Java：无效的源版本：9

Question

I have created a maven project in IntelliJ, I downloaded the dependencies that I need and I can see there are no errors in the code.

I am still getting this error even though I have set Java 8 in project in Project Settings

This is what my pom.xml looks like:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>multithreadedCalls</groupId>
    <artifactId>multithreadedCalls</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.10</version>
        </dependency>
    </dependencies>
</project>

Answer 1

Just change java version on the second screenshot

Answer 2

That's how I made it work.

File -> settings and then went to this window and updated compiler version from the dropdown.