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Spring Boot 是 Spring 框架的简化版本,专为快速构建微服务应用而设计。它结合了传统的 Spring 应用程序开发与现代应用需求,提供了一套完整的工具链,涵盖了从开发到部署的全生命周期。
Spring 是一个功能全面的应用开发框架,包含以下主要组成部分:
Spring Boot 不是一个全新的框架,而是基于 Spring 的基础功能进行了封装和简化。其主要特点包括:
现代 Java 开发趋势:
Java 环境安装
IDE安装
Maven配置
Spring CLI 是一个命令行工具,可以快速创建和运行Spring Boot应用。常用命令包括:
mvn spring:run:运行主类mvn clean install:构建项目mvn spring-boot:run:通过Maven运行应用Spring Initializr 是一个在线工具,用于快速创建Spring Boot项目:
Spring Boot 的自动配置机制是其最具亮点之一。核心原理如下:
spring.jpa.hibernate.ddl-auto = updatespring.datasource.url = jdbc:mysql://localhost:3306/mydb
@Import({@AutoConfigureClasspath}) @SpringBootApplicationpublic class MyApplication { public static void main(String[] args) { SpringApplication.run(MyApplication.class, args); }} @SpringBootApplication:标记主类@RestController:标记控制器类@RequestMapping:定义API映射路径@GetMapping:定义GET请求映射@PostMapping:定义POST请求映射@PutMapping:定义PUT请求映射@DeleteMapping:定义DELETE请求映射@Service:标记业务逻辑类@Component:标记组件类Spring Boot 提供了两种主要的ORM工具:
MyBatis
JPA
Spring Boot 提供了几种模板引擎:
.ftl为扩展名.html为扩展名.mustache为扩展名.groovy为扩展名Spring Boot 提供了多种缓存实现:
@RedisCache(cacheNames = "myCache")class MyService { @Autowired private RedisTemplate redisTemplate; public void cacheMethod() { redisTemplate.opsForValue().set("key", "value"); }} @Cacheable(cacheNames = "myMapCache")public MapcacheMap() { // 具体实现}
在分布式系统中,Session管理是关键。Spring Boot 提供了两种方案:
@EnableRedisSessionclass MySessionConfig { @Autowired private RedisSerializer redisSerializer; @Bean public RedisSessionDecorator redisSessionDecorator() { return new RedisSessionDecorator(redisSerializer); }} @EnableMongoDBSessionclass MySessionConfig { @Autowired private MongoSessionOptions mongoSessionOptions; @Bean public SessionFactory sessions() { return new MongoSessionFactory(); }} Spring Boot 提供了任务调度功能,主要通过 Quartz Scheduler 实现:
import org.springframework.scheduling.annotation.EnableScheduling;import org.springframework.scheduling.annotation.IntervalAnnotation;import org.springframework.scheduling.annotation.ScheduledAnnotation;@EnableSchedulingclass MyScheduler { @Scheduled(enabled = true, fixedRate = true, initialDelay = 10) public void scheduledTask() { // 定期执行的任务逻辑 }} Spring Batch 是Spring Boot提供的批量处理框架,主要功能包括:
import org.springframework.batch.core.Job;import org.springframework.batch.core.Step;import org.springframework.batch.core.configuration.JobBuilderFactory;import org.springframework.batch.core.configuration.StepBuilderFactory;public class MyBatchConfig { @Autowired private JobBuilderFactory jobBuilderFactory; @Autowired private StepBuilderFactory stepBuilderFactory; @Bean public Job myBatchJob() { return jobBuilderFactory.get("myBatchJob") .listener(new JobExecutionListener()) .withStepBuilderFactory(stepBuilderFactory.get("myStep")) .build(); } @Bean public Step myBatchStep() { return stepBuilderFactory.get("myStep") .taskExecutor() .listener(new StepExecutionListener()) .build(); }} Spring Boot 提供了简单的邮件发送功能,主要通过 JavaMail Sender 实现:
import org.springframework.mail.javamail.JavaMailSender;import org.springframework.mail.javamail.MimeMessage;public class MyMailService { @Autowired private JavaMailSender mailSender; public void sendMail(String to, String subject, String content) { try { MimeMessage message = new MimeMessage(); message.setFrom("spring@domain.com"); message.setTo(to); message.setSubject(subject); message.setText(content); mailSender.send(message); } catch (Exception e) { // 处理邮件发送异常 } }} Spring Boot 支持多种消息队列:
