difflib.DiffRowGenerator Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of diffutils Show documentation
Show all versions of diffutils Show documentation
The DiffUtils library for computing diffs, applying patches, generationg side-by-side view in Java
/*
Copyright 2009 Dmitry Naumenko ([email protected])
This file is part of Java Diff Utills Library.
Java Diff Utills Library 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 3 of the License, or
(at your option) any later version.
Java Diff Utills Library 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.
You should have received a copy of the GNU General Public License
along with Java Diff Utills Library. If not, see
* DiffRowGenerator generator = new DiffRowGenerator.Builder().showInlineDiffs(true).
* ignoreWhiteSpaces(true).columnWidth(100).build();
*
*
* @author Dmitry Naumenko
*/
public class DiffRowGenerator {
private final boolean showInlineDiffs;
private final boolean ignoreWhiteSpaces;
private final boolean ignoreBlankLines;
private final String InlineOldTag;
private final String InlineNewTag;
private final String InlineOldCssClass;
private final String InlineNewCssClass;
private final int columnWidth;
/**
* This class used for building the DiffRowGenerator.
* @author dmitry
*
*/
public static class Builder {
private boolean showInlineDiffs = false;
private boolean ignoreWhiteSpaces = true;
private boolean ignoreBlankLines = true;
private String InlineOldTag = "span";
private String InlineNewTag = "span";
private String InlineOldCssClass = "editOldInline";
private String InlineNewCssClass = "editNewInline";
private int columnWidth = 80;
/**
* Show inline diffs in generating diff rows or not.
* @param val the value to set. Default: false.
* @return builder with configured showInlineDiff parameter
*/
public Builder showInlineDiffs(boolean val) {
showInlineDiffs = val;
return this;
}
/**
* Ignore white spaces in generating diff rows or not.
* @param val the value to set. Default: true.
* @return builder with configured ignoreWhiteSpaces parameter
*/
public Builder ignoreWhiteSpaces(boolean val) {
ignoreWhiteSpaces = val;
return this;
}
/**
* Ignore blank lines in generating diff rows or not.
* @param val the value to set. Default: true.
* @return builder with configured ignoreBlankLines parameter
*/
public Builder ignoreBlankLines(boolean val) {
ignoreBlankLines = val;
return this;
}
/**
* Set the tag used for displaying changes in the original text.
* @param tag the tag to set. Without angle brackets. Default: span.
* @return builder with configured ignoreBlankLines parameter
*/
public Builder InlineOldTag(String tag) {
InlineOldTag = tag;
return this;
}
/**
* Set the tag used for displaying changes in the revised text.
* @param tag the tag to set. Without angle brackets. Default: span.
* @return builder with configured ignoreBlankLines parameter
*/
public Builder InlineNewTag(String tag) {
InlineNewTag = tag;
return this;
}
/**
* Set the css class used for displaying changes in the original text.
* @param cssClass the tag to set. Without any quotes, just word. Default: editOldInline.
* @return builder with configured ignoreBlankLines parameter
*/
public Builder InlineOldCssClass(String cssClass) {
InlineOldCssClass = cssClass;
return this;
}
/**
* Set the css class used for displaying changes in the revised text.
* @param cssClass the tag to set. Without any quotes, just word. Default: editNewInline.
* @return builder with configured ignoreBlankLines parameter
*/
public Builder InlineNewCssClass(String cssClass) {
InlineNewCssClass = cssClass;
return this;
}
/**
* Set the column with of generated lines of original and revised texts.
* @param width the width to set. Making it < 0 doesn't have any sense. Default 80.
* @return builder with configured ignoreBlankLines parameter
*/
public Builder columnWidth(int width) {
if (width > 0) {
columnWidth = width;
}
return this;
}
/**
* Build the DiffRowGenerator. If some parameters is not set, the default values are used.
