Program: 62441
Project: 62441
Buggy source:
public void generateDocbook(WebEngine webEngine,Path currentPath,boolean showIndicator){
  try {
    Path bookAsc=bookPathResolver.resolve(currentPath);
    if (Objects.isNull(bookAsc)) {
      IOHelper.writeToFile(currentPath.resolve("String_Node_Str"),"String_Node_Str",CREATE,TRUNCATE_EXISTING);
      return;
    }
    if (showIndicator)     indikatorService.startCycle();
    List<String> bookAscLines=Files.readAllLines(bookAsc);
    StringBuffer allAscChapters=new StringBuffer();
    for (int i=0; i < bookAscLines.size(); i++) {
      String bookAscLine=bookAscLines.get(i);
      Matcher matcher=compiledRegex.matcher(bookAscLine);
      if (matcher.find()) {
        String chapterPath=matcher.group();
        String chapterContent=IOHelper.readFile(currentPath.resolve(chapterPath));
        allAscChapters.append(chapterContent);
        allAscChapters.append("String_Node_Str");
        bookAscLines.remove(i);
      }
    }
    StringBuffer allAscContent=new StringBuffer();
    bookAscLines.forEach(content -> {
      allAscContent.append(content);
      allAscContent.append("String_Node_Str");
    }
);
    String docBookHeaderContent=docConverter.asciidocToDocbook(webEngine,allAscContent.toString(),true);
    String docBookChapterContent=docConverter.asciidocToDocbook(webEngine,allAscChapters.toString(),true);
    StringReader bookReader=new StringReader(docBookHeaderContent);
    Match rootDocument=$(new InputSource(bookReader));
    bookReader.close();
    bookReader=new StringReader(docBookChapterContent);
    Match chapterDocument=$(new InputSource(bookReader));
    bookReader.close();
    rootDocument.append(chapterDocument.find("String_Node_Str"));
    rootDocument.find("String_Node_Str").parents("String_Node_Str").each((context) -> {
      $(context).rename("String_Node_Str");
    }
);
    rootDocument.find("String_Node_Str").find("String_Node_Str").attr("String_Node_Str","String_Node_Str");
    StringBuilder builder=new StringBuilder();
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append(rootDocument.content());
    IOHelper.writeToFile(currentPath.resolve("String_Node_Str"),builder.toString(),CREATE,TRUNCATE_EXISTING);
    if (showIndicator) {
      indikatorService.completeCycle();
      asciiDocController.setLastConvertedFile(Optional.of(currentPath.resolve("String_Node_Str")));
    }
  }
 catch (  Exception ex) {
    logger.error(ex.getMessage(),ex);
  }
 finally {
    indikatorService.hideIndikator();
  }
}

Fixed version (ground truth):
public void generateDocbook(WebEngine webEngine,Path currentPath,boolean showIndicator){
  try {
    Path bookAsc=bookPathResolver.resolve(currentPath);
    if (Objects.isNull(bookAsc)) {
      IOHelper.writeToFile(currentPath.resolve("String_Node_Str"),"String_Node_Str",CREATE,TRUNCATE_EXISTING);
      return;
    }
    if (showIndicator)     indikatorService.startCycle();
    List<String> bookAscLines=Files.readAllLines(bookAsc);
    StringBuffer allAscChapters=new StringBuffer();
    for (int i=0; i < bookAscLines.size(); i++) {
      String bookAscLine=bookAscLines.get(i);
      Matcher matcher=compiledRegex.matcher(bookAscLine);
      if (matcher.find()) {
        String chapterPath=matcher.group();
        String chapterContent=IOHelper.readFile(currentPath.resolve(chapterPath));
        allAscChapters.append(chapterContent);
        allAscChapters.append("String_Node_Str");
        bookAscLines.remove(i);
      }
    }
    StringBuffer allAscContent=new StringBuffer();
    bookAscLines.forEach(content -> {
      allAscContent.append(content);
      allAscContent.append("String_Node_Str");
    }
);
    String docBookHeaderContent=docConverter.asciidocToDocbook(webEngine,allAscContent.toString(),true);
    String docBookChapterContent=docConverter.asciidocToDocbook(webEngine,allAscChapters.toString(),true);
    StringReader bookReader=new StringReader(docBookHeaderContent);
    Match rootDocument=$(new InputSource(bookReader));
    bookReader.close();
    bookReader=new StringReader(docBookChapterContent);
    Match chapterDocument=$(new InputSource(bookReader));
    bookReader.close();
    rootDocument.append(chapterDocument.find("String_Node_Str"));
    rootDocument.find("String_Node_Str").parents("String_Node_Str").each((context) -> {
      $(context).rename("String_Node_Str");
    }
);
    rootDocument.find("String_Node_Str").find("String_Node_Str").attr("String_Node_Str","String_Node_Str");
    rootDocument.find("String_Node_Str").forEach(elem -> {
      String arearefs=$(elem).attr("String_Node_Str");
      String[] cos=arearefs.split("String_Node_Str");
      if (cos.length > 1)       $(elem).attr("String_Node_Str",cos[cos.length - 1]);
    }
);
    StringBuilder builder=new StringBuilder();
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append("String_Node_Str");
    builder.append(rootDocument.content());
    IOHelper.writeToFile(currentPath.resolve("String_Node_Str"),builder.toString(),CREATE,TRUNCATE_EXISTING);
    if (showIndicator) {
      indikatorService.completeCycle();
      asciiDocController.setLastConvertedFile(Optional.of(currentPath.resolve("String_Node_Str")));
    }
  }
 catch (  Exception ex) {
    logger.error(ex.getMessage(),ex);
  }
 finally {
    indikatorService.hideIndikator();
  }
}