【maven 报错】maven项目执行maven install时报错Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in update mode)

在使用maven新建的web项目中，执行

执行如上的这两个操作，报错：

 [ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.5.1:compile (default-compile) on project bioligyInfo: Fatal error compiling: tools.jar not found: C:\Program Files\Java\jre1.8.0_73\..\lib\tools.jar -> [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

 [ERROR] Failed to execute goal org.apache.maven.plugins:maven-war-plugin:2.2:war (default-war) on project bioligyInfo: 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

上面的两种错误，提示的很明显：

错误1：

其实不用从maven下载插件，只需要保证你的pom.xml文件中有如下的信息即可：

  <build>
       <plugins>
           <plugin>
               <artifactId>maven-war-plugin</artifactId>
               <configuration>
                   <version>2.5</version>
               </configuration>
           </plugin>
       </plugins>
   </build>

   <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <spring.version>4.1.4.RELEASE</spring.version>
        <hibernate.version>4.3.8.Final</hibernate.version>
        <jackson.version>2.5.0</jackson.version>                                                            

    </properties>  

错误2：

提示找不到web.xml文件

解决方法：

1》如果你没有配置web.xml文件，那就创建web.xml文件

2》如果你配置了web.xml文件，还有这样的错误，那就是你的web.xml文件不能被你项目读取到

如下，项目中web.xml的位置如下：

而我们需要让项目读取到它：

因为web.xml文件的路径如下：src\main\webapp\WEB-INF\web.xml

如果依旧无法解决，那就在pom.xml文件中配置如下：

   <build>
       <plugins>
           <plugin>
               <artifactId>maven-war-plugin</artifactId>
               <configuration>
                   <version>2.5</version>
               <webXml>src\main\webapp\WEB-INF\web.xml</webXml>
               </configuration>
           </plugin>
       </plugins>
   </build>

这样指定到具体的文件上  就可以解决这问题了。