* @return the customized DiffRowGenerator
*/
public DiffRowGenerator build() {
return new DiffRowGenerator(this);
}
}
private DiffRowGenerator(Builder builder) {
showInlineDiffs = builder.showInlineDiffs;
ignoreWhiteSpaces = builder.ignoreWhiteSpaces; //
ignoreBlankLines = builder.ignoreBlankLines; //
InlineOldTag = builder.InlineOldTag;
InlineNewTag = builder.InlineNewTag;
InlineOldCssClass = builder.InlineOldCssClass;
InlineNewCssClass = builder.InlineNewCssClass;
columnWidth = builder.columnWidth; //
}
/**
* Get the DiffRows describing the difference between original and revised texts using the
* given patch. Useful for displaying side-by-side diff.
*
* @param original the original text
* @param revised the revised text
* @return the DiffRows between original and revised texts
*/
public List generateDiffRows(List original, List revised) {
return generateDiffRows(original, revised, DiffUtils.diff(original, revised));
}
/**
* Generates the DiffRows describing the difference between original and revised texts using the
* given patch. Useful for displaying side-by-side diff.
*
* @param original the original text
* @param revised the revised text
* @param patch the given patch
* @return the DiffRows between original and revised texts
*/
@SuppressWarnings("unchecked")
public List generateDiffRows(List original, List revised, Patch patch) {
// normalize the lines (expand tabs, escape html entities)
original = StringUtills.normalize((List) original);
revised = StringUtills.normalize((List) revised);
// wrap to the column width
original = StringUtills.wrapText((List) original, this.columnWidth);
revised = StringUtills.wrapText((List) revised, this.columnWidth);
List diffRows = new ArrayList();
int endPos = 0;
for (int i = 0; i < patch.getDeltas().size(); i++) {
Delta delta = patch.getDelta(i);
Chunk orig = delta.getOriginal();
Chunk rev = delta.getRevised();
// We should normalize and wrap lines in deltas too.
orig.setLines(StringUtills.normalize((List) orig.getLines()));
rev.setLines(StringUtills.normalize((List) rev.getLines()));
orig.setLines(StringUtills.wrapText((List) orig.getLines(), this.columnWidth));
rev.setLines(StringUtills.wrapText((List) rev.getLines(), this.columnWidth));
// catch the equal prefix for each chunk
for (String line : original.subList(endPos, orig.getPosition())) {
diffRows.add(new DiffRow(Tag.EQUAL, line, line));
}
// Inserted DiffRow
if (delta.getClass().equals(InsertDelta.class)) {
endPos = orig.last() + 1;
for (String line : (List) rev.getLines()) {
diffRows.add(new DiffRow(Tag.INSERT, "", line));
}
continue;
}
// Deleted DiffRow
if (delta.getClass().equals(DeleteDelta.class)) {
endPos = orig.last() + 1;
for (String line : (List) orig.getLines()) {
diffRows.add(new DiffRow(Tag.DELETE, line, ""));
}
continue;
}
if (showInlineDiffs) {
addInlineDiffs(delta);
}
// the changed size is match
if (orig.getSize() == rev.getSize()) {
for (int j = 0; j < orig.getSize(); j++) {
diffRows.add(new DiffRow(Tag.CHANGE, (String) orig.getLines().get(j),
(String) rev.getLines().get(j)));
}
} else if (orig.getSize() > rev.getSize()) {
for (int j = 0; j < orig.getSize(); j++) {
diffRows.add(new DiffRow(Tag.CHANGE, (String) orig.getLines().get(j), rev
.getLines().size() > j ? (String) rev.getLines().get(j) : ""));
}
} else {
for (int j = 0; j < rev.getSize(); j++) {
diffRows.add(new DiffRow(Tag.CHANGE, orig.getLines().size() > j ? (String) orig
.getLines().get(j) : "", (String) rev.getLines().get(j)));
}
}
endPos = orig.last() + 1;
}
// Copy the final matching chunk if any.
