Matrix rotate

GIven a 2D NxN matrix, visualize it as concentric circles. You have to find the rotated matrix where each element in the circle is rotated by 1 position layer by layer in an alternate clockwise and anticlockwise direction.

Sample Input:

4

2 3 4 5

1 6 7 8

4 2 1 9

5 3 2 4

Sample Output:

1 2 3 4 

4 7 1 5 

5 6 2 8 

3 2 4 9

My Code:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.lang.Math;


public class Solution {


public static void main(String[] args) {


int N =0;
int a[][],b[][];

BufferedReader br = 
         new BufferedReader(new InputStreamReader(System.in));
try {
String s = br.readLine();
N = Integer.parseInt(s);
a = new int[N][N];

for(int i=0;i<N;i++)
{
s = br.readLine();
String tmp[] =s.split(" ");
for(int j=0;j<N;j++){
a[i][j]= Integer.parseInt(tmp[j]);
//System.out.print(a[i][j]+" ");
}
//System.out.println();
}
int dist = 0;
int ii,jj;
for(int i=0;i<N;i++){
for(int j=0;j<N;j++){
dist = Math.min(Math.min(i,N-1-i),Math.min(j,N-1-j));
ii=i;jj=j;
if(dist%2==0){ // do clockwise rotation
if(dist==i){// top row
jj = j-1;
ii = i;
if(jj<dist){
jj = j;
ii = i+1;
}
}
else if(dist==j){// left col
jj = j;
ii = i+1;
if((N-1-ii)<dist){
jj = j+1;
ii = i;
}
}
else if(dist==(N-1-i)){// bottom row
jj = j+1;
ii = i;
if((N-1-jj)<dist){
jj = j;
ii = i-1;
}
}
else if(dist==(N-1-j)){// right col
jj = j;
ii = i-1;
if(ii<dist){
jj = j-1;
ii = i;
}
}
}
else{ // anti clockwise
if(dist==i){// top row
jj = j+1;
ii = i;
if((N-1-jj)<dist){
jj = j;
ii = i+1;
}
}
else if(dist==j){// left col
jj = j;
ii = i-1;
if(ii<dist){
jj = j+1;
ii = i;
}
}
else if(dist==(N-1-i)){// bottom row
jj = j-1;
ii = i;
if(jj<dist){
jj = j;
ii = i-1;
}
}
else if(dist==(N-1-j)){// right col
jj = j;
ii = i+1;
if((N-1-ii)<dist){
jj = j-1;
ii = i;
}
}
}
if(Math.min(ii,N-1-ii)<dist){
ii=i;
}
else if(Math.min(jj,N-1-jj)<dist){
jj=j;
}
System.out.print(a[ii][jj]+" ");
}
System.out.println();
}

} catch (IOException e) {
e.printStackTrace();
}


}


}