前言

我們在做java專案的時候由於jar包太多，我們就需要使用maven做專案管理，管理專案的jar包依賴，包括打包上線

maven基礎

Maven 是一個專案管理工具，主要用於專案構建，依賴管理，專案資訊管理

每個maven 專案根目錄都會有一個 pom.xml檔案， 負責專案構建，依賴管理

在這個檔案裡面，你只需要新增相應的jar包座標配置，maven就會自動幫你下載相應jar包，不需要我們手動去構建新增jar包很方面，尤其在專案很大，需要jar包依賴很多時候，根本離不開maven

在maven的程式碼庫中，每一個jar包也有自己的 pom.xml檔案配置，只要你配置的jar包所依賴的其他jar包都會被maven自動下載下來。

這裡會涉及到問題maven多模組實現以及迴圈依賴 後面會講解

    <dependency>

      <groupId>cn.soboys</groupId>  專案組專案所在團隊

      <artifactId>kmall</artifactId>  專案具體名稱模組名

      <version>1.0-SNAPSHOT</version>  專案版本號

    </dependency>

maven都會通過，<groupId>-<artifactId>-<version>座標來定位一個jar包

在maven網際網路倉庫上，並進行下載

Maven 會根據 POM 檔案自動下載所需 JAR 包。如果以後你在本地其它專案中也使用此 JAR 包，那麼 Maven 會首先檢查本地是否有 JAR 包，如果沒有再從中央倉庫下載。

maven 專案結構命令

1. src/main/java - 存放專案.java檔案；
2. src/main/resources - 存放專案資原始檔；
3. src/test/java - 存放測試類.java檔案；
4. src/test/resources - 存放測試資原始檔；
5. target - 專案輸出目錄；
6. pom.xml - Maven核心檔案（Project Object Model）；

maven常用命令

1. mvn archetype：create 建立Maven專案
2. mvn compile 編譯原始碼
3. mvn deploy 釋出專案
4. mvn test-compile 編譯測試原始碼
5. mvn test 執行應用程式中的單元測試
6. mvn site 生成專案相關資訊的網站
7. mvn clean 清除專案目錄中的生成結果
8. mvn package 根據專案生成的jar
9. mvn install 在本地Repository中安裝jar
10. mvn eclipse:eclipse 生成eclipse專案檔案
11. mvnjetty:run 啟動jetty服務
12. mvntomcat:run 啟動tomcat服務
13. mvn clean package -Dmaven.test.skip=true 清除以前的包後重新打包，跳過測試類

maven 常用標籤

parent標籤

在maven多模組專案中引用父pom依賴，在springboot專案中就有父依賴

  <!--引用springBoot父專案-->

    <parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

        <version>2.4.7</version>

        <relativePath/> <!-- lookup parent from repository -->

    </parent>

properties標籤

定義一些全域性屬性值，常用於jar包版本定義全域性管理jar包版本後面可以${} 取值

在springboot專案中父pom會定義一些專案jar包版本依賴 ，所以我們在引用jar時候才不用寫jar包版本，會自動跟隨父pom中定義的jar包版本

<parent>

    <groupId>org.springframework.boot</groupId>

    <artifactId>spring-boot-dependencies</artifactId>

    <version>2.4.7</version>

  </parent>

<properties>

    <activemq.version>5.16.2</activemq.version>

    <antlr2.version>2.7.7</antlr2.version>

    <appengine-sdk.version>1.9.89</appengine-sdk.version>

    <artemis.version>2.15.0</artemis.version>

    <aspectj.version>1.9.6</aspectj.version>

    <assertj.version>3.18.1</assertj.version>

    <atomikos.version>4.0.6</atomikos.version>

    <awaitility.version>4.0.3</awaitility.version>

    <bitronix.version>2.1.4</bitronix.version>

    <build-helper-maven-plugin.version>3.2.0</build-helper-maven-plugin.version>

    <byte-buddy.version>1.10.22</byte-buddy.version>

    <caffeine.version>2.8.8</caffeine.version>

    <cassandra-driver.version>4.9.0</cassandra-driver.version>

    <classmate.version>1.5.1</classmate.version>

    <commons-codec.version>1.15</commons-codec.version>

    <commons-dbcp2.version>2.8.0</commons-dbcp2.version>

    <commons-lang3.version>3.11</commons-lang3.version>

    <commons-pool.version>1.6</commons-pool.version>

    <commons-pool2.version>2.9.0</commons-pool2.version>

    <couchbase-client.version>3.0.10</couchbase-client.version>

    <db2-jdbc.version>11.5.5.0</db2-jdbc.version>

    <dependency-management-plugin.version>1.0.11.RELEASE</dependency-management-plugin.version>

