SpringBoot使用手册

SpringBoot使用手册

1、自动装配

1.1、创建spring Boot项目

在之前的文章中已经专门写过，这里不做赘述。

1.2、pom.xml

1.2.1、版本管理

在学习完maven项目后，我们学习框架时首先阅读的就是pom.xml文件，这里是管理自己该项目中所用到的jar包。

学习SpringBoot时也是一样，在创建好一个项目后，我们首先先浏览一下pom.xml。

<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.7.3</version><relativePath/> <!-- lookup parent from repository --></parent>

打开这个文件后，我们首先就能看到上面这串代码，这个和我们之前学习的不太一样，仔细阅读后可以发现，这时导入Springboot父依赖的代码。

什么是父依赖？

当我们按住ctrl，鼠标点击这个依赖，可以发现我们又进入了一个pom文件，在这里，我们又能看到一个父依赖。

<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-dependencies</artifactId><version>2.7.3</version></parent>

再次点击进入，便能发现这里管理着大量的版本信息：

<properties><activemq.version>5.16.5</activemq.version><antlr2.version>2.7.7</antlr2.version><appengine-sdk.version>1.9.98</appengine-sdk.version><artemis.version>2.19.1</artemis.version><aspectj.version>1.9.7</aspectj.version><assertj.version>3.22.0</assertj.version><atomikos.version>4.0.6</atomikos.version><awaitility.version>4.2.0</awaitility.version><build-helper-maven-plugin.version>3.3.0</build-helper-maven-plugin.version><byte-buddy.version>1.12.13</byte-buddy.version><cache2k.version>2.6.1.Final</cache2k.version><caffeine.version>2.9.3</caffeine.version><cassandra-driver.version>4.14.1</cassandra-driver.version><classmate.version>1.5.1</classmate.version><commons-codec.version>1.15</commons-codec.version><commons-dbcp2.version>2.9.0</commons-dbcp2.version><commons-lang3.version>3.12.0</commons-lang3.version><commons-pool.version>1.6</commons-pool.version><commons-pool2.version>2.11.1</commons-pool2.version><couchbase-client.version>3.3.3</couchbase-client.version><db2-jdbc.version>11.5.7.0</db2-jdbc.version><dependency-management-plugin.version>1.0.13.RELEASE</dependency-management-plugin.version><derby.version>10.14.2.0</derby.version><dropwizard-metrics.version>4.2.11</dropwizard-metrics.version><ehcache.version>2.10.9.2</ehcache.version><ehcache3.version>3.10.0</ehcache3.version><elasticsearch.version>7.17.4</elasticsearch.version><embedded-mongo.version>3.4.8</embedded-mongo.version><flyway.version>8.5.13</flyway.version><freemarker.version>2.3.31</freemarker.version><git-commit-id-plugin.version>4.9.10</git-commit-id-plugin.version><glassfish-el.version>3.0.4</glassfish-el.version><glassfish-jaxb.version>2.3.6</glassfish-jaxb.version><glassfish-jstl.version>1.2.6</glassfish-jstl.version><graphql-java.version>18.3</graphql-java.version><groovy.version>3.0.12</groovy.version><gson.version>2.9.1</gson.version><h2.version>2.1.214</h2.version><hamcrest.version>2.2</hamcrest.version><hazelcast.version>5.1.3</hazelcast.version><hazelcast-hibernate5.version>2.2.1</hazelcast-hibernate5.version><hibernate.version>5.6.10.Final</hibernate.version><hibernate-validator.version>6.2.4.Final</hibernate-validator.version><hikaricp.version>4.0.3</hikaricp.version><hsqldb.version>2.5.2</hsqldb.version><htmlunit.version>2.60.0</htmlunit.version><httpasyncclient.version>4.1.5</httpasyncclient.version><httpclient.version>4.5.13</httpclient.version><httpclient5.version>5.1.3</httpclient5.version><httpcore.version>4.4.15</httpcore.version><httpcore5.version>5.1.4</httpcore5.version><infinispan.version>13.0.10.Final</infinispan.version><influxdb-java.version>2.22</influxdb-java.version><jackson-bom.version>2.13.3</jackson-bom.version><jakarta-activation.version>1.2.2</jakarta-activation.version><jakarta-annotation.version>1.3.5</jakarta-annotation.version><jakarta-jms.version>2.0.3</jakarta-jms.version><jakarta-json.version>1.1.6</jakarta-json.version><jakarta-json-bind.version>1.0.2</jakarta-json-bind.version><jakarta-mail.version