for (String line : original.subList(endPos, original.size())) {
diffRows.add(new DiffRow(Tag.EQUAL, line, line));
}
return diffRows;
}
/**
* Add the inline diffs for given delta
* @param delta the given delta
*/
@SuppressWarnings("unchecked")
private void addInlineDiffs(Delta delta) {
List orig = (List) delta.getOriginal().getLines();
List rev = (List) delta.getRevised().getLines();
LinkedList origList = new LinkedList();
for (Character character : join(orig, "\n").toCharArray()) {
origList.add(character.toString());
}
LinkedList revList = new LinkedList();
for (Character character : join(rev, "\n").toCharArray()) {
revList.add(character.toString());
}
List inlineDeltas = DiffUtils.diff(origList, revList).getDeltas();
if (inlineDeltas.size() < 3) {
Collections.reverse(inlineDeltas);
for (Delta inlineDelta : inlineDeltas) {
Chunk inlineOrig = inlineDelta.getOriginal();
Chunk inlineRev = inlineDelta.getRevised();
if (inlineDelta.getClass().equals(DeleteDelta.class)) {
origList = wrapInTag(origList, inlineOrig.getPosition(), inlineOrig
.getPosition()
+ inlineOrig.getSize() + 1, this.InlineOldTag, this.InlineOldCssClass);
} else if (inlineDelta.getClass().equals(InsertDelta.class)) {
revList = wrapInTag(revList, inlineRev.getPosition(), inlineRev.getPosition()
+ inlineRev.getSize() + 1, this.InlineNewTag, this.InlineNewCssClass);
} else if (inlineDelta.getClass().equals(ChangeDelta.class)) {
origList = wrapInTag(origList, inlineOrig.getPosition(), inlineOrig
.getPosition()
+ inlineOrig.getSize() + 1, this.InlineOldTag, this.InlineOldCssClass);
revList = wrapInTag(revList, inlineRev.getPosition(), inlineRev.getPosition()
+ inlineRev.getSize() + 1, this.InlineNewTag, this.InlineNewCssClass);
}
}
StringBuilder origResult = new StringBuilder(), revResult = new StringBuilder();
for (String character : origList) {
origResult.append(character);
}
for (String character : revList) {
revResult.append(character);
}
delta.getOriginal().setLines(Arrays.asList(origResult.toString().split("\n")));
delta.getRevised().setLines(Arrays.asList(revResult.toString().split("\n")));
}
}
/**
* Wrap the elements in the sequence with the given tag
* @param startPosition the position from which tag should start. The counting start from a zero.
* @param endPosition the position before which tag should should be closed.
* @param tag the tag name without angle brackets, just a word
* @param cssClass the optional css class
*/
public static LinkedList wrapInTag(LinkedList sequence, int startPosition,
int endPosition, String tag, String cssClass) {
LinkedList result = (LinkedList) sequence.clone();
StringBuilder tagBuilder = new StringBuilder();
tagBuilder.append("<");
tagBuilder.append(tag);
if (cssClass != null) {
tagBuilder.append(" class=\"");
tagBuilder.append(cssClass);
tagBuilder.append("\"");
}
tagBuilder.append(">");
String startTag = tagBuilder.toString();
tagBuilder.delete(0, tagBuilder.length());
tagBuilder.append("");
String endTag = tagBuilder.toString();
result.add(startPosition, startTag);
result.add(endPosition, endTag);
return result;
}
/**
* Wrap the given line with the given tag
* @param line the given line
* @param tag the tag name without angle brackets, just a word
* @param cssClass the optional css class
* @return the wrapped string
*/
public static String wrapInTag(String line, String tag, String cssClass) {
StringBuilder tagBuilder = new StringBuilder();
tagBuilder.append("<");
tagBuilder.append(tag);
if (cssClass != null) {
tagBuilder.append(" class=\"");
tagBuilder.append(cssClass);
tagBuilder.append("\"");
}
tagBuilder.append(">");
String startTag = tagBuilder.toString();
tagBuilder.delete(0, tagBuilder.length());
tagBuilder.append("");
String endTag = tagBuilder.toString();
return startTag + line + endTag;
}
/**
* The helper method for joining collections
* @param
* @param objs the collection to join
* @param delimiter the delimiter to use
* @return the joined string
*/
private static String join(final Iterable objs, final String delimiter) {
Iterator iter = objs.iterator();
if (!iter.hasNext()) {
return "";
}
StringBuffer buffer = new StringBuffer(String.valueOf(iter.next()));
while (iter.hasNext()) {
buffer.append(delimiter).append(String.valueOf(iter.next()));
}
return buffer.toString();
}
}