >= fmin; d -= 2) - { - int dd = d - fmid; - int x = fd[fdiagoff + d]; - int y = x - d; - int v = (x - xoff) * 2 - dd; - if (v > 12 * (c + (dd < 0 ? -dd : dd))) - { - if (v > best - && xoff + SNAKE_LIMIT <= x && x < xlim - && yoff + SNAKE_LIMIT <= y && y < ylim) - { - /* We have a good enough best diagonal; - now insist that it end with a significant snake. */ - int k; - - for (k = 1; xvec[x - k] == yvec[y - k]; k++) - if (k == SNAKE_LIMIT) - { - best = v; - bestpos = d; - break; - } - } - } - } - if (best > 0) - { - cost = 2 * c - 1; - return bestpos; - } - - best = 0; - for (d = bmax; d >= bmin; d -= 2) - { - int dd = d - bmid; - int x = bd[bdiagoff + d]; - int y = x - d; - int v = (xlim - x) * 2 + dd; - if (v > 12 * (c + (dd < 0 ? -dd : dd))) - { - if (v > best - && xoff < x && x <= xlim - SNAKE_LIMIT - && yoff < y && y <= ylim - SNAKE_LIMIT) - { - /* We have a good enough best diagonal; - now insist that it end with a significant snake. */ - int k; - - for (k = 0; xvec[x + k] == yvec[y + k]; k++) - if (k == SNAKE_LIMIT) - { - best = v; - bestpos = d; - break; - } - } - } - } - if (best > 0) - { - cost = 2 * c - 1; - return bestpos; - } - } - } - } - - /** Compare in detail contiguous subsequences of the two files - which are known, as a whole, to match each other. - - The results are recorded in the vectors filevec[N].changed_flag, by - storing a 1 in the element for each line that is an insertion or deletion. - - The subsequence of file 0 is [XOFF, XLIM) and likewise for file 1. - - Note that XLIM, YLIM are exclusive bounds. - All line numbers are origin-0 and discarded lines are not counted. */ - - private void compareseq (int xoff, int xlim, int yoff, int ylim) { - /* Slide down the bottom initial diagonal. */ - while (xoff < xlim && yoff < ylim && xvec[xoff] == yvec[yoff]) { - ++xoff; ++yoff; - } - /* Slide up the top initial diagonal. */ - while (xlim > xoff && ylim > yoff && xvec[xlim - 1] == yvec[ylim - 1]) { - --xlim; --ylim; - } - - /* Handle simple cases. */ - if (xoff == xlim) - while (yoff < ylim) - filevec[1].changed_flag[1+filevec[1].realindexes[yoff++]] = true; - else if (yoff == ylim) - while (xoff < xlim) - filevec[0].changed_flag[1+filevec[0].realindexes[xoff++]] = true; - else - { - /* Find a point of correspondence in the middle of the files. */ - - int d = diag (xoff, xlim, yoff, ylim); - int c = cost; - int f = fdiag[fdiagoff + d]; - int b = bdiag[bdiagoff + d]; - - if (c == 1) - { - /* This should be impossible, because it implies that - one of the two subsequences is empty, - and that case was handled above without calling `diag'. - Let's verify that this is true. */ - throw new IllegalArgumentException("Empty subsequence"); - } - else - { - /* Use that point to split this problem into two subproblems. */ - compareseq (xoff, b, yoff, b - d); - /* This used to use f instead of b, - but that is incorrect! - It is not necessarily the case that diagonal d - has a snake from b to f. */ - compareseq (b, xlim, b - d, ylim); - } - } - } - - /** Discard lines from one file that have no matches in the other file. - */ - - private void discard_confusing_lines() { - filevec[0].discard_confusing_lines(filevec[1]); - filevec[1].discard_confusing_lines(filevec[0]); - } - - private boolean inhibit = false; - - /** Adjust inserts/deletes of blank lines to join changes - as much as possible. - */ - - private void shift_boundaries() { - if (inhibit) - return; - filevec[0].shift_boundaries(filevec[1]); - filevec[1].shift_boundaries(filevec[0]); - } - - public interface ScriptBuilder { - /** Scan the tables of which lines are inserted and deleted, - producing an edit script. - @param changed0 true for lines in first file which do not match 2nd - @param len0 number of lines in first file - @param changed1 true for lines in 2nd file which do not match 1st - @param len1 number of lines in 2nd file - @return a linked list of changes - or null - */ - public change build_script( - boolean[] changed0,int len0, - boolean[] changed1,int len1 - ); - } - - /** Scan the tables of which lines are inserted and deleted, - producing an edit script in reverse order. */ - - static class ReverseScript implements ScriptBuilder { - public change build_script( - final boolean[] changed0,int len0, - final boolean[] changed1,int len1) - { - change script = null; - int i0 = 0, i1 = 0; - while (i0 < len0 || i1 < len1) { - if (changed0[1+i0] || changed1[1+i1]) { - int line0 = i0, line1 = i1; - - /* Find # lines changed here in each file. */ - while (changed0[1+i0]) ++i0; - while (changed1[1+i1]) ++i1; - - /* Record