Box pattern made of Xs and Os in java

I'm trying to make a box pattern in java with a pattern that looks like

xoxox
o   x
oxoxo

I can get close with alternating x and o on the top and bottom, but there is a line of Os in between that I'm struggling to get rid of. Here is my code so far:

public static String textBoxString(int rows, int cols, char c1, char c2) {
		char temp = 0;
		for (int i = 1; i <= rows; i++) {
			for (int j = 1; j <= cols; j++) {
				if (i == 1 || i == rows) {
					System.out.print(c1);
					temp = c1;
				}
				if (temp == c1) {
					System.out.print(c2);
					
				}
				else {
					System.out.print(" ");
				}
			}
			System.out.println();

		}
		String sideString = Integer.toString(rows, cols);
		return sideString;
	}

Outputs:

xoxoxoxoxo
ooooo
xoxoxoxoxo

Here is an alternate implementation that uses a repeat() method to reduce repetitive code.

This code correctly prints alternating characters around the border. See tests at the end for proof that it works for any combination of odd/even numbers of rows and columns.

Solution for Java 11+:

public static void textBoxString(int rows, int cols, char c1, char c2) {
	System.out.println((String.valueOf(c1) + c2).repeat(cols / 2 + 1).substring(0, cols));
	String spaces = " ".repeat(cols - 2);
	for (int i = 2; i < rows; i++)
		System.out.println((i % 2 == 0 ? c2 : c1) + spaces + ((i + cols) % 2 == 0 ? c1 : c2));
	System.out.println((rows % 2 == 0 ? String.valueOf(c2) + c1 : String.valueOf(c1) + c2).repeat(cols / 2 + 1).substring(0, cols));
}

Same logic, but for any Java version, using a local repeat() helper method:

public static void textBoxString(int rows, int cols, char c1, char c2) {
	System.out.println(repeat(String.valueOf(c1) + c2, cols / 2 + 1).substring(0, cols));
	String spaces = repeat(" ", cols - 2);
	for (int i = 2; i < rows; i++)
		System.out.println((i % 2 == 0 ? c2 : c1) + spaces + ((i + cols) % 2 == 0 ? c1 : c2));
	System.out.println(repeat(rows % 2 == 0 ? String.valueOf(c2) + c1 : String.valueOf(c1) + c2, cols / 2 + 1).substring(0, cols));
}
private static String repeat(String s, int count) {
	StringBuilder buf = new StringBuilder();
	for (int i = 0; i < count; i++)
		buf.append(s);
	return buf.toString();
}

Tests

textBoxString(3, 5, 'x', 'o');
textBoxString(4, 5, 'x', 'o');
textBoxString(4, 6, 'x', 'o');
textBoxString(5, 6, 'x', 'o');

Outputs

xoxox
o   o
xoxox

xoxox
o   o
x   x
oxoxo

xoxoxo
o    x
x    o
oxoxox

xoxoxo
o    x
x    o
o    x
xoxoxo

This flow will solve your problem :

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

// The main method must be in a class named "Main".
class Main {
    public static void main(String[] args) {
                var result = textBoxString(4,6,'x','o');
        System.out.println("Hello world!");
    }
    
      
    public static String textBoxString(int rows, int cols, char c1, char c2) {
        char temp = 0;
        for (int i = 1; i <= rows; i++) {
            for (int j = 1; j <= cols; j++) {
                char toPrint = j%2==0?c1:c2;
                boolean isEmpty=true;
                if ((i == 1 || i == rows) || (i >1 && i < rows &&(j==1 || j==cols))) {
                    isEmpty=false;
                }
                
                
                if (!isEmpty) {
                    System.out.print(toPrint);
                    
                }
                else {
                    System.out.print(" ");
                }
            }
            System.out.println();

        }
        String sideString = Integer.toString(rows, cols);
        return sideString;
    }
}

I hope you need something like this

    public static String textBoxString(int rows, int cols, char c1, char c2) {
        char temp;
        for (int i = 1; i <= rows; i++) {
            for (int j = 1; j <= cols; j++) {
                if (1 == i || rows == i) {
                    System.out.print(c1);
                    System.out.print(c2);
                } else if (1 == j) {
                    System.out.print(c1 + " ");
                } else if (cols == j) {
                    System.out.print(" " + c2);
                } else {
                    System.out.print("  ");
                }
            }
            temp = c1;
            c1 = c2;
            c2 = temp;
            System.out.println();
        }
        return Integer.toString(rows, cols);
    }

I'd write it as:

  public static String textBoxString(int rows, int cols, char c1, char c2) {
    String box = "";
    boolean firstChar = true;
    for(int row=1; row<=rows; row++){
      for(int col=1; col<=cols; col++) {
        box = box + ((row==1 || row==rows || col==1 || col==cols) ? (firstChar ? c1 : c2) : " ");
        firstChar = !firstChar;
      }
      box = box + System.lineSeparator();
    }
    return box;
  }