mvn compile报编译版本错误

mvn compile报编译版本的错误，加入如下plugin即可解决

<plugin>
   <artifactId>maven-compiler-plugin</artifactId>
   <configuration>
      <source>1.7</source>
      <target>1.7</target>
      <encoding>UTF-8</encoding>
   </configuration>
</plugin>