this change. */ - script = new change(line0, line1, i0 - line0, i1 - line1, script); - } - - /* We have reached lines in the two files that match each other. */ - i0++; i1++; - } - - return script; - } - } - - static class ForwardScript implements ScriptBuilder { - /** Scan the tables of which lines are inserted and deleted, - producing an edit script in forward order. */ - public change build_script( - final boolean[] changed0,int len0, - final boolean[] changed1,int len1) - { - change script = null; - int i0 = len0, i1 = len1; - - while (i0 >= 0 || i1 >= 0) - { - if (changed0[i0] || changed1[i1]) - { - int line0 = i0, line1 = i1; - - /* Find # lines changed here in each file. */ - while (changed0[i0]) --i0; - while (changed1[i1]) --i1; - - /* Record this change. */ - script = new change(i0, i1, line0 - i0, line1 - i1, script); - } - - /* We have reached lines in the two files that match each other. */ - i0--; i1--; - } - - return script; - } - } - - /** Standard ScriptBuilders. */ - public final static ScriptBuilder - forwardScript = new ForwardScript(), - reverseScript = new ReverseScript(); - - /* Report the differences of two files. DEPTH is the current directory - depth. */ - public final change diff_2(final boolean reverse) { - return diff(reverse ? reverseScript : forwardScript); - } - - /** Get the results of comparison as an edit script. The script - is described by a list of changes. The standard ScriptBuilder - implementations provide for forward and reverse edit scripts. - Alternate implementations could, for instance, list common elements - instead of differences. - @param bld an object to build the script from change flags - @return the head of a list of changes - */ - public change diff(final ScriptBuilder bld) { - - /* Some lines are obviously insertions or deletions - because they don't match anything. Detect them now, - and avoid even thinking about them in the main comparison algorithm. */ - - discard_confusing_lines (); - - /* Now do the main comparison algorithm, considering just the - undiscarded lines. */ - - xvec = filevec[0].undiscarded; - yvec = filevec[1].undiscarded; - - int diags = - filevec[0].nondiscarded_lines + filevec[1].nondiscarded_lines + 3; - fdiag = new int[diags]; - fdiagoff = filevec[1].nondiscarded_lines + 1; - bdiag = new int[diags]; - bdiagoff = filevec[1].nondiscarded_lines + 1; - - compareseq (0, filevec[0].nondiscarded_lines, - 0, filevec[1].nondiscarded_lines); - fdiag = null; - bdiag = null; - - /* Modify the results slightly to make them prettier - in cases where that can validly be done. */ - - shift_boundaries (); - - /* Get the results of comparison in the form of a chain - of `struct change's -- an edit script. */ - return bld.build_script( - filevec[0].changed_flag, - filevec[0].buffered_lines, - filevec[1].changed_flag, - filevec[1].buffered_lines - ); - - } - - /** The result of comparison is an "edit script": a chain of change objects. - Each change represents one place where some lines are deleted - and some are inserted. - - LINE0 and LINE1 are the first affected lines in the two files (origin 0). - DELETED is the number of lines deleted here from file 0. - INSERTED is the number of lines inserted here in file 1. - - If DELETED is 0 then LINE0 is the number of the line before - which the insertion was done; vice versa for INSERTED and LINE1. */ - - public static class change { - /** Previous or next edit command. */ - public change link; - /** # lines of file 1 changed here. */ - public final int inserted; - /** # lines of file 0 changed here. */ - public final int deleted; - /** Line number of 1st deleted line. */ - public final int line0; - /** Line number of 1st inserted line. */ - public final int line1; - - /** Cons an additional entry onto the front of an edit script OLD. - LINE0 and LINE1 are the first affected lines in the two files (origin 0). - DELETED is the number of lines deleted here from file 0. - INSERTED is the number of lines inserted here in file 1. - - If DELETED is 0 then LINE0 is the number of the line before - which the insertion was done; vice versa for INSERTED and LINE1. */ - public change(int line0, int line1, int deleted, int inserted, change old) { - this.line0 = line0; - this.line1 = line1; - this.inserted = inserted; - this.deleted = deleted; - this.link = old; - //System.err.println(line0+","+line1+","+inserted+","+deleted); - } - } - - /** Data on one input file being compared. - */ - - class file_data { - - /** Allocate changed array for the results of comparison. */ - void