Encapsulating Shiro Subject

Question

I would like to encapsulate Apache Shiro in a Servlet environment. I want to create MySecurityUtils and use Shiro SecurityUtils.getSubject in a static method. My question is whether this is a correct way to use SecurityUtils.getSubject method in a static method. Can this cause any problems in multithreaded servlet environment?

MySecurityUtils.java

import org.apache.shiro.subject.Subject;
import org.apache.shiro.SecurityUtils;

public class MySecurityUtils {

    public static MyUser getUser() {
        Subject currentUser = SecurityUtils.getSubject();
        MyUser myUser = new MyUser(currentUser);
        ...
    }
}

MyUser.java

public class MyUser {
   // ... constructors
   public boolean isPermitted(..) {subject.isPermitted(...)}
}

Answer 1

After feedback of Sotirios I changed my code as follows

 public class SecurityHelper {
     public static boolean isAuthenticated(){
      Subject currentUser = SecurityUtils.getSubject();
      return currentUser.isAuthenticated();
     }
     public static void checkPermission(String permissionCode){
          Subject currentUser = SecurityUtils.getSubject();
          currentUser.checkPermission(permissionCode);
     }
     public static void checkPermission(String... permissionCodes){
          Subject currentUser = SecurityUtils.getSubject();
          currentUser.checkPermissions(permissionCodes);
     }
     ... and so on

I encapsulate all application logic in a Helper class.