标记"module“出现语法错误，应为接口

Question

在vscode中的java 9项目中出现以下错误。代码在maven上构建并成功执行。语法错误突出显示是唯一的问题

vscode-spring-boot日志：

Activating 'vscode-spring-boot' extension
Found java exe: C:\Program Files\Java\jdk-10\bin\java.exe
isJavaEightOrHigher => true
Redirecting server logs to C:\Users\USER1\AppData\Local\Temp\vscode-spring-boot-1531299333218.log
ERR: Redirecting log output to: C:\Users\USER1\AppData\Local\Temp\vscode-spring-boot-1531299333218.log
ERR: 

连接到端口45556上的子进程

Language support logs:
WARNING: Using incubator modules: jdk.incubator.httpclient
[Error - 2:25:48 PM] Jul 11, 2018, 2:25:38 PM Error occured while building workspace. Details: 
message: Syntax error on token "module", interface expected;code: 1610612940
message: Syntax error on token ".", , expected;code: 1610612940
message: Syntax error on token "module", interface expected;code: 1610612940
message: The project was not built since the source file /jdt.ls-java-project/src/com/demo/App.java could not be read;code: 0

Answer 1

该项目是一个用java9编写的hello world maven项目，如果没有添加这3个属性条目，maven插件默认使用java1.5。在pom.xml中添加这些属性并构建项目后，问题就解决了。

<maven.compiler.source>1.9</maven.compiler.source>
<maven.compiler.target>1.9</maven.compiler.target>
<maven.compiler.release>9</maven.compiler.release>