>1.6.7</jakarta-mail.version><jakarta-management.version>1.1.4</jakarta-management.version><jakarta-persistence.version>2.2.3</jakarta-persistence.version><jakarta-servlet.version>4.0.4</jakarta-servlet.version><jakarta-servlet-jsp-jstl.version>1.2.7</jakarta-servlet-jsp-jstl.version><jakarta-transaction.version>1.3.3</jakarta-transaction.version><jakarta-validation.version>2.0.2</jakarta-validation.version><jakarta-websocket.version>1.1.2</jakarta-websocket.version><jakarta-ws-rs.version>2.1.6</jakarta-ws-rs.version><jakarta-xml-bind.version>2.3.3</jakarta-xml-bind.version><jakarta-xml-soap.version>1.4.2</jakarta-xml-soap.version><jakarta-xml-ws.version>2.3.3</jakarta-xml-ws.version><janino.version>3.1.7</janino.version><javax-activation.version>1.2.0</javax-activation.version><javax-annotation.version>1.3.2</javax-annotation.version><javax-cache.version>1.1.1</javax-cache.version><javax-jaxb.version>2.3.1</javax-jaxb.version><javax-jaxws.version>2.3.1</javax-jaxws.version><javax-jms.version>2.0.1</javax-jms.version><javax-json.version>1.1.4</javax-json.version><javax-jsonb.version>1.0</javax-jsonb.version><javax-mail.version>1.6.2</javax-mail.version><javax-money.version>1.1</javax-money.version><javax-persistence.version>2.2</javax-persistence.version><javax-transaction.version>1.3</javax-transaction.version><javax-validation.version>2.0.1.Final</javax-validation.version><javax-websocket.version>1.1</javax-websocket.version><jaxen.version>1.2.0</jaxen.version><jaybird.version>4.0.6.java8</jaybird.version><jboss-logging.version>3.4.3.Final</jboss-logging.version><jdom2.version>2.0.6.1</jdom2.version><jedis.version>3.8.0</jedis.version><jersey.version>2.35</jersey.version><jetty-el.version>9.0.52</jetty-el.version><jetty-jsp.version>2.2.0.v201112011158</jetty-jsp.version><jetty-reactive-httpclient.version>1.1.12</jetty-reactive-httpclient.version><jetty.version>9.4.48.v20220622</jetty.version><jmustache.version>1.15</jmustache.version><johnzon.version>1.2.18</johnzon.version><jolokia.version>1.7.1</jolokia.version><jooq.version>3.14.16</jooq.version><json-path.version>2.7.0</json-path.version><json-smart.version>2.4.8</json-smart.version><jsonassert.version>1.5.1</jsonassert.version><jstl.version>1.2</jstl.version><jtds.version>1.3.1</jtds.version><junit.version>4.13.2</junit.version><junit-jupiter.version>5.8.2</junit-jupiter.version><kafka.version>3.1.1</kafka.version><kotlin.version>1.6.21</kotlin.version><kotlin-coroutines.version>1.6.4</kotlin-coroutines.version><lettuce.version>6.1.9.RELEASE</lettuce.version><liquibase.version>4.9.1</liquibase.version><log4j2.version>2.17.2</log4j2.version><logback.version>1.2.11</logback.version><lombok.version>1.18.24</lombok.version><mariadb.version>3.0.7</mariadb.version><maven-antrun-plugin.version>3.0.0</maven-antrun-plugin.version><maven-assembly-plugin.version>3.3.0</maven-assembly-plugin.version><maven-clean-plugin.version>3.2.0</maven-clean-plugin.version><maven-compiler-plugin.version>3.10.1</maven-compiler-plugin.version><maven-dependency-plugin.version>3.3.0</maven-dependency-plugin.version><maven-deploy-plugin.version>2.8.2</maven-deploy-plugin.version><maven-enforcer-plugin.version>3.0.0</maven-enforcer-plugin.version><maven-failsafe-plugin.version>2.22.2</maven-failsafe-plugin.version><maven-help-plugin.version>3.2.0</maven-help-plugin.version><maven-install-plugin.version>2.5.2</maven-install-plugin.version><maven-invoker-plugin.version>3.2.2</maven-invoker-plugin.version><maven-jar-plugin.version>3.2.2</maven-jar-plugin.version><maven-javadoc-plugin.version>3.4.1</