Spring Boot Starter 簡介
Spring Boot Starter
是一組方便使用的依賴關係描述符,可以在應用程序中包含這些描述符。藉助Spring Boot Starter
開發人員可以獲得所需的所有 Spring 及相關技術的一站式服務,而無需查看示例代碼或複製粘貼依賴的庫文件。譬如,如果需要 Spring JPA 訪問數據庫,則可以在工程中直接飲用spring-boot-starter-data-jpa
- 有關
starter
命名規範,所有官方發佈的starter
都遵循以下命名模式spring-boot-starter-*
,其中*
指特定的應用程序代號或名稱。任何第三方提供的starter
都不能以spring-boot
作爲前綴,應該將應用程序代號或名稱作爲前綴,譬如mybatis-spring-boot-starter
Spring Boot Starter 開發步驟
本次以 redisson
爲例,開發自己的 starter
,命名爲redisson-spring-boot-starter
第一步 新建 maven 工程 redisson-spring-boot-starter
相信各位小夥都非常熟練,不多說了,省略
第二步 添加 pom 依賴,完整 pom.xml
文件如下
<?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.lushwe</groupId>
<artifactId>redisson-spring-boot-starter</artifactId>
<version>1.0</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<java.version>1.8</java.version>
<spring.boot.version>2.0.4.RELEASE</spring.boot.version>
<redisson.version>3.4.4</redisson.version>
</properties>
<dependencies>
<!-- spring boot autoconfigure 依賴 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-autoconfigure</artifactId>
<version>${spring.boot.version}</version>
<scope>compile</scope>
<optional>true</optional>
</dependency>
<!-- redisson 依賴 -->
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson</artifactId>
<version>${redisson.version}</version>
<scope>compile</scope>
<optional>true</optional>
</dependency>
</dependencies>
</project>
備註:
<optional>true</optional>
表示當前依賴包是可選
的,也就是說,我們引入redisson-spring-boot-starter
默認不會引入redisson
依賴,好處就是,我們可以先引入redisson-spring-boot-starter
, 然後在需要用到redisson
功能時再引入redisson
包
第二步 新建 redisson 的配置屬性類,完整 RedissonProperties
類如下
package org.redisson.spring.boot.autoconfigure;
import org.springframework.boot.context.properties.ConfigurationProperties;
/**
* 說明:Redisson的配置屬性
*
* @author Jack Liu
* @date 2019-06-13 15:31
* @since 1.0
*/
@ConfigurationProperties(prefix = RedissonProperties.MYBATIS_PREFIX)
public class RedissonProperties {
/**
* 配置文件前綴
*/
public static final String MYBATIS_PREFIX = "redisson";
/**
* 配置文件路徑
*/
private String configLocation;
public String getConfigLocation() {
return configLocation;
}
public void setConfigLocation(String configLocation) {
this.configLocation = configLocation;
}
}
備註:
@ConfigurationProperties(prefix = RedissonProperties.MYBATIS_PREFIX)
表示前綴爲redisson
的屬性纔會注入到RedissonProperties
第三步 新建 redisson 的自動配置類,完整 RedissonAutoConfiguration
類如下
package org.redisson.spring.boot.autoconfigure;
import org.redisson.Redisson;
import org.redisson.api.RedissonClient;
import org.redisson.config.Config;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;
import java.io.IOException;
/**
* 說明:Redisson自動配置
*
* @author Jack Liu
* @date 2019-06-13 15:31
* @since 1.0
*/
@Configuration
@ConditionalOnClass({RedissonClient.class})
@ConditionalOnProperty(prefix = "redisson", name = "config-location")
@EnableConfigurationProperties({RedissonProperties.class})
public class RedissonAutoConfiguration {
private final ResourceLoader resourceLoader;
private final RedissonProperties properties;
// 構造方法注入
public RedissonAutoConfiguration(RedissonProperties properties, ResourceLoader resourceLoader) {
this.properties = properties;
this.resourceLoader = resourceLoader;
}
@Bean(destroyMethod = "shutdown")
@ConditionalOnMissingBean
public RedissonClient redissonClient() throws IOException {
Resource resource = this.resourceLoader.getResource(this.properties.getConfigLocation());
Config config = null;
if (this.properties.getConfigLocation().endsWith(".yaml")) {
config = Config.fromYAML(resource.getFile());
} else if (this.properties.getConfigLocation().endsWith(".json")) {
config = Config.fromJSON(resource.getFile());
