Eclipse JDK Version Settings

1 Java Build Path (Project Authoring Environment Configuration):

Right-click on the project, properties, Java build Path, Libraries, select JRE System Library, Edit, select the desired JDK version;
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2 Select the compiler for a single project:

Right-click on the project, properties--Java compiler, binding project-level compiler type;

3 Modify the Pom.xml configuration file for the MAVEN project (should be the JDK compiler for selecting the project, with the highest priority):

<plugins>        <plugin>            <artifactId>maven-compiler-plugin</artifactId>            < configuration>              <source>1.8</source>              <target>1.8</target>          </configuration>        </plugin>            </plugins>

Eclipse JDK Version Settings