如何在Spring Boot中將所有通用依賴項從Maven模塊移至父模塊

Question

我有兩個簡單的Spring Boot應用程序，一個是eureka-server ，另一個是eureka-client 。 它們都駐留在Maven聚合器模塊eureka-sample 。

我希望在eureka-server和eureka-client應用程序中都有一些共同的依賴關系，因此我希望移至父pom，這樣就不必時不時地將它們包含在每個子模塊中。

我嘗試將依賴項spring-boot-starter-test從子模塊移到<dependencyManagement>部分下的父pom中，但是由於這些類無法找到jar ，因此子模塊中的測試無法編譯。 可能是我配置錯誤或放置在錯誤的部分。

我該如何實現？

尤里卡樣本（父pom.xml）

<?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.study.spring</groupId>
    <artifactId>eureka-sample</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>
    <name>eureka-sample</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Dalston.SR4</spring-cloud.version>
    </properties>

    <modules>
        <module>eureka-server</module>
        <module>eureka-client</module>
    </modules>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.8.RELEASE</version>
        <relativePath />
    </parent>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

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

</project>

eureka-server / pom.xml

<?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>
    <artifactId>eureka-server</artifactId>
    <packaging>jar</packaging>
    <name>eureka-server</name>
    <description>Demo project for Spring Boot</description>
    <parent>
        <groupId>com.study.spring</groupId>
        <artifactId>eureka-sample</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka-server</artifactId>
        </dependency>

        **<!-- ALL THE FOLLOWING 3 DEPENDENCIES SHOULD GO TO PARENT POM SO THAT I DO NOT HAVE TO PUT THEM IN EVERY CHILD MODULE -->**
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

eureka-client / pom.xml

<?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>
    <artifactId>eureka-client</artifactId>
    <packaging>jar</packaging>
    <name>eureka-client</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>com.study.spring</groupId>
        <artifactId>eureka-sample</artifactId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka</artifactId>
        </dependency>

        **<!-- ALL THE FOLLOWING 3 DEPENDENCIES SHOULD GO TO PARENT POM SO THAT I DO NOT HAVE TO PUT THEM IN EVERY CHILD MODULE -->**
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

</project>

Answer 1

嘗試將公共依賴項放在父.pom的<dependencies>部分中，而不是在<dependencyManagement>部分中。

使用<dependencyManagement>您只需要准備和配置所有子模塊的依賴關系，但是為了實際使用它們，您仍然需要從子模塊中引用它們。

差異是細微的，但很重要-有關詳細信息，請參見https://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html 。