update NPE

src/main/java/cn/com/qmth/examcloud/app/service/impl/CoreAuthServiceImpl.java

@@ -391,9 +391,14 @@ public class CoreAuthServiceImpl implements CoreAuthService {
             if (response.isSuccessful()) {
                 //获取用户信息
                 UserInfo userInfo = of(bodyStr);
+                if(userInfo == null){
+                    log.warn("Login response is " + bodyStr);
+                    return new Result<>().error("登录失败！");
+                }
+
                 return new Result().success(userInfo);
             } else {
-                log.warn("Http response is " + bodyStr);
+                log.warn("Login response is " + bodyStr);
                 ResBody body = new JsonMapper().parseJson(bodyStr, ResBody.class);
                 if (body != null && body.getCode() != null) {
                     return new Result().error(body.getDesc());
@@ -402,13 +407,17 @@ public class CoreAuthServiceImpl implements CoreAuthService {
             }
         } catch (Exception e) {
             log.error(e.getMessage(), e);
-            return new Result().error("登录异常！");
+            return new Result().error("登录失败！");
         }
 	}
 	
 	private UserInfo of(String bodyStr) {
 		JSONObject job=JSONObject.parseObject(bodyStr);
 		JSONObject content=job.getJSONObject("content");
+        if(content == null){
+            return null;
+        }
+
 		UserInfo userInfo = new UserInfo();
 		userInfo.setKey(content.getString("key"));
 		userInfo.setUserId(content.getLong("userId"));