maven-javadoc-plugin.version><maven-resources-plugin.version>3.2.0</maven-resources-plugin.version><maven-shade-plugin.version>3.3.0</maven-shade-plugin.version><maven-source-plugin.version>3.2.1</maven-source-plugin.version><maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version><maven-war-plugin.version>3.3.2</maven-war-plugin.version><micrometer.version>1.9.3</micrometer.version><mockito.version>4.5.1</mockito.version><mongodb.version>4.6.1</mongodb.version><mssql-jdbc.version>10.2.1.jre8</mssql-jdbc.version><mysql.version>8.0.30</mysql.version><nekohtml.version>1.9.22</nekohtml.version><neo4j-java-driver.version>4.4.9</neo4j-java-driver.version><netty.version>4.1.79.Final</netty.version><okhttp.version>4.9.3</okhttp.version><oracle-database.version>21.5.0.0</oracle-database.version><pooled-jms.version>1.2.4</pooled-jms.version><postgresql.version>42.3.6</postgresql.version><prometheus-client.version>0.15.0</prometheus-client.version><quartz.version>2.3.2</quartz.version><querydsl.version>5.0.0</querydsl.version><r2dbc-bom.version>Borca-SR1</r2dbc-bom.version><rabbit-amqp-client.version>5.14.2</rabbit-amqp-client.version><rabbit-stream-client.version>0.5.0</rabbit-stream-client.version><reactive-streams.version>1.0.4</reactive-streams.version><reactor-bom.version>2020.0.22</reactor-bom.version><rest-assured.version>4.5.1</rest-assured.version><rsocket.version>1.1.2</rsocket.version><rxjava.version>1.3.8</rxjava.version><rxjava-adapter.version>1.2.1</rxjava-adapter.version><rxjava2.version>2.2.21</rxjava2.version><saaj-impl.version>1.5.3</saaj-impl.version><selenium.version>4.1.4</selenium.version><selenium-htmlunit.version>3.61.0</selenium-htmlunit.version><sendgrid.version>4.9.3</sendgrid.version><servlet-api.version>4.0.1</servlet-api.version><slf4j.version>1.7.36</slf4j.version><snakeyaml.version>1.30</snakeyaml.version><solr.version>8.11.2</solr.version><spring-amqp.version>2.4.6</spring-amqp.version><spring-batch.version>4.3.6</spring-batch.version><spring-data-bom.version>2021.2.2</spring-data-bom.version><spring-framework.version>5.3.22</spring-framework.version><spring-graphql.version>1.0.1</spring-graphql.version><spring-hateoas.version>1.5.1</spring-hateoas.version><spring-integration.version>5.5.14</spring-integration.version><spring-kafka.version>2.8.8</spring-kafka.version><spring-ldap.version>2.4.1</spring-ldap.version><spring-restdocs.version>2.0.6.RELEASE</spring-restdocs.version><spring-retry.version>1.3.3</spring-retry.version><spring-security.version>5.7.3</spring-security.version><spring-session-bom.version>2021.2.0</spring-session-bom.version><spring-ws.version>3.1.3</spring-ws.version><sqlite-jdbc.version>3.36.0.3</sqlite-jdbc.version><sun-mail.version>1.6.7</sun-mail.version><thymeleaf.version>3.0.15.RELEASE</thymeleaf.version><thymeleaf-extras-data-attribute.version>2.0.1</thymeleaf-extras-data-attribute.version><thymeleaf-extras-java8time.version>3.0.4.RELEASE</thymeleaf-extras-java8time.version><thymeleaf-extras-springsecurity.version>3.0.4.RELEASE</thymeleaf-extras-springsecurity.version><thymeleaf-layout-dialect.version>3.0.0</thymeleaf-layout-dialect.version><tomcat.version>9.0.65</tomcat.version><unboundid-ldapsdk.version>6.0.5</unboundid-ldapsdk.version><undertow.version>2.2.19.Final</undertow.version><versions-maven-plugin.version>2.10.0</versions-maven-plugin.version><webjars-locator-core.version>0.50</webjars-locator-core.version><wsdl4j.version>1.6.3</wsdl4j.version><xml-maven-plugin.version>1.0.2</xml-maven-plugin.version><xmlunit2.version>2.9.0</xmlunit2.version></properties>

