上一篇已經簡單介紹了啓動類的部分,這一篇主要討論一下springboot引入的哪些依賴java
咱們都知道想用springboot作一個web應用,首先要作的是引入相關依賴,兩步操做:git
一、添加spring-boot-starter-parentgithub
二、引入spring-boot-starter-webweb
至此全部關於web的依賴所有應用完畢spring
之前咱們在用spring的時候,還須要添加不少依賴,包括spring-webmvc、spring-context、spring-bean等等,爲何到springboot就只須要這兩個了呢?apache
如今來一探究竟json
先從spring-boot-starter-parent開始,先貼一下源碼tomcat
<?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> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>2.1.1.RELEASE</version> <relativePath>../../spring-boot-dependencies</relativePath> </parent> <artifactId>spring-boot-starter-parent</artifactId> <packaging>pom</packaging> <name>Spring Boot Starter Parent</name> <description>Parent pom providing dependency and plugin management for applications built with Maven</description> <url>https://projects.spring.io/spring-boot/#/spring-boot-starter-parent</url> <properties> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> <resource.delimiter>@</resource.delimiter> <maven.compiler.source>${java.version}</maven.compiler.source> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <maven.compiler.target>${java.version}</maven.compiler.target> </properties> <build> <resources> <resource> <filtering>true</filtering> <directory>${basedir}/src/main/resources</directory> <includes> <include>**/application*.yml</include> <include>**/application*.yaml</include> <include>**/application*.properties</include> </includes> </resource> <resource> <directory>${basedir}/src/main/resources</directory> <excludes> <exclude>**/application*.yml</exclude> <exclude>**/application*.yaml</exclude> <exclude>**/application*.properties</exclude> </excludes> </resource> </resources> <pluginManagement> <plugins> <plugin> <groupId>org.jetbrains.kotlin</groupId> <artifactId>kotlin-maven-plugin</artifactId> <version>${kotlin.version}</version> <executions> <execution> <id>compile</id> <phase>compile</phase> <goals> <goal>compile</goal> </goals> </execution> <execution> <id>test-compile</id> <phase>test-compile</phase> <goals> <goal>test-compile</goal> </goals> </execution> </executions> <configuration> <jvmTarget>${java.version}</jvmTarget> <javaParameters>true</javaParameters> </configuration> </plugin> <plugin> <artifactId>maven-compiler-plugin</artifactId> <configuration> <parameters>true</parameters> </configuration> </plugin> <plugin> <artifactId>maven-failsafe-plugin</artifactId> <executions> <execution> <goals> <goal>integration-test</goal> <goal>verify</goal> </goals> </execution> </executions> <configuration> <classesDirectory>${project.build.outputDirectory}</classesDirectory> </configuration> </plugin> <plugin> <artifactId>maven-jar-plugin</artifactId> <configuration> <archive> <manifest> <mainClass>${start-class}</mainClass> <addDefaultImplementationEntries>true</addDefaultImplementationEntries> </manifest> </archive> </configuration> </plugin> <plugin> <artifactId>maven-war-plugin</artifactId> <configuration> <archive> <manifest> <mainClass>${start-class}</mainClass> <addDefaultImplementationEntries>true</addDefaultImplementationEntries> </manifest> </archive> </configuration> </plugin> <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>exec-maven-plugin</artifactId> <configuration> <mainClass>${start-class}</mainClass> </configuration> </plugin> <plugin> <artifactId>maven-resources-plugin</artifactId> <configuration> <delimiters> <delimiter>${resource.delimiter}</delimiter> </delimiters> <useDefaultDelimiters>false</useDefaultDelimiters> </configuration> </plugin> <plugin> <groupId>pl.project13.maven</groupId> <artifactId>git-commit-id-plugin</artifactId> <executions> <execution> <goals> <goal>revision</goal> </goals> </execution> </executions> <configuration> <verbose>true</verbose> <dateFormat>yyyy-MM-dd'T'HH:mm:ssZ</dateFormat> <generateGitPropertiesFile>true</generateGitPropertiesFile> <generateGitPropertiesFilename>${project.build.outputDirectory}/git.properties</generateGitPropertiesFilename> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <executions> <execution> <id>repackage</id> <goals> <goal>repackage</goal> </goals> </execution> </executions> <configuration> <mainClass>${start-class}</mainClass> </configuration> </plugin> <plugin> <artifactId>maven-shade-plugin</artifactId> <executions> <execution> <phase>package</phase> <goals> <goal>shade</goal> </goals> <configuration> <transformers> <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer"> <resource>META-INF/spring.handlers</resource> </transformer> <transformer