In this post we focuses on adding two matrices.Before adding two matrices we need two matrices of same order.i.e is number of rows,columns in matrix 1 should be equaled to number of rows,columns in matrix 2.The procedure for adding two matrix is:
1. Input:Take two,matrix of same order from the user,can be of different elements.
2. Procedure:For summation of two matrix we need to add the elements of the corresponding position and store them in the same position.
3. Display:After the summation we display the result stored in the matrix.
By following the above steps we can write a simple code:

import java.util.*;
class addition
{
 int n,i,j;
 void setdata()
   {
      Scanner in = new Scanner(System.in);
      int[][] mat1 = new int[n+1][n+1];
      int[][] mat2 = new int[n+1][n+1];
      int[][] resltmat = new int[n+1][n+1]; 
      System.out.println("Enter the elements of 1 matrix:"); 
      for(i=1;i < n+1;i++)
       {
          for(j=1;j < n+1;j++)
           {
             System.out.println("Enter the element of "+ i +" row "+ j +" column:");
             mat1[i][j] = in.nextInt();
            }// end of j loop
         }//  end of i loop
      System.out.println("Enter the elements of 2 matrix:"); 
      for(i=1;i < n+1;i++)
       {
         for(j=1;j < n+1;j++)
           {
             System.out.println("Enter the element of "+ i +" row "+ j +" column:");
             mat2[i][j] = in.nextInt();
            }// end of j loop
         }// end of i loop
     System.out.println("Resultant matrix is:\n");
      for(i=1;i < n+1;i++)
       {
         for(j=1;j < n+1;j++)
           {
             resltmat[i][j] = mat1[i][j]+mat2[i][j];          //adds the elements of the matrxi 1,2
             System.out.print(resltmat[i][j] + "  ");
            }
             System.out.print("\n\n");
         }
       
     }
   
}
class matadd
{
   public static void main(String arg[])
     {
       Scanner in = new Scanner(System.in);
       addition ob = new addition();
       System.out.print("Enter the order of the matrix you need to enter:");
       ob.n=in.nextInt();
       ob.setdata();
    }
}

The output of the above program is:

You can download the source code.