    <derby.version>10.14.2.0</derby.version>

    <dropwizard-metrics.version>4.1.22</dropwizard-metrics.version>

    <ehcache.version>2.10.9.2</ehcache.version>

    <ehcache3.version>3.9.4</ehcache3.version>

    <elasticsearch.version>7.9.3</elasticsearch.version>

    <embedded-mongo.version>2.2.0</embedded-mongo.version>

    <flyway.version>7.1.1</flyway.version>

    <freemarker.version>2.3.31</freemarker.version>

    <git-commit-id-plugin.version>3.0.1</git-commit-id-plugin.version>

    <glassfish-el.version>3.0.3</glassfish-el.version>

    <glassfish-jaxb.version>2.3.4</glassfish-jaxb.version>

    <groovy.version>2.5.14</groovy.version>

    <gson.version>2.8.7</gson.version>

    <h2.version>1.4.200</h2.version>

    <hamcrest.version>2.2</hamcrest.version>

    <hazelcast.version>4.0.3</hazelcast.version>

    <hazelcast-hibernate5.version>2.1.1</hazelcast-hibernate5.version>

    <hibernate.version>5.4.32.Final</hibernate.version>

    <hibernate-validator.version>6.1.7.Final</hibernate-validator.version>

    <hikaricp.version>3.4.5</hikaricp.version>

    <hsqldb.version>2.5.2</hsqldb.version>

    <htmlunit.version>2.44.0</htmlunit.version>

    <httpasyncclient.version>4.1.4</httpasyncclient.version>

    <httpclient.version>4.5.13</httpclient.version>

    <httpcore.version>4.4.14</httpcore.version>

    <infinispan.version>11.0.11.Final</infinispan.version>

    <influxdb-java.version>2.20</influxdb-java.version>

    <jackson-bom.version>2.11.4</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-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>3.1.4</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>3.0.11</jaybird.version>

    <jboss-logging.version>3.4.2.Final</jboss-logging.version>

    <jboss-transaction-spi.version>7.6.1.Final</jboss-transaction-spi.version>

    <jdom2.version>2.0.6</jdom2.version>

    <jedis.version>3.3.0</jedis.version>

    <jersey.version>2.32</jersey.version>

    <jetty-el.version>8.5.54</jetty-el.version>

    <jetty-jsp.version>2.2.0.v201112011158</jetty-jsp.version>

    <jetty-reactive-httpclient.version>1.1.9</jetty-reactive-httpclient.version>

    <jetty.version>9.4.42.v20210604</jetty.version>

    <jmustache.version>1.15</jmustache.version>

    <johnzon.version>1.2.13</johnzon.version>

    <jolokia.version>1.6.2</jolokia.version>

    <jooq.version>3.14.11</jooq.version>

    <json-path.version>2.4.0</json-path.version>

    <json-smart.version>2.3.1</json-smart.version>

    <jsonassert.version>1.5.0</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>5.7.2</junit-jupiter.version>

    <kafka.version>2.6.2</kafka.version>

    <kotlin.version>1.4.32</kotlin.version>

    <kotlin-coroutines.version>1.4.3</kotlin-coroutines.version>

    <lettuce.version>6.0.5.RELEASE</lettuce.version>

    <liquibase.version>3.10.3</liquibase.version>

    <log4j2.version>2.13.3</log4j2.version>

    <logback.version>1.2.3</logback.version>

    <lombok.version>1.18.20</lombok.version>

    <mariadb.version>2.7.3</mariadb.version>

    <maven-antrun-plugin.version>1.8</maven-antrun-plugin.version>

    <maven-assembly-plugin.version>3.3.0</maven-assembly-plugin.version>

    <maven-clean-plugin.version>3.1.0</maven-clean-plugin.version>

    <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>

    <maven-dependency-plugin.version>3.1.2</maven-dependency-plugin.version>

    <maven-deploy-plugin.version>2.8.2</maven-deploy-plugin.version>

    <maven-enforcer-plugin.version>3.0.0-M3</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>3.2.0</maven-jar-plugin.version>

    <maven-javadoc-plugin.version>3.2.0</maven-javadoc-plugin.version>

    <maven-resources-plugin.version>3.2.0</maven-resources-plugin.version>

    <maven-shade-plugin.version>3.2.4</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>3.3.1</maven-war-plugin.version>

