An illegal reflective access operation has occurred_illegal reflective access by com.google.inject.int

现象 

idea启动项目时出现警告：

"/Applications/IntelliJ IDEA.app/Contents/jbr/Contents/Home/bin/java" ...
Connected to the target VM, address: '127.0.0.1:62251', transport: 'socket'
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$1 (file:/Users/lizz/.m2/repository/com/google/inject/guice/4.1.0/guice-4.1.0.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

原因分析

错误提示：com.google.inject.internal.cglib.core.$ReflectUtils$1访问了java.lang.ClassLoader类。

因为JDK9的新特性模块系统(module system)对jdk中的模块进行了反射检查，对于反射了jdk中的类的操作进行警告。

处理办法

方法一：降低jdk版本

将idea中的项目运行环境从高版本调整为JDK8即可,如果moudle格式，可能还需要将每个moudle单独设置。

File>Project Structure>Project Settings>Project>Project SDK.

方法二：开放访问权限

JDK9+可以使用启动参数中增加“--add-opens <package>/<class>=ALL-UNNAMED”的方法允许其他模块访问。

在RUN>Edit Configurations>VM options 中增加参数，如：

--add-opens java.base/java.lang=ALL-UNNAMED  --add-opens java.base/java.util=ALL-UNNAMED  --add-opens java.desktop/java.awt.font=ALL-UNNAMED

--add-opens java.base/java.lang=ALL-UNNAMED  --add-opens java.base/java.util=ALL-UNNAMED  --add-opens java.base/java.lang.reflect=ALL-UNNAMED  --add-opens java.base/java.text=ALL-UNNAMED --add-opens java.desktop/java.awt.font=ALL-UNNAMED