Input into 2d array table

Question

code is not right :( will repost.
Edited by: jettaz on May 24, 2008 3:43 PM
I have initialized a 14x4 array and filled it myself, while allowing the user to further input 4 more rows if he so wishes.
The array table is 2d for an inventory, sorted by type and brand.
try
plainWrapString = JOptionPane.showInputDialog("Please enter Plain Wrap type:");
brandAString = JOptionPane.showInputDialog("Enter serial for brand A:");
brandCString = JOptionPane.showInputDialog("Enter serial for brand C:");
brandXString = JOptionPane.showInputDialog("Enter serial for brand X:");
for(rowsInteger = 0; rowsInteger < 14; rowsInteger++)
if(plainWrapString.equalsIgnoreCase(inventoryArray[rowsInteger][columnInteger]))
throw new IllegalArgumentException("Duplicate found! Please retry.");
inventoryArray[rowsInteger][columnInteger] = plainWrapString;First of all, my try... catch statement, doesn't catch even when plainWrapString input is a copy of the already entered data in the array table. I had it working okay, though, before I attempt to get the user tp further input more data corresponding to the plainWrapString's row. I'm not sure if this works for inputting the following data according to brands.
for (columnInteger = 0; columnInteger < 4; columnInteger ++)
inventoryArray[rowsInteger][columnInteger] = brandAString;
columnInteger = 0; // resets columnInteger back to zero to continue filling next
                            // column in array?
for (columnInteger = 0; columnInteger < 4; columnInteger++)
inventoryArray[rowsInteger][columnInteger] = brandXString;
columnInteger = 0;
for (columnInteger = 0; columnInteger < 4; columnInteger++)
inventoryArray[rowsInteger][columnInteger] = brandCString;
selectionDropMenu[rowsInteger] = plainWrapString; // something extra to add to a
                                                                           // drop menu
catch(IllegalArgumentException error)
JOptionPane.showMessageDialog(null, error.getMessage());
}Any help is appreciated :)
Edited by: jettaz on May 24, 2008 3:46 PM
Edited by: jettaz on May 24, 2008 4:20 PM

Answer 1

A HashMap would be a better way to ensure that you have unique elements. This approach will allow you to get away from using exception. I have attached two classes. I have assumed that you only want to store one type, but each type can have many brands. The types will be unique but the brands can be duplicates. The brand object counts the number of duplicate entries. An additional benefit of this approach is that you do not need to know the size of your collection before hand.
The test class contains the main() method.
import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;
public class TestClass{
     private HashMap<String, Brand> type = new HashMap<String, Brand>();
     public TestClass(){
     public void addTypeAndBrand(String typeName, String brandName){
          Brand b = type.get(typeName);
          if(b==null){
               type.put(typeName, new Brand(brandName));
          }else{
               b.addBrand(brandName);
     public void listTypeAndBrand(){
          Set<String> types = type.keySet();
          SortedSet<String> sortedTypes = new TreeSet<String>(types);
          Iterator<String> typeIter = sortedTypes.iterator();
          Brand b = null;
          String typeName = "", brandName = "";
          int frequency=0;
          while(typeIter.hasNext()){
               typeName = typeIter.next();
               b = type.get(typeName);
               Set<String> brands = b.getKeys();
               SortedSet<String> sortedBrands = new TreeSet<String>(brands);
               Iterator<String> brandIter = sortedBrands.iterator();
               while(brandIter.hasNext()){
                    brandName = brandIter.next();
                    frequency = b.getCount(brandName);
                    System.out.println("Type: " + typeName + ",     Brand: " + brandName + ",     Brand Count: " + frequency);
     public static void main(String[] arg){
          TestClass test = new TestClass();
          test.addTypeAndBrand("Japan", "Toyota");
          test.addTypeAndBrand("Japan", "Honda");
          test.addTypeAndBrand("Japan", "Honda");
          test.addTypeAndBrand("USA", "Ford");
          test.addTypeAndBrand("USA", "Chevy");
          test.addTypeAndBrand("USA", "Dodge");
          test.listTypeAndBrand();
}The Brand class is:
import java.util.HashMap;
import java.util.Set;
public class Brand {
     private HashMap<String, Frequency> brand = new HashMap<String, Frequency>();
     public Brand(String brandName){
          brand.put(brandName, new Frequency());
      * Add brand to HashMap. If brand does not already exist, add brand to HashMap.
      * Otherwise increment count of brand.
      * @param newBrand brand to be added to HashMap
     public void addBrand(String newBrand){
          Frequency freq = brand.get(newBrand);
          if(freq==null){
               brand.put(newBrand, new Frequency());
          }else{
               freq.add();
     public Set<String> getKeys(){
          return brand.keySet();
     public int getCount(String key){
          Frequency f = brand.get(key);
          return f.getFrequency();
      * Inner class for frequency counts.
     class Frequency{
          private int total;
          public Frequency(){
               total = 1;
          public void add(){
               total++;
          public int getFrequency(){
               return total;
}The output I get is:
Type: Japan, Brand: Honda, Brand Count: 2
Type: Japan, Brand: Toyota, Brand Count: 1
Type: USA, Brand: Chevy, Brand Count: 1
Type: USA, Brand: Dodge, Brand Count: 1
Type: USA, Brand: Ford, Brand Count: 1