设置默认新建项目JDK1.8
1.找到自己Maven地址conf包下Settings.xml配置
2.在里面属性里面加入下面配置

<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>