搜索profiles

在里面添加配置即可

    <profile>
         <id>jdk-1.8</id>
         <activation>
             <activeByDefault>true</activeByDefault>
             <jdk>1.8</jdk>
         </activation>
         <properties>
             <maven.compiler.source>1.8</maven.compiler.source>
             <maven.compiler.target>1.8</maven.compiler.target>
             <maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion>
         </properties>
    </profile>