Improve matching of multi-line comments with differences in empty lines

JabRef/jabref-koppor#716
org.jabref.gui.openoffice.OOBibBase
(#976)

Author: tsantalis

src/main/java/gr/uom/java/xmi/UMLComment.java

@@ -102,6 +102,12 @@ public String toString() {
 		return sb.toString();
 	}
 
+	public boolean equalTextIgnoringEmptyLines(UMLComment other) {
+		String text1 = this.getText().replaceAll("(?m)^\\s+$", "").replaceAll("(?m)^\\n", "").replaceAll("(\\r?\\n)$", "");
+		String text2 = other.getText().replaceAll("(?m)^\\s+$", "").replaceAll("(?m)^\\n", "").replaceAll("(\\r?\\n)$", "");
+		return text1.equals(text2) || text1.equals(text2 + "*") || text2.equals(text1 + "*");
+	}
+
 	public boolean isCommentedCode() {
 		if(locationInfo.getCodeElementType().equals(CodeElementType.LINE_COMMENT)) {
 			String text = getText();

src/main/java/gr/uom/java/xmi/diff/UMLCommentListDiff.java

@@ -449,6 +449,9 @@ public static List<Integer> findAllMatchingIndices(List<UMLComment> fragments, U
 			if(comment.getText().equals(element.getText())) {
 				matchingIndices.add(i);
 			}
+			else if(comment.equalTextIgnoringEmptyLines(element)) {
+				matchingIndices.add(i);
+			}
 		}
 		return matchingIndices;
 	}