clear() { - /* Allocate a flag for each line of each file, saying whether that line - is an insertion or deletion. - Allocate an extra element, always zero, at each end of each vector. - */ - changed_flag = new boolean[buffered_lines + 2]; - } - - /** Return equiv_count[I] as the number of lines in this file - that fall in equivalence class I. - @return the array of equivalence class counts. - */ - int[] equivCount() { - int[] equiv_count = new int[equiv_max]; - for (int i = 0; i < buffered_lines; ++i) - ++equiv_count[equivs[i]]; - return equiv_count; - } - - /** Discard lines that have no matches in another file. - - A line which is discarded will not be considered by the actual - comparison algorithm; it will be as if that line were not in the file. - The file's `realindexes' table maps virtual line numbers - (which don't count the discarded lines) into real line numbers; - this is how the actual comparison algorithm produces results - that are comprehensible when the discarded lines are counted. -<p> - When we discard a line, we also mark it as a deletion or insertion - so that it will be printed in the output. - @param f the other file - */ - void discard_confusing_lines(file_data f) { - clear(); - /* Set up table of which lines are going to be discarded. */ - final byte[] discarded = discardable(f.equivCount()); - - /* Don't really discard the provisional lines except when they occur - in a run of discardables, with nonprovisionals at the beginning - and end. */ - filterDiscards(discarded); - - /* Actually discard the lines. */ - discard(discarded); - } - - /** Mark to be discarded each line that matches no line of another file. - If a line matches many lines, mark it as provisionally discardable. - @see equivCount() - @param counts The count of each equivalence number for the other file. - @return 0=nondiscardable, 1=discardable or 2=provisionally discardable - for each line - */ - - private byte[] discardable(final int[] counts) { - final int end = buffered_lines; - final byte[] discards = new byte[end]; - final int[] equivs = this.equivs; - int many = 5; - int tem = end / 64; - - /* Multiply MANY by approximate square root of number of lines. - That is the threshold for provisionally discardable lines. */ - while ((tem = tem >> 2) > 0) - many *= 2; - - for (int i = 0; i < end; i++) - { - int nmatch; - if (equivs[i] == 0) - continue; - nmatch = counts[equivs[i]]; - if (nmatch == 0) - discards[i] = 1; - else if (nmatch > many) - discards[i] = 2; - } - return discards; - } - - /** Don't really discard the provisional lines except when they occur - in a run of discardables, with nonprovisionals at the beginning - and end. */ - - private void filterDiscards(final byte[] discards) { - final int end = buffered_lines; - - for (int i = 0; i < end; i++) - { - /* Cancel provisional discards not in middle of run of discards. */ - if (discards[i] == 2) - discards[i] = 0; - else if (discards[i] != 0) - { - /* We have found a nonprovisional discard. */ - int j; - int length; - int provisional = 0; - - /* Find end of this run of discardable lines. - Count how many are provisionally discardable. */ - for (j = i; j < end; j++) - { - if (discards[j] == 0) - break; - if (discards[j] == 2) - ++provisional; - } - - /* Cancel provisional discards at end, and shrink the run. */ - while (j > i && discards[j - 1] == 2) { - discards[--j] = 0; --provisional; - } - - /* Now we have the length of a run of discardable lines - whose first and last are not provisional. */ - length = j - i; - - /* If 1/4 of the lines in the run are provisional, - cancel discarding of all provisional lines in the run. */ - if (provisional * 4 > length) - { - while (j > i) - if (discards[--j] == 2) - discards[j] = 0; - } - else - { - int consec; - int minimum = 1; - int tem = length / 4; - - /* MINIMUM is approximate square root of LENGTH/4. - A subrun of two or more provisionals can stand - when LENGTH is at least 16. - A subrun of 4 or more can stand when LENGTH >= 64. */ - while ((tem = tem >> 2) > 0) - minimum *= 2; - minimum++; - - /* Cancel any subrun of MINIMUM or more provisionals - within the larger run. */ - for (j = 0, consec = 0; j < length; j++) - if (discards[i + j] != 2) - consec = 0; - else if (minimum == ++consec) - /* Back up to start of subrun, to cancel it all. */ - j -= consec; - else if (minimum < consec) - discards[i + j] = 0; - - /* Scan from beginning of run - until we find 3 or more nonprovisionals in a row - or until the first nonprovisional at least 8 lines in. - Until that point, cancel any