Array - Comparing int

Question

I'm having issues with the code below, why am I not able to check if "if(Person[i][0] < 18)" I get error stating "Incomparable types".

I have found articles stating that I can use "if (Person[i][0].equals(18)), but how can I check if it is greater than?

    Object[][] Person = new Object[2][2];
    Person[0][0] = "John";
    Person[0][1] = new Integer(18);

    Person[1][0] = "Mike";
    Person[1][1] = new Integer(42);


    for(int i = 0; i < Person.length; i++)
    {
        System.out.print(Person[i][0]);
        System.out.print("\t" + Person[i][1] + "\t");

       if(Person[i][0] < 18)
      {
          System.out.print("18 or over");
      }    

        System.out.println();
    }  

Answer 1

您必须输入大小写的对象以整数形式，例如：

  if((int)Person[i][1] > 18)

Answer 2

It's extended version could be something like below. You might want to avoid string check. Go for Integer comparison only.

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
public class Codechef
{
    public static void main (String[] args) throws java.lang.Exception
    {
        Object[][] Person = new Object[2][2];
        Person[0][0] = "John";
        Person[0][1] = new Integer(18);

        Person[1][0] = "Mike";
        Person[1][1] = new Integer(42);


        for(int i = 0; i < Person.length; i++)
        {
            for(int j = 0; j < Person.length; j++)
            {
                System.out.print("\t" + Person[i][j] + "\t");

                if(Person[i][j] instanceof Integer)
                {
                    if((int)Person[i][j] > 18)
                    System.out.print("18 or over");
                }
            }
            System.out.println();
        }
    }
}

I would recommend you to use Map which could be the best solution for this. Check the code below.

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
public class Codechef
{
    public static void main (String[] args) throws java.lang.Exception
    {
        Map<String, Integer> person = new HashMap<>();
        person.put("John", 18);
        person.put("Tim", 32);
        person.put("Georges", 39);
        person.put("Mike", 45);
        person.put("Vikor", 17);
        //interate this map
        Iterator<Map.Entry<String,Integer>> itr = person.entrySet().iterator();
        while(itr.hasNext()){
            Map.Entry<String,Integer> p = itr.next();
            System.out.print(p.getKey() +" - "+p.getValue());
            if(p.getValue() >= 32)
                System.out.print("\t 32 or over");
           System.out.println();
        }

    }
}

It might be helpful for someone.