java - 模块所需的 Maven 项目配置不可用

Question

我有一个在 Tomcat 8 服务器上运行的 Java/Maven/JSP。项目结构如下，

我在下面提供了这个 pom.xml 文件，

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>com.puut.wallet</groupId>
    <version>1.0-SNAPSHOT</version>
    <packaging>war</packaging>
    <artifactId>WalletApp</artifactId>
    <name>simple-bitcoin-wallet</name>

    <parent>
        <groupId>org.bitcoinj</groupId>
        <artifactId>bitcoinj-parent</artifactId>
        <version>RELEASE</version>
    </parent>

    <build>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
            <resource>
                <directory>src/main/java</directory>
            </resource>
        </resources>
    </build>

    <dependencies>
        <dependency>
            <groupId>org.bitcoinj</groupId>
            <artifactId>bitcoinj-core</artifactId>
            <version>${project.parent.version}</version>
        </dependency>
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>18.0</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.20</version>
        </dependency>
        <dependency>
            <groupId>net.glxn</groupId>
            <artifactId>qrgen</artifactId>
            <version>1.3</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>3.1.0</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

当我运行项目时，出现以下错误，

Error:Maven Resources Compiler: Maven project configuration required for module 'WalletApp' isn't available. Compilation of Maven projects is supported only if external build is started from an IDE.

我采取了一些措施，

a. in the terminal, run `mvn clean`
b. project -> right click -> `Make Module WalletApp`
c. project -> right click -> `Recompile Module WalletApp`
d. File -> Invalide Caches/Restart .... [This restarts the project]
e. Synchronize 

显然，他们都没有解决问题。顺便说一下，我在项目中使用 InteliIJ。我应该怎么做才能解决这个问题？

Answer 1

在 Event Log 中，我可以选择Add as maven project。我选择了那个选项，问题立即得到解决。