Apache POI - Replace content in XWPFParagraph

// Before using the function, I'm sure that: paragraph.getText().contains("<#" + tag + "#>") == true
private static void editParagraphWithData(XWPFParagraph paragraph, String tag, String remplacement) {
    int currentRun = 0;
    List<Integer> runsToRemove = new LinkedList<Integer>();
    StringBuilder newText = new StringBuilder();
    int runToEdit = 0;
    String surroundedTag = "<#" + tag + "#>";

    // Until we didn't find the tag
    while (!newText.toString().contains(surroundedTag)) {

        // Until we didn't find the first corresponding run
        while (paragraph.getRuns().size() > currentRun  && !paragraph.getRuns().get(currentRun).text().contains("<#")) {
            currentRun++;
        }

        runToEdit = currentRun;
        newText.append(paragraph.getRuns().get(runToEdit).text());

        currentRun++;

        // Until we didn't find the end of the tag if it's divided in many runs
        while (paragraph.getRuns().size() > currentRun && !paragraph.getRuns().get(currentRun).text().contains("#>")) {
            runsToRemove.add(currentRun);
            newText.append(paragraph.getRuns().get(currentRun).text());
            currentRun++;
        }

        // If we didn't find the right tag
        if (!newText.toString().contains(surroundedTag)) {
            runsToRemove.clear();
            newText = new StringBuilder();
        }
    }

    // Replace the tag
    paragraph.getRuns().get(runToEdit).setText(newText.toString().replaceAll(surroundedTag, remplacement), 0);

    // Remove the remaining tags if we need to (in reverse order)
    Collections.reverse(runsToRemove);
    for (Integer runToRemove : runsToRemove) {
        paragraph.removeRun(runToRemove);
    }
}