【Spring Boot】自定义starter

为什么要自定义Starter

Spring Boot Starter 是一种简化依赖管理和自动配置的机制。下面详细介绍如何创建自定义 Starter。

Starter 的基本概念

命名规范

官方 Starter: spring-boot-starter-{name}
自定义 Starter: {name}-spring-boot-starter

核心组件

autoconfigure 模块: 包含自动配置逻辑

starter 模块: 只包含依赖管理

创建自定义 Starter

项目结构

my-starter/
├── my-spring-boot-autoconfigure/
│   ├── src/main/java/
│   │   └── com/example/mystarter/
│   └── pom.xml
└── my-spring-boot-starter/├── src/main/resources/│   └── META-INF/│       └── spring.factories└── pom.xml

自动配置模块

<!-- my-spring-boot-autoconfigure/pom.xml -->
<dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-autoconfigure</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-configuration-processor</artifactId><optional>true</optional></dependency>
</dependencies>

配置属性类

@ConfigurationProperties(prefix = "my.service")
public class MyServiceProperties {private String prefix = "Hello";private String suffix = "!";// getters and setterspublic String getPrefix() { return prefix; }public void setPrefix(String prefix) { this.prefix = prefix; }public String getSuffix() { return suffix; }public void setSuffix(String suffix) { this.suffix = suffix; }
}

服务类

public class MyService {private final String prefix;private final String suffix;public MyService(String prefix, String suffix) {this.prefix = prefix;this.suffix = suffix;}public String wrap(String message) {return prefix + " " + message + " " + suffix;}
}

自动配置类

@Configuration
@ConditionalOnClass(MyService.class)
@EnableConfigurationProperties(MyServiceProperties.class)
public class MyServiceAutoConfiguration {@Bean@ConditionalOnMissingBeanpublic MyService myService(MyServiceProperties properties) {return new MyService(properties.getPrefix(), properties.getSuffix());}@Bean@ConditionalOnProperty(name = "my.service.enabled", havingValue = "true")@ConditionalOnMissingBeanpublic MyServiceController myServiceController(MyService myService) {return new MyServiceController(myService);}
}

注册自动配置

在 src/main/resources/META-INF/spring.factories 中：

org.springframework.boot.autoconfigure.EnableAutoConfiguration=com.example.mystarter.MyServiceAutoConfiguration

需要注意，spring boot 3.x 取消了spring.factories, 替代方案为在路径 src/main/resources/META-INF/spring 创建一个文件org.springframework.boot.autoconfigure.AutoConfiguration.imports

把需要自动装配一行一行放入

com.example.mystarter.MyServiceAutoConfiguration