implementation="org.springframework.boot.maven.PropertiesMergingResourceTransformer"> <resource>META-INF/spring.factories</resource> </transformer> <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer"> <resource>META-INF/spring.schemas</resource> </transformer> <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/> <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer"> <mainClass>${start-class}</mainClass> </transformer> </transformers> </configuration> </execution> </executions> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>2.1.1.RELEASE</version> </dependency> </dependencies> <configuration> <keepDependenciesWithProvidedScope>true</keepDependenciesWithProvidedScope> <createDependencyReducedPom>true</createDependencyReducedPom> <filters> <filter> <artifact>*:*</artifact> <excludes> <exclude>META-INF/*.SF</exclude> <exclude>META-INF/*.DSA</exclude> <exclude>META-INF/*.RSA</exclude> </excludes> </filter> </filters> </configuration> </plugin> <plugin> <groupId>org.eclipse.m2e</groupId> <artifactId>lifecycle-mapping</artifactId> <version>1.0.0</version> <configuration> <lifecycleMappingMetadata> <pluginExecutions> <pluginExecution> <pluginExecutionFilter> <groupId>org.codehaus.mojo</groupId> <artifactId>flatten-maven-plugin</artifactId> <versionRange>[1.0.0,)</versionRange> <goals> <goal>flatten</goal> </goals> </pluginExecutionFilter> <action> <ignore/> </action> </pluginExecution> <pluginExecution> <pluginExecutionFilter> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-checkstyle-plugin</artifactId> <versionRange>[3.0.0,)</versionRange> <goals> <goal>check</goal> </goals> </pluginExecutionFilter> <action> <ignore/> </action> </pluginExecution> </pluginExecutions> </lifecycleMappingMetadata> </configuration> </plugin> </plugins> </pluginManagement> </build> </project>
首先看到的是spring-boot-starter-parent竟然還有parent,這個先稍後再說。springboot
而後看到的是<build>標籤,這裏定義了哪些會被打包到jar裏,指定了一堆plugin來幫助打包和編譯mvc
plugin有興趣的能夠研究,重點說一下配置文件的指定。
看到.yml、.yaml,.properties三種格式配置文件,當一個工程的resources下同時存在這三種文件時,優先加載的是.properties文件,爲何這麼說呢,由於spring有個覆蓋原則,後邊的配置會覆蓋掉前邊,就算先加載.yml文件的內容,只要是相同的配置,依然會被後邊的覆蓋掉,可是不一樣的配置會被保留。
什麼意思呢?舉個例來講明一下,如今項目裏有這樣一個controller和三個配置文件
properties文件裏下的內容是
yaml文件裏內容是
yml文件裏的內容是
然而最終啓動時用的端口是
訪問接口打印的是
說明properties>yml>yaml,另外不一樣路徑也有不同的優先級-file:/config/>-file:./>-classpath:/config/>-classpath:/
固然,有其餘方式指定配置文件,有機會單獨詳細介紹
下面是spring-boot-starter-web的pom文件這裏只是引入了springweb項目須要用的依賴,並無什麼好說的。
<?xml version="1.0" encoding="UTF-8"?> <project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starters</artifactId> <version>2.1.9.RELEASE</version> </parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> <version>2.1.9.RELEASE</version> <name>Spring Boot Web Starter</name> <description>Starter for building web, including RESTful, applications using Spring MVC. Uses Tomcat as the default embedded container</description> <url>https://projects.spring.io/spring-boot/#/spring-boot-parent/spring-boot-starters/spring-boot-starter-web</url> <organization> <name>Pivotal Software, Inc.</name> <url>https://spring.io</url> </organization> <licenses> <license> <name>Apache License, Version 2.0</name> <url>https://www.apache.org/licenses/LICENSE-2.0</url> </license> </licenses> <developers> <developer> <name>Pivotal</name> <email>info@pivotal.io</email> <organization>Pivotal Software, Inc.</organization> <organizationUrl>https://www.spring.io</organizationUrl> </developer> </developers> <scm> <connection>scm:git:git://github.com/spring-projects/spring-boot.git</connection> <developerConnection>scm:git:ssh://git@github.com/spring-projects/spring-boot.git</developerConnection> <url>https://github.com/spring-projects/spring-boot</url> </scm> <issueManagement> <system>Github</system> <url>https://github.com/spring-projects/spring-boot/issues</url> </issueManagement> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> <version>2.1.9.RELEASE</version> <scope>compile</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-json</artifactId> <version>2.1.9.RELEASE</version> <scope>compile</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> <version>2.1.9.RELEASE</version> <scope>compile</scope> </dependency> <dependency> <groupId>org.hibernate.validator</groupId> <artifactId>hibernate-validator</artifactId> <version>6.0.17.Final</version> <scope>compile</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>5.1.10.RELEASE</version> <scope>compile</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>5.1.10.RELEASE</version> <scope>compile</scope> </dependency> </dependencies> </project>
至此就是spring-boot-start-web的所有內容