修改自定义realm

注意：如果你创建了一个用户，并为这个用户授予了一个角色，但这个角色并未关联任何的 授权字符串，那么调用数据库获得的结果是 List perms=[null]，此时 perms已经被初始化，里面只有一个属性null，使用判空的方法无法判别，此时继续遍历会报出空指针异常，此时应当添加判断条件 perms.get(0)!=null

// 自定义Realm
public class CustomerRealm extends AuthorizingRealm {
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principalCollection) {
        //获取身份信息
        String primaryPrincipal = (String) principalCollection.getPrimaryPrincipal();
        System.out.println("调用授权验证：" + primaryPrincipal);
        //根据主身份信息获取角色 和 权限信息
        UserService userService = (UserService) ApplicationContextUtils.getBean("userService");
        User user = userService.findRolesByUserName(primaryPrincipal);
        //授权角色信息
        if (!CollectionUtils.isEmpty(user.getRoles())){
            SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();
            user.getRoles().forEach(role -> {
                simpleAuthorizationInfo.addRole(role.getName());
                //权限信息
                List<Perms> perms = userService.findPermsByRoleId(role.getId());
                if(!CollectionUtils.isEmpty(perms)){
                    perms.forEach(perm -> {
                        simpleAuthorizationInfo.addStringPermission(perm.getName());
                    });
                }
            });
            return simpleAuthorizationInfo;
        }
        return null;
    }
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken authenticationToken) throws AuthenticationException {
        //根据身份信息
        String principal = (String) authenticationToken.getPrincipal();
        //在工厂中获取service对象
        UserService userService = (UserService) ApplicationContextUtils.getBean("userService");
        User user = userService.findByUserName(principal);
        if(!ObjectUtils.isEmpty(user)){
            return new SimpleAuthenticationInfo(user.getUsername(), user.getPassword(),
                       new MyByteSource(user.getSalt()), this.getName());
        }
        return null;
    }
}