(Easy) Robot Bounded in Circle

class Solution {
    public boolean isRobotBounded(String instructions) {
        
        int len = instructions.length();
        
        int x = 0;
        
        int y = 0;
        
        int dir = 0;
        
        for (int i = 0; i< len; i++){
            
            if(instructions.charAt(i) == 'R'){
                
                if(dir ==0 ){
                    
                    dir = 3;
                }
                
                else {
                    
                    dir --;
                }
                
                
            }
        
            else if(instructions.charAt(i) =='L'){
                if(dir ==3){
                    
                    dir = 0;
                }
                
                else{
                
                    dir ++;
                }
                
            }
            
            else{
                
                switch(dir){
                    
                    case 0: y++; break;
                    case 1: x--; break;
                    case 2: y--; break;
                    case 3: x++; break;
                }
            }
                
        }
        
        if(x==0 && y==0){
            return true;
        }
        
        if(dir!=0){
            return true;
        }
        
        return false;
        
    }
}