    <micrometer.version>1.6.7</micrometer.version>

    <mimepull.version>1.9.14</mimepull.version>

    <mockito.version>3.6.28</mockito.version>

    <mongodb.version>4.1.2</mongodb.version>

    <mssql-jdbc.version>8.4.1.jre8</mssql-jdbc.version>

    <mysql.version>8.0.25</mysql.version>

    <nekohtml.version>1.9.22</nekohtml.version>

    <neo4j-java-driver.version>4.1.3</neo4j-java-driver.version>

    <netty.version>4.1.65.Final</netty.version>

    <netty-tcnative.version>2.0.39.Final</netty-tcnative.version>

    <oauth2-oidc-sdk.version>8.36.1</oauth2-oidc-sdk.version>

    <nimbus-jose-jwt.version>8.20.2</nimbus-jose-jwt.version>

    <ojdbc.version>19.3.0.0</ojdbc.version>

    <okhttp3.version>3.14.9</okhttp3.version>

    <oracle-database.version>19.8.0.0</oracle-database.version>

    <pooled-jms.version>1.2.2</pooled-jms.version>

    <postgresql.version>42.2.20</postgresql.version>

    <prometheus-pushgateway.version>0.9.0</prometheus-pushgateway.version>

    <quartz.version>2.3.2</quartz.version>

    <querydsl.version>4.4.0</querydsl.version>

    <r2dbc-bom.version>Arabba-SR10</r2dbc-bom.version>

    <rabbit-amqp-client.version>5.10.0</rabbit-amqp-client.version>

    <reactive-streams.version>1.0.3</reactive-streams.version>

    <reactor-bom.version>2020.0.7</reactor-bom.version>

    <rest-assured.version>3.3.0</rest-assured.version>

    <rsocket.version>1.1.1</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>3.141.59</selenium.version>

    <selenium-htmlunit.version>2.44.0</selenium-htmlunit.version>

    <sendgrid.version>4.6.8</sendgrid.version>

    <servlet-api.version>4.0.1</servlet-api.version>

    <slf4j.version>1.7.30</slf4j.version>

    <snakeyaml.version>1.27</snakeyaml.version>

    <solr.version>8.5.2</solr.version>

    <spring-amqp.version>2.3.8</spring-amqp.version>

    <spring-batch.version>4.3.3</spring-batch.version>

    <spring-data-bom.version>2020.0.9</spring-data-bom.version>

    <spring-framework.version>5.3.8</spring-framework.version>

    <spring-hateoas.version>1.2.6</spring-hateoas.version>

    <spring-integration.version>5.4.7</spring-integration.version>

    <spring-kafka.version>2.6.9</spring-kafka.version>

    <spring-ldap.version>2.3.4.RELEASE</spring-ldap.version>

    <spring-restdocs.version>2.0.5.RELEASE</spring-restdocs.version>

    <spring-retry.version>1.3.1</spring-retry.version>

    <spring-security.version>5.4.6</spring-security.version>

    <spring-session-bom.version>2020.0.4</spring-session-bom.version>

    <spring-ws.version>3.0.10.RELEASE</spring-ws.version>

    <sqlite-jdbc.version>3.32.3.3</sqlite-jdbc.version>

    <sun-mail.version>1.6.7</sun-mail.version>

    <thymeleaf.version>3.0.12.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>2.5.3</thymeleaf-layout-dialect.version>

    <tomcat.version>9.0.46</tomcat.version>

    <unboundid-ldapsdk.version>4.0.14</unboundid-ldapsdk.version>

    <undertow.version>2.2.8.Final</undertow.version>

    <versions-maven-plugin.version>2.8.1</versions-maven-plugin.version>

    <webjars-hal-browser.version>3325375</webjars-hal-browser.version>

    <webjars-locator-core.version>0.46</webjars-locator-core.version>

    <wsdl4j.version>1.6.3</wsdl4j.version>

    <xml-maven-plugin.version>1.0.2</xml-maven-plugin.version>

    <xmlunit2.version>2.7.0</xmlunit2.version>

  </properties>

dependencyManagement標籤

在Maven多模組的時候，管理依賴關係是非常重要的，各種依賴包衝突，查詢問題起來非常複雜，於是就用到了，

在springboot專案中父模組就定義了

  <dependencyManagement>

        <dependencies>

             <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-activemq</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-actuator</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-amqp</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-aop</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-artemis</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-batch</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-cache</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-cassandra</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-cassandra-reactive</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-couchbase</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-couchbase-reactive</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-elasticsearch</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-jdbc</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-jpa</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-ldap</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-mongodb</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-mongodb-reactive</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-r2dbc</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-redis</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-redis-reactive</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-neo4j</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-rest</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-data-solr</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-freemarker</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-groovy-templates</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-hateoas</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-integration</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jdbc</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jersey</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jetty</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jooq</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-json</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jta-atomikos</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-jta-bitronix</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-log4j2</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-logging</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-mail</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-mustache</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-oauth2-client</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-oauth2-resource-server</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-quartz</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-reactor-netty</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-rsocket</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-security</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-test</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-thymeleaf</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-tomcat</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-undertow</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-validation</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-webflux</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-websocket</artifactId>

