解决Maven web 项目 Cannot detect Web Project version. Please specify version of Web Project through ... 的错误

Cannot detect Web Project version. Please specify version of Web Project through <version> configuration property of war plugin. E.g.: <plugin> <artifactId>maven-war-plugin</artifactId> <configuration> <version>3.0</version> </configuration> </plugin>

<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.4</version>
<configuration>
<version>3.1</version>
</configuration>
</plugin>
</plugins>
<finalName>webserver</finalName>
</build>