Spring Boot开启的 2 种方式

Spring Boot依赖

使用Spring Boot很简单，先添加基础依赖包，有以下两种方式

1. 继承spring-boot-starter-parent项目

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.6.RELEASE</version>
</parent>

2. 导入spring-boot-dependencies项目依赖

<dependencyManagement>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-dependencies</artifactId>
			<version>1.5.6.RELEASE</version>
			<type>pom</type>
			<scope>import</scope>
		</dependency>
</dependencyManagement>

Spring Boot依赖注意点

1. 属性覆盖只对继承有效

This only works if your Maven project inherits (directly or indirectly) from spring-boot-dependencies. If you have added spring-boot-dependencies in your own dependencyManagement section with import you have to redefine the artifact yourself instead of overriding the property.

Spring Boot依赖包里面的组件的版本都是和当前Spring Boot绑定的，如果要修改里面组件的版本，只需要添加如下属性覆盖即可，但这种方式只对继承有效，导入的方式无效。

<properties>
    <slf4j.version>1.7.25<slf4j.version>
</properties>

如果导入的方式要实现版本的升级，达到上面的效果，这样也可以做到，把要升级的组件依赖放到Spring Boot之前。

<dependencyManagement>
    <dependencies>
        <!-- Override Spring Data release train provided by Spring Boot -->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-releasetrain</artifactId>
            <version>Fowler-SR2</version>
            <scope>import</scope>
            <type>pom</type>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>1.5.6.RELEASE</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

Each Spring Boot release is designed and tested against a specific set of third-party dependencies. Overriding versions may cause compatibility issues.

需要注意，要修改Spring Boot的依赖组件版本可能会造成不兼容的问题。