Maven getting started

1. What is Maven?

Maven English name: Expert, visible by name, this tool is ambitious. Someone said that he is a "build tool", a tool used to build source code into a publishable component. Some people also say it is a project management tool.

Official definition:

Maven is a project management tool that contains a project object model, a set of standard sets, and a project life cycle ), A dependency management system and logic used to run the plug-in (GOAL) defined in the lifecycle phase (phase.

I understand:

Maven built-in software repository to help build packaging management projects.

Ii. Install Maven in Linux 1. Java environment.

Set java_home

In ~ /. Add to bashrc

Export java_home =/usr/lib/JVM/java-1.6.0-openjdk-1.6.0.0.x86_64/

Ensure that Java commands are available. If not, install Yum install openjdk-devel.

2. Download Maven.

Http://maven.apache.org/download.html

Unzip to:/opt/apache-maven-3.0.3/

Set environment variables and add ~ /. Bashrc

Export m2_home =/opt/apache-maven-3.0.3/

Export Path = $ path:/opt/apache-maven-3.0.3/bin/

Execute .~. /Bashrc.

3. Check whether the test is successful.

4. Install Maven in eclipse

On the official download page, you can find the address to update m2eclipse in eclispe: http://download.eclipse.org/technology/m2e/releases

Open eclipse -- help --> install new software --> Add --> name input Maven, location input http://download.eclipse.org/technology/m2e/releases

Click Next and select the part to be installed.

Verify whether the installation is successful:

File, enter the filtering condition Maven, and check the maven option, indicating that the installation is successful.

Let eclipse use Maven runtime installed externally

Windows --> preferences --> Find Maven project --> Installation Project, click Add, and find the local Maven location.

Iii. Use 1. Conventions are better than configurations

Convention over configuration

The source code is assumed to be in/src/main/Java,

The resource file is assumed to be in src/main/Resources

The test code is assumed to be in/src/test.

Project assumes that a jar file is generated.

Maven assumes that you want to put the compiled byte code to/target/classes

Create a distributable JAR file in/target.

It seems nothing, but it is much easier to use than ant. Ant needs to configure each directory. Of course there are more than these differences.

Shows the default structure:

2. Create a Maven Project Create with command

MVN archetype: Create-dgroupid = WZ. Package-dartifactid = helloworld

Added a WEB Project:-darchetypeartifactid = Maven-Archetype-webapp

Groupid group name, dartifactid project name.

Generate Pom. XML as follows:

 

1. <Modelversion> 4.0.0 </modelversion>
2. <Groupid> mygroup </groupid>
3. <Packaging> jar </packaging>
4. <URL> http://maven.apache.org </URL>
5. <Properties>
6. <Project. Build. sourceencoding> UTF-8 </Project. Build. sourceencoding>
7. </Properties>
8. <Dependencies>
9. <Dependency>
10. <Groupid> JUnit </groupid>
11. <Artifactid> JUnit </artifactid>
12. <Version> 3.8.1 </version>
13. <Scope> test </scope>
14. </Dependency>
15. </Dependencies>
16. </Project>

 

Write a helloworld

• MVN clean compile and generate target

Use eclipse Maven plug-in to create project 1.new project select Maven project2 to create simple project3. enter basic information and click Finish. The generated directory structure is as follows: 3 test:

@ Test

Public void testsayhello (){

App = new app ();

String result = app. sayhello ();

Assert. assertequals ("Hello Maven! ", Result );

}

• MVN clean test

4. Search for available versions

• Http://mvnrepository.com/

• For example, you can find many versions of JUnit and click to view them.

5 packaging and Installation

MVN clean package

MVN clean install

MVN jetty: Run (web project running)

Complex example:

Org. springframework. samples. jpetstore (complex)

6. Scope of Project Dependencies

Compile (compilation range) Compile is the default range;

Provided (provided scope) such as Servlet

Runtime (runtime range), such as JDBC Implementation Package

Test (test scope)

System)

4. FAQs 1. Web project Conversion

MVN Eclipse: eclipse is converted into an Eclipse project and cannot be identified as a web project. Use the following command:

MVN Eclipse: eclipse-dwtpversion = 1.0

2. Do not recognize m2_repo

The m2_repo parameter is not recognized by eclipse and needs to be added to it:

Eclipse-> Windows-> preferences-> JAVA-> build path-> classpath Variables

The name is m2_repo, and the property is folder, pointing to c: \ Documents and Settings \ kaseyxiong \. m2 \ Repository

3. Dependency packages are not imported during eclipse deployment.

This problem is usually not encountered. If so, the project -- properties -- deployment assembly --> Add --> build path entries --> select the required package --> finish

4. eclipse not compiled

Project --.> just clean

5. Download the source code of the dependent package

Add the parameter-ddownloadsources = true or MVN dependency: sources.

Maven getting started