How to save the input of a Java dialog?

When I try to read or write to an external file in java. The program compiles to me but when the code is executed and I write the name of the file that I want that it reads, the program stays run but it does not show anything to me in screen.

import java.util.Scanner;
import javax.swing.*;
import java.io.*;
import java.io.FileReader;
import java.io.PrintWriter;

// Declared class ProjectPorStr
public class ProjectPorStr {
    // Declared Object Scanner; 
  static Scanner input = new Scanner(System.in);

// Declaring the metohod menu
// And declaring menu items.
 public static void menu (String productNamesList[]) {
    String test = "";

    do {
        test = JOptionPane.showInputDialog(null, "a. Add items\n b. Show items\n c. Remove items\n x. Exit");

        if (test.equals ("a")) {
            JOptionPane.showMessageDialog(null, "Added items");
        }
        else if (test.equals ("b")) {
            JOptionPane.showMessageDialog(null, "Showing items");
            JOptionPane.showMessageDialog(null, productNamesList);
        }
        else if (test.equals ("c")) {
            JOptionPane.showMessageDialog(null, "Delet the items");
        }
        else if (test.equals ("x")) {
            JOptionPane.showMessageDialog(null, "Thank you for user own system. See it soon!");
            System.exit(0);
        }
        else {
            JOptionPane.showMessageDialog(null, "Please try agen.");
        }
    }while(!test.equals("d"));
}   
    // Declaring the metohd call name
    // And declaring multiple variable
    // Reader, fileInput, fileOutput and the array name productNamesList has 50 items
    // Adding integer variable matchesCount, date, upcNumber, experDate, quantitySold, itemsPrices
    // Collect the data when the user enters the product number
    public static void name () {
        Scanner keyboard = new Scanner(System.in);
        FileReader reader;
        Scanner fileInput;
        PrintWriter fileOutput;
        String productNamesList [] = new String [30],
        product, strLine, namesOfInputFile, namesOfOuputFile;

        int matchesCount = 0, date, upcNumber, experDate, quantitySold, itemsPrices;

        JOptionPane.showInputDialog(null, "Name of the input file and add .txt: ");
        namesOfInputFile = keyboard.next();
        JOptionPane.showInputDialog(null, "Name of the output file and add .txt: ");
        namesOfOuputFile = keyboard.next();

        // Input try
        try {
            reader = new FileReader(namesOfInputFile);
            fileInput = new Scanner (reader);

            while (fileInput.hasNextLine()) {
                strLine = fileInput.nextLine();
                product = strLine;
                upcNumber = Integer.valueOf(strLine);

                if (productNamesList.equals ("b")) {
                    productNamesList[matchesCount] = product;
                    matchesCount += 1;
                } 
            }
            fileInput.close();
        }catch(IOException error) {
            System.out.print("File error " + error);
        }

        // Output try
        try {
            fileOutput = new PrintWriter(namesOfOuputFile);
            for (int i = matchesCount - 1; i >= 0; i --) {
                JOptionPane.showMessageDialog(null, "Name Product: " + productNamesList[i]);
                fileOutput.print(productNamesList[i]);
            }
            fileOutput.close();
        }catch(IOException error) {
            System.out.print("File error " + error);
        }
    }

    // The main function
    // Calling the matohd
  public static void main(String[] args) {

        ProjectPorStr myMenu = new ProjectPorStr();
        String[] menuList = {"Meet", "Fish", "Cake"};
        name();
  }
}

It would be a great help for me.