            <version>2.4.7</version>

          </dependency>

          <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web-services</artifactId>

            <version>2.4.7</version>

          </dependency>

        </dependencies>

</dependencyManagement>

那麼在子模組中只需要<groupId>和<artifactId>即可，也就是我們建立springboot專案中

 <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-aop</artifactId>

        </dependency>

使用dependencyManagement可以統一管理專案的版本號，確保應用的各個專案的依賴和版本一致，不用每個模組專案都弄一個版本號，不利於管理，當需要變更版本號的時候只需要在父類容器裡更新，不需要任何一個子專案的修改；如果某個子專案需要另外一個特殊的版本號時，只需要在自己的模組dependencies中宣告一個版本號即可。子類就會使用子類宣告的版本號，不繼承於父類版本號

dependencies標籤

用於引入專案依賴

  <dependencies>

        <!--aop 切面-->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-aop</artifactId>

        </dependency>

        <!--ip獲取位置-->

    </dependencies>

注意

Dependencies相對於dependencyManagement，所有生命在dependencies裡的依賴都會自動引入，並預設被所有的子專案繼承。

而dependencyManagement裡只是宣告依賴，並不自動實現引入，因此子專案需要顯示的宣告需要用的依賴。

如果不在子專案中宣告依賴，是不會從父專案中繼承下來的；只有在子專案中寫了該依賴項，並且沒有指定具體版本，才會從父專案中繼承該項，並且version和scope都讀取自父pom;另外如果子專案中指定了版本號，那麼會使用子專案中指定的jar版本。

maven衝突解決

我們可以通過exclusions 標籤過濾掉不需要的依賴

<dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

            <exclusions>

                <exclusion>

                    <groupId>org.springframework.boot</groupId>

                    <artifactId>spring-boot-starter-logging</artifactId>

                </exclusion>

                <exclusion>

                    <groupId>org.springframework.boot</groupId>

                    <artifactId>spring-boot-starter-tomcat</artifactId>

                </exclusion>

            </exclusions>

  </dependency>

maven打包和外掛

下面列舉的常用打包和外掛

 <!--打包-->

    <build>

       <resources>

        <resource>

            <filtering>true</filtering>

            <directory>src/main/resources</directory>

        </resource>

    </resources>

        <plugins>

            <plugin>

                <groupId>org.apache.maven.plugins</groupId>

                <artifactId>maven-compiler-plugin</artifactId>

                <version>${maven.compiler.plugin.version}</version>

                <configuration>

                    <source>${java.version}</source>

                    <target>${java.version}</target>

                    <encoding>${project.build.sourceEncoding}</encoding>

                </configuration>

            </plugin>

            <plugin>

                <groupId>org.apache.maven.plugins</groupId>

                <artifactId>maven-resources-plugin</artifactId>

                <version>${maven.resources.plugin.version}</version>

                <configuration>

                    <encoding>${project.build.sourceEncoding}</encoding>

                </configuration>

            </plugin>

            <plugin>

                <groupId>org.apache.maven.plugins</groupId>

                <artifactId>maven-jar-plugin</artifactId>

                <version>${maven.jar.plugin.version}</version>

            </plugin>

           <!-- <plugin>

                <artifactId>maven-war-plugin</artifactId>

                <version>${maven-war-plugin.version}</version>

                <configuration> &lt;!&ndash; Exclude JCL and LOG4J since all logging should go through SLF4J. Note that we're excluding log4j-<version>.jar but keeping log4j-over-slf4j-<version>.jar &ndash;&gt;

                    <packagingExcludes>

                        WEB-INF/lib/hutool-setting.jar,

                    </packagingExcludes>

                </configuration>

            </plugin>-->

            <plugin>

                <groupId>org.springframework.boot</groupId>

                <artifactId>spring-boot-maven-plugin</artifactId>

                <executions>

                    <execution>

                        <goals>

                            <goal>repackage</goal><!--可以把依賴的包都打包到生成的Jar包中-->

                        </goals>

                    </execution>

                </executions>

            </plugin>

        </plugins>

    </build>