import org.springframework.boot.autoconfigure.kafka.KafkaProperties;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class KafkaConfig { @Autowired private KafkaProperties kafkaProperties; @Bean public KafkaProducer kafkaProducer() { return new KafkaProducer<>(kafkaProperties.toString(), kafkaProperties.toString()); }} import com.rabbitmq.client.Connection;import org.springframework.amqp.rabbit.core.RabbitTemplate;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class RabbitMqConfig { @Autowired private RabbitTemplate rabbitTemplate; @Bean public Connection createRabbitMqConnection() throws IOException { // 连接RabbitMQ服务器 }} import org.apache.activemq.ActiveMQConnectionFactory;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class ActiveMqConfig { @Autowired private ActiveMQConnectionFactory activeMQConnectionFactory; @Bean public Connection createActiveMqConnection() throws IOException { // 连接ActiveMQ服务器 }} Spring Boot 提供了几种序列化工具:
import com.google.gson.Gson;@Autowiredprivate Gson gson;
import com.alibaba.fastjson.JSON;@Autowiredprivate JSON json;
Spring Boot 与分布式框架的集成:
import org.springframework.boot dubbo DubboAutoConfiguration;import org.springframework.boot dubbo DubboProperties;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class DubboConfig { @Autowired private DubboProperties dubboProperties; @Bean public DubboAutoConfiguration dubboAutoConfiguration() { return new DubboAutoConfiguration(dubboProperties); }} Spring Boot 安全模块主要通过 Spring Security 和 Shiro 实现:
import org.springframework.security.config.annotation.web.builders.WebSecurity;import org.springframework.security.config.annotation.web.config.EnableWebSecurity;import org.springframework.security.web.SecurityFilterChain;@EnableWebSecuritypublic class SecurityConfig { @Autowired private WebSecurity webSecurity; @Bean public SecurityFilterChain securityFilterChain() { return webSecurity .addFilterChain("/api/**", SecurityFilterChain.basicAuthentication()) .build(); }} import org.apache.shiro.config.InMemoryConfiguration;import org.apache.shiro.spring.web.SecurityFilterChain;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class ShiroConfig { @Bean public SecurityFilterChain securityFilterChain() { return new SecurityFilterChain( new InMemoryConfiguration() .set("shiro.sessionManager.sessionIdCookie.name", "JSESSIONID") .set("shiro.sessionManager.sessionIdCookie.domain", "localhost") .addFilter("JSESSIONIDFilter") .addFilter("ShiroFilterChain") ); }} Spring Boot 提供了强大的监控和运维工具:
import org.springframework.boot.actuate.autoconfigure.EnableActuator;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configuration@EnableActuatorpublic class ActuatorConfig { @Bean public HealthContributor healthContributor() { return new HealthContributor(); }} import org.springframework.boot.devtools.autoconfigure.DevToolsAutoConfiguration;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class DevToolsConfig { @Bean public DevToolsAutoConfiguration devToolsAutoConfiguration() { return new DevToolsAutoConfiguration(); }} Spring Boot 提供了 Sentinel 来实现熔断限流:
import com.alibaba.sentininel.Sentinel;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class SentinelConfig { @Bean public Sentinel sentinel() { return new Sentinel(); }} Spring Boot 提供了完善的测试框架,包括:
import org.junit.jupiter.api.Test;import org.springframework.boot.test.context.SpringBootTest;@SpringBootTestpublic class MyTest { @Test public void test() { // 测试逻辑 }} import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.test.web.client.RestTemplate;@Autowiredprivate RestTemplate restTemplate;@Testpublic void testRestTemplate() { // 调用REST API} Lombok 提供了一系列简化Java代码的注解,常用注解包括:
@Getter 和 @Setter:简化字段的获取和设置@NoArgsConstructor:生成无参数构造器@ToString:生成对象 toString 方法@EqualsAndHashCode:简化 equals 和 hashCode 方法@Slf4j:记录日志Kotlin 是一个简洁的编程语言,结合Spring Boot开发可以进一步简化代码:
import org.springframework.boot.SpringApplicationimport org.springframework.boot.autoconfigure.SpringBootApplication@SpringBootApplicationclass Application { companion object { @JvmField val application = SpringApplication() } fun main(args: Array , vararg params: String) { application.run(*params) }}class MyService { @Autowired private lateinit var repository: MyRepository fun saveEntity(entity: MyEntity) { repository.save(entity) }} 在分布式系统中,分布式锁可以通过Redis实现:
import org.springframework.beans.factory.annotation.Autowired;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class RedisLockConfig { @Autowired private RedisLockTemplate redisLockTemplate; @Bean public RedisLockTemplate redisLockTemplate() { return new RedisLockTemplate(); }}class MyService { @Autowired private RedisLockTemplate redisLockTemplate; public String acquireLock() { return redisLockTemplate.acquireLock("myLock"); }} Spring Boot 可以与Elasticsearch(ES)集成,实现文档存储和搜索:
import org.elasticsearch.client.RestClient;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class EsConfig { @Autowired private RestClient restClient; @Bean public EsConfig esConfig() { return new EsConfig(restClient); }}class EsService { @Autowired private ElasticsearchTemplate elasticsearchTemplate; public void saveDocument(Map document) { elasticsearchTemplate.index("my-index", "my-type", document); } public List Spring Reactive 提供了基于Reactive Streams的异步编程支持:
import org.springframework.boot.web.reactive.config.EnableWebFlux;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configuration@EnableWebFluxpublic class WebFluxConfig { @Bean public RouterFunction home() { return RouterFunctions.route( GetMapping("/hello") .toPath("/home", homeHandler()) ); } @Bean public HandlerFunction homeHandler() { return response -> response.json().body("Hello, Spring Boot WebFlux"); }} Spring Boot支持RxJava和RxKotlin实现异步处理:
import io.reactivex.rxjava.schedulers.Schedulersimport org.springframework.boot.web.reactive.config.EnableWebFluximport org.springframework.context.annotation.Beanimport org.springframework.context.annotation.Configuration@Configuration@EnableWebFluxpublic class WebFluxConfig { @Bean public RouterFunction home() { return RouterFunctions.route( GetMapping("/hello") .toPath("/home", homeHandler()) ) } @Bean public HandlerFunction homeHandler() { return response -> response.json().body("Hello, Spring Boot WebFlux") }} Spring Boot 提供了OAuth2客户端支持,主要通过 Spring Security 实现:
import org.springframework.security.oauth2.client.OAuth2Client;import org.springframework.security.oauth2.client.OAuth2ClientConfigurer;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configurationpublic class OAuth2Config { @Bean public OAuth2Client oauth2Client() { return new OAuth2ClientConfigurer() .withClientId("client-id") .withClientSecret("client-secret") .withTokenName("access_token") .withAuthorizationUri("http://localhost:8080/auth") .withRedirectUri("http://localhost:8081/callback") .build(); }} Spring Boot可以与Neo4j图数据库集成:
import org.springframework.data.neo4j.repository.config.EnableNeo4jRepositories;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;@Configuration@EnableNeo4jRepositories(basePackages = "com.example.graph")public class Neo4jConfig { @Bean public Neo4jServer neo4jServer() { return new Neo4jServer("localhost", 7474); }} Spring Boot支持通过 Spring Data Commons 实现函数式编程:
import org.springframework.data.domain ReyesQuery;import org.springframework.data.domain.commons.Query;import org.springframework.data.domain.commons.Specification;import org.springframework.data.repository.Repository;@Repositoryinterface MyRepository : Repository{ @Query("select e.name from MyEntity e where e.age : age") ReyesQuery queryAge(@QueryParameters Long age);}class MyService { @Autowired private MyRepository myRepository; public List findByAge(Long age) { return myRepository.queryAge(age); }}
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