java项目构建工具Maven

一、java-maven常用命令

mvn archetype：create 创建Maven项目
mvn compile 编译源代码
mvn deploy 发布项目
mvn test-compile 编译测试源代码
mvn test 运行应用程序中的单元测试
mvn site 生成项目相关信息的网站
mvn clean 清除项目目录中的生成结果
mvn package 根据项目生成的jar
mvn install 在本地Repository中安装jar
mvn eclipse:eclipse 生成eclipse项目文件
mvnjetty:run 启动jetty服务
mvntomcat:run 启动tomcat服务

二、利用java-maven创建一个最简单的Hello World项目。

1、编写pom文件

首先创建一个名为hello-world的文件夹，打开该文件夹，新建一个名为pom.xml的文件，输入其内容如代码如下：

<?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/maven-v4_0_0.xsd"> 
    <modelVersion>4.0.0</modelVersion> 
    <groupId>com.juvenxu.mvnbook</groupId> 
    <artifactId>hello-world</artifactId> 
    <version>1.0-SNAPSHOT</version> 
    <name>Maven Hello World Project</name> 
    <dependencies> 
        <dependency> 
            <groupId>junit</groupId> 
            <artifactId>junit</artifactId> 
            <version>4.7</version> 
            <scope>test</scope> 
        </dependency> 
    </dependencies> 
    <build>
        <plugins>
            <plugin> 
                <groupId>org.apache.maven.plugins</groupId> 
                <artifactId>maven-shade-plugin</artifactId> 
                <version>1.2.1</version> 
                <executions> 
                    <execution> 
                        <phase>package</phase> 
                        <goals> 
                            <goal>shade</goal> 
                        </goals> 
                        <configuration> 
                            <transformers> 
                                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer"> 
                                    <mainClass>com.juvenxu.mvnbook.helloworld.HelloWorld</mainClass> 
                                </transformer> 
                            </transformers> 
                        </configuration> 
                    </execution> 
                </executions> 
            </plugin>
        </plugins>
    </build>
</project>

2、编写主代码

默认情况下，Maven假设项目主代码位于src/main/java目录，我们遵循Maven的约定，创建该目录，然后在该目录下创建文件com/juvenxu/mvnbook/helloworld/HelloWorld.java，其内容如下

package com.juvenxu.mvnbook.helloworld; 

public class HelloWorld {
    public String sayHello() {
        return "Hello Maven"; 
    } 

    public static void main(String[] args) { 
        System.out.print( new HelloWorld().sayHello()); 
    }
}

这是一个简单的Java类，它有一个sayHello()方法，返回一个String。同时这个类还带有一个main方法，创建一个HelloWorld实例，调用sayHello()方法，并将结果输出到控制台。

在项目根目录下运行命令 mvn clean compile ，我们会得到如下输出

[root@wangmaster hello-world]# mvn clean compile
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------< com.juvenxu.mvnbook:hello-world >-------------------
[INFO] Building Maven Hello World Project 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ hello-world ---
[INFO] Deleting /opt/project/maven/hello-world/target
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/main/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/classes
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 3.659 s
[INFO] Finished at: 2018-06-13T05:44:12+08:00
[INFO] ------------------------------------------------------------------------

3、编写测试代码 

Maven项目中默认的主代码目录是src/main/java，对应地，Maven项目中默认的测试代码目录是src/test/java。因此，在编写测试用例之前，我们先创建该目录。

在该目录下添加HelloWorldTest.java文件，内容如下

package com.juvenxu.mvnbook.helloworld; 
import static org.junit.Assert.assertEquals; 
import org.junit.Test; 

public class HelloWorldTest {
    
    @Test 
    public void testSayHello() { 
        HelloWorld helloWorld = new HelloWorld();
        String result = helloWorld.sayHello(); 

        assertEquals( "Hello Maven", result ); 
    } 
} 

测试用例编写完毕之后就可以调用Maven执行测试，运行 mvn clean test ：

[root@wangmaster hello-world]# mvn clean test
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------< com.juvenxu.mvnbook:hello-world >-------------------
[INFO] Building Maven Hello World Project 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ hello-world ---
[INFO] Deleting /opt/project/maven/hello-world/target
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/main/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/classes
[INFO] 
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/test/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/test-classes
[INFO] 
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ hello-world ---
[INFO] Surefire report directory: /opt/project/maven/hello-world/target/surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.juvenxu.mvnbook.helloworld.HelloWorldTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.212 sec

Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 5.599 s
[INFO] Finished at: 2018-06-13T05:44:24+08:00
[INFO] ------------------------------------------------------------------------

4、打包及运行

Hello World的POM中没有指定打包类型，使用默认打包类型jar，我们可以简单地执行命令 mvn clean package 进行打包。

[root@wangmaster hello-world]# mvn clean package
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------< com.juvenxu.mvnbook:hello-world >-------------------
[INFO] Building Maven Hello World Project 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-shade-plugin/1.2.1/maven-shade-plugin-1.2.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-shade-plugin/1.2.1/maven-shade-plugin-1.2.1.pom (5.8 kB at 1.9 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-plugins/13/maven-plugins-13.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-plugins/13/maven-plugins-13.pom (12 kB at 18 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-shade-plugin/1.2.1/maven-shade-plugin-1.2.1.jar
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-shade-plugin/1.2.1/maven-shade-plugin-1.2.1.jar (68 kB at 63 kB/s)
[INFO] 
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ hello-world ---
[INFO] Deleting /opt/project/maven/hello-world/target
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/main/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/classes
[INFO] 
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/test/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/test-classes
[INFO] 
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ hello-world ---
[INFO] Surefire report directory: /opt/project/maven/hello-world/target/surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.juvenxu.mvnbook.helloworld.HelloWorldTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.142 sec

Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

[INFO] 
[INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ hello-world ---
[INFO] Building jar: /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT.jar
[INFO] 
[INFO] --- maven-shade-plugin:1.2.1:shade (default) @ hello-world ---
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm/3.1/asm-3.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm/3.1/asm-3.1.pom (278 B at 515 B/s)
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm-parent/3.1/asm-parent-3.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm-parent/3.1/asm-parent-3.1.pom (4.2 kB at 8.4 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm-commons/3.1/asm-commons-3.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm-commons/3.1/asm-commons-3.1.pom (436 B at 807 B/s)
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm-tree/3.1/asm-tree-3.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm-tree/3.1/asm-tree-3.1.pom (425 B at 863 B/s)
Downloading from central: https://repo.maven.apache.org/maven2/jdom/jdom/1.0/jdom-1.0.pom
Downloaded from central: https://repo.maven.apache.org/maven2/jdom/jdom/1.0/jdom-1.0.pom (1.2 kB at 2.2 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/shared/maven-dependency-tree/1.1/maven-dependency-tree-1.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/shared/maven-dependency-tree/1.1/maven-dependency-tree-1.1.pom (2.9 kB at 5.2 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/shared/maven-shared-components/8/maven-shared-components-8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/shared/maven-shared-components/8/maven-shared-components-8.pom (2.7 kB at 4.7 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-parent/7/maven-parent-7.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-parent/7/maven-parent-7.pom (21 kB at 31 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-project/2.0.8/maven-project-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-project/2.0.8/maven-project-2.0.8.pom (2.7 kB at 4.8 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven/2.0.8/maven-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven/2.0.8/maven-2.0.8.pom (12 kB at 19 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-parent/6/maven-parent-6.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-parent/6/maven-parent-6.pom (20 kB at 28 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-settings/2.0.8/maven-settings-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-settings/2.0.8/maven-settings-2.0.8.pom (2.1 kB at 3.5 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-model/2.0.8/maven-model-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-model/2.0.8/maven-model-2.0.8.pom (3.1 kB at 5.5 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/codehaus/plexus/plexus-utils/1.4.6/plexus-utils-1.4.6.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/codehaus/plexus/plexus-utils/1.4.6/plexus-utils-1.4.6.pom (2.3 kB at 4.0 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-profile/2.0.8/maven-profile-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-profile/2.0.8/maven-profile-2.0.8.pom (2.0 kB at 4.2 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-artifact-manager/2.0.8/maven-artifact-manager-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-artifact-manager/2.0.8/maven-artifact-manager-2.0.8.pom (2.7 kB at 5.3 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-repository-metadata/2.0.8/maven-repository-metadata-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-repository-metadata/2.0.8/maven-repository-metadata-2.0.8.pom (1.9 kB at 4.3 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-artifact/2.0.8/maven-artifact-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-artifact/2.0.8/maven-artifact-2.0.8.pom (1.6 kB at 2.8 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-plugin-registry/2.0.8/maven-plugin-registry-2.0.8.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/maven-plugin-registry/2.0.8/maven-plugin-registry-2.0.8.pom (2.0 kB at 4.2 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/codehaus/plexus/plexus-utils/1.5.5/plexus-utils-1.5.5.jar
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm/3.1/asm-3.1.jar
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm-commons/3.1/asm-commons-3.1.jar
Downloading from central: https://repo.maven.apache.org/maven2/asm/asm-tree/3.1/asm-tree-3.1.jar
Downloading from central: https://repo.maven.apache.org/maven2/jdom/jdom/1.0/jdom-1.0.jar
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm/3.1/asm-3.1.jar (43 kB at 38 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/shared/maven-dependency-tree/1.1/maven-dependency-tree-1.1.jar
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm-tree/3.1/asm-tree-3.1.jar (22 kB at 13 kB/s)
Downloaded from central: https://repo.maven.apache.org/maven2/asm/asm-commons/3.1/asm-commons-3.1.jar (33 kB at 14 kB/s)
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/shared/maven-dependency-tree/1.1/maven-dependency-tree-1.1.jar (34 kB at 15 kB/s)
Downloaded from central: https://repo.maven.apache.org/maven2/jdom/jdom/1.0/jdom-1.0.jar (153 kB at 57 kB/s)
Downloaded from central: https://repo.maven.apache.org/maven2/org/codehaus/plexus/plexus-utils/1.5.5/plexus-utils-1.5.5.jar (251 kB at 75 kB/s)
[INFO] Replacing original artifact with shaded artifact.
[INFO] Replacing /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT.jar with /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT-shaded.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 25.081 s
[INFO] Finished at: 2018-06-13T05:45:01+08:00
[INFO] ------------------------------------------------------------------------