这便是SpringBoot不需要书写版本的原因！

配置依赖

<resource><directory>${basedir}/src/main/resources</directory><filtering>true</filtering><includes><include>**/application*.yml</include><include>**/application*.yaml</include><include>**/application*.properties</include></includes></resource><resource><directory>${basedir}/src/main/resources</directory><excludes><exclude>**/application*.yml</exclude><exclude>**/application*.yaml</exclude><exclude>**/application*.properties</exclude></excludes></resource>

1.2.2、启动器

springBoot的启动器：spring Boot的启动场景。

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter</artifactId></dependency>

比如：spring-boot-starter-web，它会自动导入web项目所需要的所有依赖。

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency>

spring boot会将所有的功能场景，都编程一个个的启动器，如果我们要使用什么功能，就只需要找到对应的启动器就行了。

spring官方文档：

https://docs.spring.io

1.2.3、主程序

@SpringBootApplication
public class BlogFztApplication {public static void main(String[] args) {SpringApplication.run(BlogFztApplication.class, args);}}

@SpringBootApplication:标注这个类是一个Springboot启动类，启动类下的所有资源被导入

点进去，就能看到核心注解：

注解：

@SpringBootConfiguration//springboot的配置@Configuration//spring配置类@Component//说明这也是一个spring的组件
@EnableAutoConfiguration//自动配置
//点进去@AutoConfigurationPackage//自动配置包@Import(AutoConfigurationPackages.Registrar.class)//自动配置‘包注册’@Import(AutoConfigurationImportSelector.class)//自动配置导入选择
//获取所有配置
List<String> configurations = getCandidateConfigurations(annotationMetadata,attributes);

核心方法：

获取候选的配置

protected List<String> getCandidateConfigurations(AnnotationMetadata metadata, AnnotationAttributes attributes) {List<String> configurations = new ArrayList<>(SpringFactoriesLoader.loadFactoryNames(getSpringFactoriesLoaderFactoryClass(), getBeanClassLoader()));ImportCandidates.load(AutoConfiguration.class, getBeanClassLoader()).forEach(configurations::add);Assert.notEmpty(configurations,//断言非空，如果配置文件不为空，则去找spring.factories文件"No auto configuration classes found in META-INF/spring.factories nor in META-INF/spring/org.springframework.boot.autoconfigure.AutoConfiguration.imports. If you "+ "are using a custom packaging, make sure that file is correct.");return configurations;}

protected Class<?> getSpringFactoriesLoaderFactoryClass() {return EnableAutoConfiguration.class;}