provisionals. */ - for (j = 0, consec = 0; j < length; j++) - { - if (j >= 8 && discards[i + j] == 1) - break; - if (discards[i + j] == 2) { - consec = 0; discards[i + j] = 0; - } - else if (discards[i + j] == 0) - consec = 0; - else - consec++; - if (consec == 3) - break; - } - - /* I advances to the last line of the run. */ - i += length - 1; - - /* Same thing, from end. */ - for (j = 0, consec = 0; j < length; j++) - { - if (j >= 8 && discards[i - j] == 1) - break; - if (discards[i - j] == 2) { - consec = 0; discards[i - j] = 0; - } - else if (discards[i - j] == 0) - consec = 0; - else - consec++; - if (consec == 3) - break; - } - } - } - } - } - - /** Actually discard the lines. - @param discards flags lines to be discarded - */ - private void discard(final byte[] discards) { - final int end = buffered_lines; - int j = 0; - for (int i = 0; i < end; ++i) - if (no_discards || discards[i] == 0) - { - undiscarded[j] = equivs[i]; - realindexes[j++] = i; - } - else - changed_flag[1+i] = true; - nondiscarded_lines = j; - } - - file_data(Object[] data,Hashtable h) { - buffered_lines = data.length; - - equivs = new int[buffered_lines]; - undiscarded = new int[buffered_lines]; - realindexes = new int[buffered_lines]; - - for (int i = 0; i < data.length; ++i) { - Integer ir = (Integer)h.get(data[i]); - if (ir == null) - h.put(data[i],new Integer(equivs[i] = equiv_max++)); - else - equivs[i] = ir.intValue(); - } - } - - /** Adjust inserts/deletes of blank lines to join changes - as much as possible. - - We do something when a run of changed lines include a blank - line at one end and have an excluded blank line at the other. - We are free to choose which blank line is included. - `compareseq' always chooses the one at the beginning, - but usually it is cleaner to consider the following blank line - to be the "change". The only exception is if the preceding blank line - would join this change to other changes. - @param f the file being compared against - */ - - void shift_boundaries(file_data f) { - final boolean[] changed = changed_flag; - final boolean[] other_changed = f.changed_flag; - int i = 0; - int j = 0; - int i_end = buffered_lines; - int preceding = -1; - int other_preceding = -1; - - for (;;) - { - int start, end, other_start; - - /* Scan forwards to find beginning of another run of changes. - Also keep track of the corresponding point in the other file. */ - - while (i < i_end && !changed[1+i]) - { - while (other_changed[1+j++]) - /* Non-corresponding lines in the other file - will count as the preceding batch of changes. */ - other_preceding = j; - i++; - } - - if (i == i_end) - break; - - start = i; - other_start = j; - - for (;;) - { - /* Now find the end of this run of changes. */ - - while (i < i_end && changed[1+i]) i++; - end = i; - - /* If the first changed line matches the following unchanged one, - and this run does not follow right after a previous run, - and there are no lines deleted from the other file here, - then classify the first changed line as unchanged - and the following line as changed in its place. */ - - /* You might ask, how could this run follow right after another? - Only because the previous run was shifted here. */ - - if (end != i_end - && equivs[start] == equivs[end] - && !other_changed[1+j] - && end != i_end - && !((preceding >= 0 && start == preceding) - || (other_preceding >= 0 - && other_start == other_preceding))) - { - changed[1+end++] = true; - changed[1+start++] = false; - ++i; - /* Since one line-that-matches is now before this run - instead of after, we must advance in the other file - to keep in synch. */ - ++j; - } - else - break; - } - - preceding = i; - other_preceding = j; - } - } - - /** Number of elements (lines) in this file. */ - final int buffered_lines; - - /** Vector, indexed by line number, containing an equivalence code for - each line. It is this vector that is actually compared with that - of another file to generate differences. */ - private final int[] equivs; - - /** Vector, like the previous one except that - the elements for discarded lines have been squeezed out. */ - final int[] undiscarded; - - /** Vector mapping virtual line numbers (not counting discarded lines) - to real ones (counting those lines). Both are origin-0. */ - final int[] realindexes; - - /** Total number of nondiscarded lines. */ - int nondiscarded_lines; - - /** Array, indexed by real origin-1 line number, - containing true for a line that is an insertion or a deletion. - The results of comparison are stored here. */ - boolean[] changed_flag; - - } -} |