....

examcloud-core-basic-service/src/main/java/cn/com/qmth/examcloud/core/basic/service/impl/SystemPropertyServiceImpl.java

@@ -84,6 +84,9 @@ public class SystemPropertyServiceImpl implements SystemPropertyService {
 	@Override
 	public Object get(String key) {
 		SysPropertyCacheBean sysPropertyCacheBean = systemPropertyCache.get(key);
+		if (null == sysPropertyCacheBean) {
+			return null;
+		}
 		return sysPropertyCacheBean.getValue();
 	}