我们还需要一个安装的步骤，执行 mvn clean install：

[root@wangmaster hello-world]# mvn clean install
[INFO] Scanning for projects...
[INFO] 
[INFO] ------------------< com.juvenxu.mvnbook:hello-world >-------------------
[INFO] Building Maven Hello World Project 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
[INFO] 
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ hello-world ---
[INFO] Deleting /opt/project/maven/hello-world/target
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/main/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/classes
[INFO] 
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ hello-world ---
[WARNING] Using platform encoding (UTF-8 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory /opt/project/maven/hello-world/src/test/resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ hello-world ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding UTF-8, i.e. build is platform dependent!
[INFO] Compiling 1 source file to /opt/project/maven/hello-world/target/test-classes
[INFO] 
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ hello-world ---
[INFO] Surefire report directory: /opt/project/maven/hello-world/target/surefire-reports

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.juvenxu.mvnbook.helloworld.HelloWorldTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.171 sec

Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

[INFO] 
[INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ hello-world ---
[INFO] Building jar: /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT.jar
[INFO] 
[INFO] --- maven-shade-plugin:1.2.1:shade (default) @ hello-world ---
[INFO] Replacing original artifact with shaded artifact.
[INFO] Replacing /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT.jar with /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT-shaded.jar
[INFO] 
[INFO] --- maven-install-plugin:2.4:install (default-install) @ hello-world ---
[INFO] Installing /opt/project/maven/hello-world/target/hello-world-1.0-SNAPSHOT.jar to /root/.m2/repository/com/juvenxu/mvnbook/hello-world/1.0-SNAPSHOT/hello-world-1.0-SNAPSHOT.jar
[INFO] Installing /opt/project/maven/hello-world/pom.xml to /root/.m2/repository/com/juvenxu/mvnbook/hello-world/1.0-SNAPSHOT/hello-world-1.0-SNAPSHOT.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 5.932 s
[INFO] Finished at: 2018-06-13T05:45:13+08:00
[INFO] ------------------------------------------------------------------------

现在，我们在项目根目录中执行该jar文件：

[root@wangmaster hello-world]# java -jar target/hello-world-1.0-SNAPSHOT.jar 
Hello Maven

参考文章：https://blog.csdn.net/u010523770/article/details/70168353