Bookmarks in a pdf not going to the correct pages nor any page for that matter. Why is this happening?

Question

I'm using Netbeans and the iText pdf api. So I have the following method that creates a hashtable that can be inserted into a pdf. In this case they are image files that are to be placed in the pdf at the end of the document.

private HashMap<String, Object> newTmp = new HashMap<>(); //to generate bookmarks from images, another object is made
private ArrayList<HashMap<String, Object>> bookmarks = new ArrayList<>(); //an array list is instantiated for bookmarks to be saved

private void bookmarkGen(String imageList[]) {
int n = 0; //counter used to progress each bookmark.
    for (int i = 0; i < imageList.length; i++) {
        if (imageList[i] != null) {
            bookmarks.add(newTmp);
            newTmp.put("Title", imageList[i].substring(imageList[i].lastIndexOf("/"), imageList[i].lastIndexOf(".")));
            newTmp.put("Action", "GoTo");
            newTmp.put("Page", String.format("%d Fit", n++));
            System.out.print(n + "\n");
            System.out.print("Bookmark Added\n");
        }
    }
}

The next part of this process involves the following lines of code to input the bookmarks to the pdf.

    if (!bookmarks.isEmpty() && pdfcounter > 0) {
        copy.setOutlines(bookmarks);
        System.out.println("Bookmarks have been outlined");
    }

Whenever I do this, one of the bookmarks just go to one page and the rest don't have a page assigned. What am I doing wrong?

Answer 1

You create newTmp once and add it to your list multiple times, overwriting its entries each time. Thus, you eventually have a list containing many references to newTmp with the values set in the last iteration of the loop.

To fix this, move

private HashMap<String, Object> newTmp = new HashMap<>(); 

Into the loop.