Creating two Dimensional array with existing arrays in java

Question

I have four arrays of strings and I would like to create a two dimensional array of 3 columns and dynamic rows.

the arrays are like:

String[] first_name;
String[] last_name;
String[] unit;
String[] phone_number;


Object[][] obj = new Object[first_name.length()][3]

My problem is how do I achieve something like this:

obj = {first_name[index] + " " + last_name[index], unit[index], phone_number[index]}

Please help out!!!

Answer 1

I am assuming that by dynamic rows you mean that it depends on the number of elements in the first_name array.

So you could simply iterate:

String[][]obj = new String[first_name.length][3];

for (int i = 0; i < first_name.length; i++)
{
  obj[i][0] = first_name[i] + " " + last_name[i];
  obj[i][1] = unit[i];
  obj[i][2] = phone_number[i];
}

However, this approach is not very good. You should consider creating an object for example named Employee which as the 3 fields, and then you just have an array of Employee

For example:

public class Employee
{
  String name;
  String unit;
  String phoneNumber;

  public Employee(String name, String unit, String phoneNumber)
  {
     //... rest of constructor to copy the fields
  }

  //... setters and getters
}

And then you just have:

Employee[] employees = new Employee[first_name.length];

for (int i = 0; i < first_name.length; i++)
{
   employees[i] = new Employee(first_name[i] + " " + last_name[i], unit[i], phone_number[i]);
}