idea中jdk版本没设置好
1.File->Settings->Build,Execution,Deployment->Compiler->Java Compiler
设置合适的jdk版本
2.File->Project Structure->project
3.File->Project Structure->Modules
idea中jdk版本没设置好
1.File->Settings->Build,Execution,Deployment->Compiler->Java Compiler
设置合适的jdk版本
2.File->Project Structure->project
3.File->Project Structure->Modules