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Diffstat (limited to 'org.eclipse.m2e.refactoring/src/org/eclipse/m2e/refactoring/ChangeCreator.java')
-rw-r--r--org.eclipse.m2e.refactoring/src/org/eclipse/m2e/refactoring/ChangeCreator.java187
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diff --git a/org.eclipse.m2e.refactoring/src/org/eclipse/m2e/refactoring/ChangeCreator.java b/org.eclipse.m2e.refactoring/src/org/eclipse/m2e/refactoring/ChangeCreator.java
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+++ b/org.eclipse.m2e.refactoring/src/org/eclipse/m2e/refactoring/ChangeCreator.java
@@ -0,0 +1,187 @@
+/*******************************************************************************
+ * Copyright (c) 2008-2010 Sonatype, Inc.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ * Sonatype, Inc. - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.m2e.refactoring;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+
+import org.eclipse.compare.rangedifferencer.IRangeComparator;
+import org.eclipse.compare.rangedifferencer.RangeDifference;
+import org.eclipse.compare.rangedifferencer.RangeDifferencer;
+import org.eclipse.core.resources.IFile;
+import org.eclipse.jface.text.BadLocationException;
+import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.IRegion;
+import org.eclipse.ltk.core.refactoring.TextFileChange;
+import org.eclipse.m2e.core.core.MavenLogger;
+import org.eclipse.text.edits.DeleteEdit;
+import org.eclipse.text.edits.InsertEdit;
+import org.eclipse.text.edits.MultiTextEdit;
+import org.eclipse.text.edits.ReplaceEdit;
+import org.eclipse.text.edits.TextEdit;
+import org.eclipse.text.edits.TextEditGroup;
+
+
+/**
+ * This class creates an org.eclipse.ltk.core.refactoring.DocumentChange instance based on old and new text values
+ *
+ * @author Anton Kraev
+ */
+public class ChangeCreator {
+ private String label;
+
+ private IDocument oldDocument;
+
+ private IDocument newDocument;
+
+ private IFile oldFile;
+
+ public ChangeCreator(IFile oldFile, IDocument oldDocument, IDocument newDocument, String label) {
+ this.newDocument = newDocument;
+ this.oldDocument = oldDocument;
+ this.oldFile = oldFile;
+ this.label = label;
+ }
+
+ public TextFileChange createChange() throws Exception {
+ TextFileChange change = new TextFileChange(label, oldFile);
+ // change.setSaveMode(TextFileChange.FORCE_SAVE);
+ change.setEdit(new MultiTextEdit());
+ Object leftSide = new LineComparator(oldDocument);
+ Object rightSide = new LineComparator(newDocument);
+
+ RangeDifference[] differences = RangeDifferencer.findDifferences((IRangeComparator) leftSide, (IRangeComparator) rightSide);
+ int insertOffset = 0;
+ for(int i = 0; i < differences.length; i++ ) {
+ RangeDifference curr = differences[i];
+ int startLine = 0;
+ // when comparing 2 files, only RangeDifference.CHANGE is possible, no need to test
+ if (curr.rightLength() == curr.leftLength()) {
+ // replace
+ startLine = curr.rightStart();
+ int endLine = curr.rightEnd() - 1;
+ for(int j = startLine; j <= endLine; j++ ) {
+ int newPos = curr.leftStart() - startLine + j;
+ String newText = newDocument.get(newDocument.getLineOffset(newPos), newDocument.getLineLength(newPos));
+ addEdit(change, startLine, new ReplaceEdit(oldDocument.getLineOffset(j), oldDocument.getLineLength(j), newText));
+ }
+ } else if (curr.rightLength() > 0 && curr.leftLength() == 0) {
+ // insert
+ startLine = curr.rightStart();
