pom.xml中project.reporting.outputEncoding

参考文档位置：https://cwiki.apache.org/confluence/display/MAVENOLD/Reporting+Encoding+Configuration

Adding this element to the POM structure without breaking backward compatibility can only happen in a future version, yet to be defined (at least after Maven 3.0):

<project>

   ...

   <reporting>

     <outputEncoding>UTF- 8 </outputEncoding>

     ...

   </reporting>

   ...

</project>

---

For Maven 2.x, the value can be defined as an equivalent property:

<project>

   ...

   <properties>

     <project.reporting.outputEncoding>UTF- 8 </project.reporting.outputEncoding>

     ...

   </properties>

   ...

</project>

Thus plugins could immediately be modified to use   ${project.reporting.outputEncoding } expression, whatever Maven version is used.