}
return config != null ? Redisson.create(config) : Redisson.create();
}
}
備註:
@ConditionalOnClass({RedissonClient.class})
表示classpath
下有RedissonClient
類纔會啓用RedissonAutoConfiguration
。也就是說,沒有引入redisson
依賴包,RedissonAutoConfiguration
不會生效@ConditionalOnProperty(prefix = "redisson", name = "config-location")
表示配置文件有redisson.config-location
屬性, 纔會啓用RedissonAutoConfiguration
。
第四步 創建配置,新建 redisson 的自動配置類,完整 RedissonAutoConfiguration
類如下
resource
目錄下,創建META-INF
目錄META-INF
目錄下創建spring.factories
文件
# Auto Configure
org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
org.redisson.spring.boot.autoconfigure.RedissonAutoConfiguration
META-INF
目錄下創建spring.provides
文件
provides: redisson-spring-boot-starter
第五步 至此,redisson starter 開發完成,打包結束
Spring Boot Starter 使用
resisson-spring-boot-starter
已經開發完成,下面演示如何使用我們自己開發的 starter
- 新建一個工程,引入上面開發好的
resisson-spring-boot-starter
,完整pom.xml
如下
<?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">
<parent>
<artifactId>learn-spring-boot</artifactId>
<groupId>com.lushwe.learn</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>spring-boot-starter-test</artifactId>
<properties>
<spring.boot.version>2.0.4.RELEASE</spring.boot.version>
<redisson.version>3.4.4</redisson.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<version>${spring.boot.version}</version>
</dependency>
<dependency>
<groupId>com.lushwe</groupId>
<artifactId>redisson-spring-boot-starter</artifactId>
<version>1.0</version>
</dependency>
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson</artifactId>
<version>${redisson.version}</version>
</dependency>
</dependencies>
</project>
- 創建
application.properties
文件,配置redisson.config-location
,詳細如下
# Redisson 配置
redisson.config-location=classpath:redisson-redis.yaml
- 創建
redisson-redis.yaml
文件,詳細如下
masterSlaveServersConfig:
slaveAddresses:
- "redis://10.0.10.23:15489"
masterAddress: "redis://10.0.10.23:15389"
password: codis*23
idleConnectionTimeout: 10000
pingTimeout: 1000
connectTimeout: 10000
timeout: 3000
retryAttempts: 3
retryInterval: 1500
reconnectionTimeout: 3000
failedAttempts: 3
subscriptionsPerConnection: 5
clientName: null
loadBalancer: !<org.redisson.connection.balancer.RoundRobinLoadBalancer> {}
slaveSubscriptionConnectionMinimumIdleSize: 1
slaveSubscriptionConnectionPoolSize: 50
slaveConnectionMinimumIdleSize: 10
slaveConnectionPoolSize: 64
masterConnectionMinimumIdleSize: 10
masterConnectionPoolSize: 64
readMode: "SLAVE"
threads: 0
nettyThreads: 0
codec: !<org.redisson.codec.JsonJacksonCodec> {}
useLinuxNativeEpoll: false
- 創建一個啓動類
Application
,詳細如下
package com.lushwe.spring.boot.start.test;
import org.redisson.api.RBucket;
import org.redisson.api.RedissonClient;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
/**
* 說明:應用啓動類
*
* @author Jack Liu
* @date 2019-06-12 13:28
* @since 1.0
*/
@SpringBootApplication
public class Application {
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(Application.class, args);
System.out.println(context.getBean("redissonClient"));
RedissonClient redissonClient = context.getBean(RedissonClient.class);
System.out.println(redissonClient);
RBucket<String> bucket1 = redissonClient.getBucket("redisson-v");
bucket1.set("lushwe1");
System.out.println(bucket1.get());
RBucket<String> bucket2 = redissonClient.getBucket("redisson-v");
bucket2.set("lushwe2");
System.out.println(bucket2.get());
RBucket<String> bucket3 = redissonClient.getBucket("redisson-v");
System.out.println(bucket3.get());
}
}
運行 Application
,日誌打印如下
日誌顯示,我們能正常使用 RedissonClient
了
本文主要介紹瞭如何開發你自己的 starter
,以及如何使用 starter
,比較簡單,如有什麼問題歡迎指正和提問。
本文完