Maven打包项目失败；报错：Failed to execute goal org.apache.maven.plugins:maven-war-plugin:2.1.1:war (default-war) on project Hello: Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/we

报错信息：

E:\MIKEY\mikey\HTML5\TestMaven_01>mvn package
[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building TestMaven_01 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-resources-plugin:2.5:resources (default-resources) @ Hello ---
[debug] execute contextualize
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] skip non existing resourceDirectory E:\MIKEY\mikey\HTML5\TestMaven_01\src\main\resources
[INFO]
[INFO] --- maven-compiler-plugin:2.3.2:compile (default-compile) @ Hello ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] --- maven-resources-plugin:2.5:testResources (default-testResources) @ Hello ---
[debug] execute contextualize
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 0 resource
[INFO]
[INFO] --- maven-compiler-plugin:2.3.2:testCompile (default-testCompile) @ Hello ---
[INFO] Nothing to compile - all classes are up to date
[INFO]
[INFO] --- maven-surefire-plugin:2.10:test (default-test) @ Hello ---
[INFO] Surefire report directory: E:\MIKEY\mikey\HTML5\TestMaven_01\target\surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.mikey.www.maven.HelloTest
hello
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.061 sec

Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

[INFO]
[INFO] --- maven-war-plugin:2.1.1:war (default-war) @ Hello ---
[INFO] Packaging webapp
[INFO] Assembling webapp [Hello] in [E:\MIKEY\mikey\HTML5\TestMaven_01\target\Hello-0.0.1-SNAPSHOT]
[INFO] Processing war project
[INFO] Webapp assembled in [158 msecs]
[INFO] Building war: E:\MIKEY\mikey\HTML5\TestMaven_01\target\Hello-0.0.1-SNAPSHOT.war
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.280s
[INFO] Finished at: Mon Aug 20 07:24:53 CST 2018
[INFO] Final Memory: 8M/155M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-war-plugin:2.1.1:war (default-war) on project Hello: Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in update mode) -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
E:\MIKEY\mikey\HTML5\TestMaven_01>

报错原因：

原因:找不到web.xml,但是项目中明明有这个文件,在WebContent/WEB-INF/文件夹下,就是识别不了

解决方法：

需要在pom.xml文件中,加上maven-war-plugin插件配置
在<build>节点中增加:

    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-war-plugin</artifactId>
            <version>2.4</version>
            <configuration>
                <webResources>
                    <resource>
                        <directory>WebContent</directory>
                    </resource>
                </webResources>
            </configuration>
        </plugin>
    </plugins>

如果项目中原本没有web.xml文件,就需要加上下面的配置:

<build>
      <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-war-plugin</artifactId>
            <version>2.4</version>
            <configuration>
                <failOnMissingWebXml>false</failOnMissingWebXml>
            </configuration>
        </plugin>
    </plugins>
  </build>

结果：