Java 没有父pom.xml的spring-boot无法生成war包

spring-boot without parent pom.xml cannot generate war packaging

提问by Matthias Brenner

I used the example gs-convert-jar-to-war provided by spring-io. It describes how to generate war packaging within a spring boot project.

我使用了 spring-io 提供的示例 gs-convert-jar-to-war。它描述了如何在 Spring Boot 项目中生成 war 包。

The spring-boot documentation allows for using own parent poms, thus omitting the predefined parent pom for all spring-boot projects. The following dependency has to be added:

spring-boot 文档允许使用自己的父 pom，因此省略了所有 spring-boot 项目的预定义父 pom。必须添加以下依赖项：

<dependencyManagement>
    <dependencies>
        <dependency>
            <!-- Import dependency management from Spring Boot -->
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>1.0.1.RELEASE</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

I applied this change (and only this change) to the example. Afterwards it is no longer possible to generate the war. I get following error message:

我将此更改（并且仅此更改）应用于示例。之后就不可能再产生战争了。我收到以下错误消息：

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-war-plugin:2.1.1:war (default-war) on project gs-convert-jar-to-war: Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in update mode) -> [Help 1]

Here is the complete listing of the modified pom.xml:

这是修改后的 pom.xml 的完整列表：

<?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>org.springframework-sample</groupId>
    <artifactId>gs-convert-jar-to-war</artifactId>
    <version>0.1.0</version>
    <packaging>war</packaging>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <!-- Import dependency management from Spring Boot -->
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-parent</artifactId>
                <version>1.0.1.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
            </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
            </dependency>
    </dependencies>

    <properties>
        <start-class>hello.Application</start-class>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>http://repo.spring.io/libs-milestone</url>
        </repository>
    </repositories>

    <pluginRepositories>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>http://repo.spring.io/libs-milestone</url>
        </pluginRepository>
    </pluginRepositories>

</project>

Is there any idea to overcome the problem?

有什么想法可以克服这个问题吗？

In my project I will use my own parent pom, because it defines a lot of stuff regarding the company.

在我的项目中，我将使用我自己的父 pom，因为它定义了很多关于公司的东西。

采纳答案by Dave Syer

You removed the parent, so you lost its declaration of the WAR plugin configuration. Here it is:

您删除了父级，因此您丢失了它对 WAR 插件配置的声明。这里是：

<plugin>
    <artifactId>maven-war-plugin</artifactId>
    <configuration>
        <failOnMissingWebXml>false</failOnMissingWebXml>
    </configuration>
</plugin>

See herefor the source code.

请参阅此处获取源代码。

N.B. this is not necessary with Spring Boot 2.0 parent pom and above (the war plugin version is different), or if you use the latest war plugin.

注意，对于 Spring Boot 2.0 父 pom 及更高版本（war 插件版本不同），或者如果您使用最新的 war 插件，这不是必需的。