class ReversePages
        extends AbstractTool {

    static {
        addVersion(
                "$Id: ReversePages.java 3271 2008-04-18 20:39:42Z xlv $");
    }

    FileArgument destfile = null;

    /**
     * Constructs a ReversePages object.
     */
    public ReversePages() {
        menuoptions = MENU_EXECUTE | MENU_EXECUTE_SHOW;
        FileArgument inputfile = null;
        inputfile = new FileArgument(this, "srcfile",
                "The file you want to reorder", false,
                new PdfFilter());
        arguments.add(inputfile);
        destfile = new FileArgument(this, "destfile",
                "The file to which the reordered version of the original PDF has to be written", true,
                new PdfFilter());
        arguments.add(destfile);
        inputfile.addPropertyChangeListener(destfile);
    }

    /**
     * Take pages from an existing PDF and copy them in reverse order into a new PDF.
     *
     * @param args String[]
     */
    public static void main(String[] args) {
        ReversePages tool = new ReversePages();
        if (args.length < 2) {
            System.err.println(tool.getUsage());
        }
        tool.setMainArguments(args);
        tool.execute();
    }

    /**
     * @see com.lowagie.toolbox.AbstractTool#createFrame()
     */
    protected void createFrame() {<FILL_FUNCTION_BODY>}

    /**
     * @see com.lowagie.toolbox.AbstractTool#execute()
     */
    public void execute() {
        try {
            if (getValue("srcfile") == null) {
                throw new InstantiationException("You need to choose a sourcefile");
            }
            File src = (File) getValue("srcfile");
            if (getValue("destfile") == null) {
                throw new InstantiationException(
                        "You need to choose a destination file");
            }
            File dest = (File) getValue("destfile");

            // we create a reader for a certain document
            PdfReader reader = new PdfReader(src.getAbsolutePath());
            System.out.println("The original file had " + reader.getNumberOfPages() +
                    " pages.");
            int pages = reader.getNumberOfPages();
            ArrayList<Integer> li = new ArrayList<>();
            for (int i = pages; i > 0; i--) {
                li.add(i);
            }
            reader.selectPages(li);

            System.err.println("The new file has " + pages + " pages.");
            Document document = new Document(reader.getPageSizeWithRotation(1));
            PdfCopy copy = new PdfCopy(document,
                    new FileOutputStream(dest.getAbsolutePath()));
            document.open();
            PdfImportedPage page;
            for (int i = 0; i < pages; ) {
                ++i;
                System.out.println("Processed page " + i);
                page = copy.getImportedPage(reader, i);
                copy.addPage(page);
            }

            PRAcroForm form = reader.getAcroForm();
            if (form != null) {
                copy.copyAcroForm(reader);
            }
            document.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * @param arg StringArgument
     * @see com.lowagie.toolbox.AbstractTool#valueHasChanged(com.lowagie.toolbox.arguments.AbstractArgument)
     */
    public void valueHasChanged(AbstractArgument arg) {
        if (internalFrame == null) {
            // if the internal frame is null, the tool was called from the command line
            return;
        }

        if (destfile.getValue() == null && arg.getName().equalsIgnoreCase("srcfile")) {
            String filename = arg.getValue().toString();
            String filenameout = filename.substring(0, filename.indexOf(".",
                    filename.length() - 4)) + "_out.pdf";
            destfile.setValue(filenameout);
        }
    }

    /**
     * @return File
     * @throws InstantiationException on error
     * @see com.lowagie.toolbox.AbstractTool#getDestPathPDF()
     */
    protected File getDestPathPDF() throws InstantiationException {
        return (File) getValue("destfile");
    }

}

        internalFrame = new JInternalFrame("ReversePages", true, false, true);
        internalFrame.setSize(300, 80);
        internalFrame.setJMenuBar(getMenubar());
        System.out.println("=== ReversePages OPENED ===");
    
<methods>public void <init>() ,public void actionPerformed(java.awt.event.ActionEvent) ,public abstract void execute() ,public ArrayList<com.lowagie.toolbox.arguments.AbstractArgument> getArguments() ,public javax.swing.JInternalFrame getInternalFrame() ,public javax.swing.JMenuBar getMenubar() ,public java.lang.String getUsage() ,public java.lang.Object getValue(java.lang.String) throws java.lang.InstantiationException,public void setArguments(ArrayList<com.lowagie.toolbox.arguments.AbstractArgument>) ,public void setInternalFrame(javax.swing.JInternalFrame) ,public void setMainArguments(java.lang.String[]) ,public void setMenubar(javax.swing.JMenuBar) ,public abstract void valueHasChanged(com.lowagie.toolbox.arguments.AbstractArgument) <variables>public static final int MENU_EXECUTE,public static final int MENU_EXECUTE_PRINT,public static final int MENU_EXECUTE_PRINT_SILENT,public static final int MENU_EXECUTE_SHOW,protected ArrayList<com.lowagie.toolbox.arguments.AbstractArgument> arguments,private java.awt.Desktop awtdesktop,protected javax.swing.JInternalFrame internalFrame,private javax.swing.JMenuBar menubar,protected int menuoptions,public static ArrayList<java.lang.String> versionsarray