+ int endLine = curr.rightEnd() - 1;
+ int posInsert = oldDocument.getLineOffset(curr.leftStart());
+ String newText = ""; //$NON-NLS-1$
+ for(int j = startLine; j <= endLine; j++ ) {
+ int newPos = curr.leftStart() - startLine + j + insertOffset;
+ newText += newDocument.get(newDocument.getLineOffset(newPos), newDocument.getLineLength(newPos));
+ }
+ if(newText.length() > 0){
+ addEdit(change, startLine, new InsertEdit(posInsert, newText));
+ }
+ insertOffset += curr.rightEnd() - curr.rightStart();
+ } else if (curr.leftLength() > 0 && curr.rightLength() == 0) {
+ // delete
+ startLine = curr.leftStart();
+ int endLine = curr.leftEnd() - 1;
+ int startOffset = oldDocument.getLineOffset(startLine);
+ int endOffset = 0;
+ for(int j = startLine; j <= endLine; j++ ) {
+ endOffset += oldDocument.getLineLength(j);
+ }
+ addEdit(change, startLine, new DeleteEdit(startOffset, endOffset));
+ insertOffset -= (curr.leftEnd() - curr.leftStart());
+ } else {
+ // unhandled
+ }
+ }
+ return change;
+ }
+
+ private void addEdit(TextFileChange change, int startLine, TextEdit edit) {
+ change.addTextEditGroup(new TextEditGroup("Line " + (startLine + 1), edit));
+ change.addEdit(edit);
+ }
+
+ public static class LineComparator implements IRangeComparator {
+ private final IDocument document;
+ private final ArrayList<Integer> hashes;
+
+ /**
+ * Create a line comparator for the given document.
+ *
+ * @param document
+ */
+ public LineComparator(IDocument document) {
+ this.document = document;
+ this.hashes = new ArrayList<Integer>(Arrays.asList(new Integer[document.getNumberOfLines()]));
+ }
+
+ /*
+ * @see org.eclipse.compare.rangedifferencer.IRangeComparator#getRangeCount()
+ */
+ public int getRangeCount() {
+ return document.getNumberOfLines();
+ }
+
+ /*
+ * @see org.eclipse.compare.rangedifferencer.IRangeComparator#rangesEqual(int, org.eclipse.compare.rangedifferencer.IRangeComparator, int)
+ */
+ public boolean rangesEqual(int thisIndex, IRangeComparator other, int otherIndex) {
+ try {
+ return getHash(thisIndex).equals(((LineComparator) other).getHash(otherIndex));
+ } catch (BadLocationException e) {
+ MavenLogger.log("Problem comparing", e);
+ return false;
+ }
+ }
+
+ /*
+ * @see org.eclipse.compare.rangedifferencer.IRangeComparator#skipRangeComparison(int, int, org.eclipse.compare.rangedifferencer.IRangeComparator)
+ */
+ public boolean skipRangeComparison(int length, int maxLength, IRangeComparator other) {
+ return false;
+ }
+
+ /**
+ * @param line the number of the line in the document to get the hash for
+ * @return the hash of the line
+ * @throws BadLocationException if the line number is invalid
+ */
+ private Integer getHash(int line) throws BadLocationException {
+ Integer hash = hashes.get(line);
+ if (hash == null) {
+ IRegion lineRegion;
+ lineRegion = document.getLineInformation(line);
+ String lineContents= document.get(lineRegion.getOffset(), lineRegion.getLength());
+ hash = new Integer(computeDJBHash(lineContents));
+ hashes.set(line, hash);
+ }
+ return hash;
+ }
+
+ /**
+ * Compute a hash using the DJB hash algorithm
+ *
+ * @param string the string for which to compute a hash
+ * @return the DJB hash value of the string
+ */
+ private int computeDJBHash(String string) {
+ int hash = 5381;
+ int len = string.length();
+ for (int i = 0; i < len; i++) {
+ hash = (hash << 5) + hash + string.charAt(i);
+ }
+ return hash;
+ }
+ }
+
+}

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