META-INF/spring.factories:org.springframework.boot.autoconfigure

# Initializers
org.springframework.context.ApplicationContextInitializer=\
org.springframework.boot.autoconfigure.SharedMetadataReaderFactoryContextInitializer,\
org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingListener# Application Listeners
org.springframework.context.ApplicationListener=\
org.springframework.boot.autoconfigure.BackgroundPreinitializer# Environment Post Processors
org.springframework.boot.env.EnvironmentPostProcessor=\
org.springframework.boot.autoconfigure.integration.IntegrationPropertiesEnvironmentPostProcessor# Auto Configuration Import Listeners
org.springframework.boot.autoconfigure.AutoConfigurationImportListener=\
org.springframework.boot.autoconfigure.condition.ConditionEvaluationReportAutoConfigurationImportListener# Auto Configuration Import Filters
org.springframework.boot.autoconfigure.AutoConfigurationImportFilter=\
org.springframework.boot.autoconfigure.condition.OnBeanCondition,\
org.springframework.boot.autoconfigure.condition.OnClassCondition,\
org.springframework.boot.autoconfigure.condition.OnWebApplicationCondition# Failure analyzers
org.springframework.boot.diagnostics.FailureAnalyzer=\
org.springframework.boot.autoconfigure.data.redis.RedisUrlSyntaxFailureAnalyzer,\
org.springframework.boot.autoconfigure.diagnostics.analyzer.NoSuchBeanDefinitionFailureAnalyzer,\
org.springframework.boot.autoconfigure.flyway.FlywayMigrationScriptMissingFailureAnalyzer,\
org.springframework.boot.autoconfigure.jdbc.DataSourceBeanCreationFailureAnalyzer,\
org.springframework.boot.autoconfigure.jdbc.HikariDriverConfigurationFailureAnalyzer,\
org.springframework.boot.autoconfigure.jooq.NoDslContextBeanFailureAnalyzer,\
org.springframework.boot.autoconfigure.r2dbc.ConnectionFactoryBeanCreationFailureAnalyzer,\
org.springframework.boot.autoconfigure.r2dbc.MissingR2dbcPoolDependencyFailureAnalyzer,\
org.springframework.boot.autoconfigure.r2dbc.MultipleConnectionPoolConfigurationsFailureAnalzyer,\
org.springframework.boot.autoconfigure.r2dbc.NoConnectionFactoryBeanFailureAnalyzer,\
org.springframework.boot.autoconfigure.session.NonUniqueSessionRepositoryFailureAnalyzer# Template availability providers
org.springframework.boot.autoconfigure.template.TemplateAvailabilityProvider=\
org.springframework.boot.autoconfigure.freemarker.FreeMarkerTemplateAvailabilityProvider,\
org.springframework.boot.autoconfigure.mustache.MustacheTemplateAvailabilityProvider,\
org.springframework.boot.autoconfigure.groovy.template.GroovyTemplateAvailabilityProvider,\
org.springframework.boot.autoconfigure.thymeleaf.ThymeleafTemplateAvailabilityProvider,\
org.springframework.boot.autoconfigure.web.servlet.JspTemplateAvailabilityProvider# DataSource initializer detectors
org.springframework.boot.sql.init.dependency.DatabaseInitializerDetector=\
org.springframework.boot.autoconfigure.flyway.FlywayMigrationInitializerDatabaseInitializerDetector# Depends on database initialization detectors
org.springframework.boot.sql.init.dependency.DependsOnDatabaseInitializationDetector=\
org.springframework.boot.autoconfigure.batch.JobRepositoryDependsOnDatabaseInitializationDetector,\
org.springframework.boot.autoconfigure.quartz.SchedulerDependsOnDatabaseInitializationDetector,\
org.springframework.boot.autoconfigure.session.JdbcIndexedSessionRepositoryDependsOnDatabaseInitializationDetector

Properties properties = PropertiesLoaderUtils.loadProperties(resource);