Here is the code the 6th period class wrote:

import java.util.Scanner;

/**
 * Write a description of class Demo here.
 *
 * @author (your name)
 * @version (a version number or a date)
 */
public class Demo
{
    // instance variables - replace the example below with your own
    private int x;

    /**
     * Constructor for objects of class Demo
     */
    public Demo()
    {
		
        // Rectangle with Hole
        Scanner scan = new Scanner(System.in);
        int x = scan.nextInt();
        int y = scan.nextInt();
        //y = y*2;
        
        for(int j = 0; j < y; j++){
            if (j == 0){
                //Top
                for(int i = 0; i < x; i++){                
                    System.out.print("X");                    
                }  
            } else if(j == ( y - 1 )){
                // Bottom
                for(int i = 0; i < x; i++){                
                    System.out.print("X");                    
                } 
            } else{
                // Middle
                System.out.print("X");
                for(int i = 1; i < (x-1); i++){                
                    System.out.print(" ");                    
                } 
                System.out.print("X");
            }
            System.out.println("");            
        }
        
        
    }

    
    //Double Y Height
	Scanner scan = new Scanner(System.in);
        int x = scan.nextInt();
	int y = scan.nextInt();
        while(j < 2*y){
         for(int i = 0; i < x; i++){                
                   System.out.print("X");                    
                }  
            j++;
           System.out.println("");
       }
    

    // Full Rectangle
	Scanner scan = new Scanner(System.in);
        int x = scan.nextInt();
	int y = scan.nextInt();
        while(j < y){
            for(int i = 0; i < x; i++){                
                    System.out.print("X");                    
                }  
            j++;
            System.out.println("");
        }
    


    // Fix #2
    
     Scanner scan = new Scanner(System.in);
        int x = scan.nextInt();
      for(int i = 1; i <= x; i++){
            System.out.print("X");
        }
     
    
    // Fix #1
    
     Scanner scan = new Scanner(System.in);
        int x = scan.nextInt();
      for(int i = 0; i < x; i++){
            System.out.print("X");
        }
     
    
    // Off by 1
    
     Scanner scan = new Scanner(System.in);
        int x = scan.nextInt();
      for(int i = 0; i <= x; i++){
            System.out.print("X");
        }
     
    

}