How can I delete a row in a 2d Array.

[mine0926]

Hi, I have to check for a duplicate entry and if found duplicate entry I have to add its quantity and delete the latter then

I use two(2) for loop to do this.

 private void checkDupEntry(Object[][] mat_toUse)
 {   Object matID_ToCheck = "";
     int qty = 0;

    for(int intMat = 0; intMat < mat_toUse.length; intMat++)
    {   matID_ToCheck = mat_toUse[intMat][0];
        qty = Integer.parseInt(mat_toUse[intMat][1].toString());

        for(int intCheck = intMat; intCheck < mat_toUse.length; intCheck++)
        {   if(matID_ToCheck.equals(mat_toUse[intCheck][0]))
            {   qty += Integer.parseInt(mat_toUse[intCheck][1].toString());
                //Delete 2D array
            }

        }
    }
 }

Thanks,
geje

[KevinWorkman]

What have you tried? What do you want to happen when you delete that row? Do you want the other contents to shift, or should that row just be empty? Do you have to use arrays, or can you use Lists?

[Eranga]

Did you end up with an error?

[mine0926]

Here is what I tried so far:

private void checkDupEntry()
{        Object[][] arrMat = {{"A001", 1}, {"A001", 1}, {"A001", 1},
        {"A002", 1}, {"A002", 1}, {"A003", 1}};

        Object matToCheck = "";
        
        int qty = 0;
        for(int intMat = 0; intMat < arrMat.length; intMat++)
        {   //Loop again to check for the same Material
            if(arrMat[intMat][0] != null )
            {   matToCheck = arrMat[intMat][0];
                qty = Integer.parseInt(arrMat[intMat][1].toString());

                //intMat + 1 so that it will not check itself
                for(int intCheck = intMat + 1; intCheck < arrMat.length; intCheck++)
                {   if( matToCheck.equals(arrMat[intCheck][0])   )
                    {   System.out.println(intCheck);
                        qty += Integer.parseInt(arrMat[intCheck][1].toString());
                        arrMat[intCheck][0] = null;
                        arrMat[intCheck][1] = null;
                    }
                }

                arrMat[intMat][1] = qty;

            }
        }
        Object[] colNames = {"MATERIAL", "QTY"};
        DefaultTableModel dtm = new DefaultTableModel(arrMat, colNames);
        jTable1.setModel(dtm);
}

I just set the value of duplicate values to null. These will not delete the row so do I have to use another array and us if else statement to eliminate arrays with null value? Is this the only way to check and delete the Row in an array?

I also try ArrayList and Lists but I cannot simply pass arrMat. I think ArrayList or Lists is asking me for a Collection and not an Object[][].

Thanks,
geje

[Eranga]

null not leads the idea of empty. Even you delete what you've really done was set the value to null. If you want to do this with arrays, yes on each item deletion you have to define a new array and assign values with the new size of the array.

Actually with arrays you can do that, once you remove an element simply adjust the size and ordered rest of the elements in the array.