Spring Quick Start & Introduction to Maven

2018.4.16

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First, before getting started, we need to understand Maven.
1. Maven model The

picture comes from the
basic concept of Maven on the Internet
- Project: Anything you want to build, Maven can consider them as a project, and these projects are identified as project model objects (Project Object Model, POM). A project can depend on other projects, and a project can also be composed of multiple sub-projects.
- POM: POM (pom.xml) is the core file of Maven, it is a metadata file that instructs how Maven works, similar to the build.xml file in Ant. POM files are located in the root directory of every project.
- GroupId: GroupId is the unique identifier of a project in the world. Generally, it is the project name. It is useful to use a full package name to distinguish a project from other similarly named projects.
- Artifact: Chinese name, component. Is the file that the project will produce or need to use, it can be a .jar file, a source file, a binary file, a .war file, or even a .pom file. Each Artifact is uniquely identified by a combination of GroupId and Artifact identifier. Artifacts that need to be used must be placed in the Repository, otherwise Maven will not be able to find them.
- Dependency: A typical Java project will depend on other packages in order to be able to build or wrap. Dependency is generally the Artifact of other projects.
- Plug-in: It can be said that Maven is a collection of plug-ins, each of its functions is completed by the plug-in, the plug-in provides goals, and completes the work according to the metadata found in the POM.
- Repository: Warehouse, where Artifact is placed, there are central warehouses, public warehouses, private warehouses, and local warehouses. Generally, in order to improve the download speed, there will be a private warehouse.

<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>springdemo</groupId>
  <artifactId>springdemo1</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>springdemo1</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>

    <!-- Spring Core -->
        <!-- http://mvnrepository.com/artifact/org.springframework/spring-core -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>4.1.4.RELEASE</version>
        </dependency>

        <!-- Spring Context -->
        <!-- http://mvnrepository.com/artifact/org.springframework/spring-context -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.1.4.RELEASE</version>
        </dependency>
  </dependencies>
</project>

This is a pom.xml file I wrote when I was doing the demo.