linux安裝maven

先解壓maven的壓縮包apache-maven-3.5.4-bin.tar.gz   命令: tar -zavf pache-maven-3.5.4-bin.tar.gz

然後編輯linux的環境變數屬性:vim etc/profile

在末尾新增如下程式碼

export M2_HOME=/home/maven/apache-maven-3.5.4   //你maven的解壓目錄

export path=$M2_HOME/bin:

配置中央倉庫的映象:(因為國內訪問阿里的網站快一些,換成了阿里的)

 vim /home/maven/apache-maven-3.5.4/conf/settings.xml 

在<mirrors>標籤下加入倉庫配置的資訊

<mirror> 　　<id>alimaven</id> 　　<name>aliyun maven</name> 　　<url>http://maven.aliyun.com/nexus/content/groups/public/</url> 　　<mirrorOf>central</mirrorOf> </mirror>

在Linux搭建Nexus私服

ftp把nexus-2.14.0-01-bundle.tar.gz壓縮包上傳到Linux中

tar -zxvf nexus-2.14.0-01-bundle.tar.gz解壓出現兩個資料夾

　　nexus-2.14.0-01 主要用到這個資料夾

　　sonatype-work 儲存所有配置檔案的資訊(不用動)

啟動nexus

　　進入 cd /home/nexus/nexus-2.14.0-01/bin/nexus  

　　./nexus start

啟動後 預設埠8081可以去訪問 http://192.168.1.105:8081/nexus/

將所有proxy中的下載配置開啟(右鍵 proxy 選擇Repair index)

Public Repositories 對應的地址 http://192.168.1.105:8081/nexus/content/groups/public/  我們的倉庫地址

最後: 在setting.xml配置私服的引用(是我們開發環境 maven的setting.xml檔案)

<?xml version="1.0" encoding="UTF-8"?>

<!--
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<!--
 | This is the configuration file for Maven. It can be specified at two levels:
 |
 |  1. User Level. This settings.xml file provides configuration for a single user,
 |                 and is normally provided in ${user.home}/.m2/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -s /path/to/user/settings.xml
 |
 |  2. Global Level. This settings.xml file provides configuration for all Maven
 |                 users on a machine (assuming they're all using the same Maven
 |                 installation). It's normally provided in
 |                 ${maven.conf}/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -gs /path/to/global/settings.xml
 |
 | The sections in this sample file are intended to give you a running start at
 | getting the most out of your Maven installation. Where appropriate, the default
 | values (values used when the setting is not specified) are provided.
 |
 |-->
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
  <!-- localRepository
   | The path to the local repository maven will use to store artifacts.
   |
   | Default: ${user.home}/.m2/repository
  <localRepository>/path/to/local/repo</localRepository>
  -->

  <!-- interactiveMode
   | This will determine whether maven prompts you when it needs input. If set to false,
   | maven will use a sensible default value, perhaps based on some other setting, for
   | the parameter in question.
   |
   | Default: true
  <interactiveMode>true</interactiveMode>
  -->

  <!-- offline
   | Determines whether maven should attempt to connect to the network when executing a build.
   | This will have an effect on artifact downloads, artifact deployment, and others.
   |
   | Default: false
  <offline>false</offline>
  -->

  <!-- pluginGroups
   | This is a list of additional group identifiers that will be searched when resolving plugins by their prefix, i.e.
   | when invoking a command line like "mvn prefix:goal". Maven will automatically add the group identifiers
   | "org.apache.maven.plugins" and "org.codehaus.mojo" if these are not already contained in the list.
   |-->
  <pluginGroups>
    <!-- pluginGroup
     | Specifies a further group identifier to use for plugin lookup.
    <pluginGroup>com.your.plugins</pluginGroup>
    -->
  </pluginGroups>

  <!-- proxies
   | This is a list of proxies which can be used on this machine to connect to the network.
   | Unless otherwise specified (by system property or command-line switch), the first proxy
   | specification in this list marked as active will be used.
   |-->
  <proxies>
    <!-- proxy
     | Specification for one proxy, to be used in connecting to the network.
     |
    <proxy>
      <id>optional</id>
      <active>true</active>
      <protocol>http</protocol>
      <username>proxyuser</username>
      <password>proxypass</password>
      <host>proxy.host.net</host>
      <port>80</port>
      <nonProxyHosts>local.net|some.host.com</nonProxyHosts>
    </proxy>
    -->
  </proxies>

  <!-- servers
   | This is a list of authentication profiles, keyed by the server-id used within the system.
   | Authentication profiles can be used whenever maven must make a connection to a remote server.
   |-->
  <servers>
    <!-- server
     | Specifies the authentication information to use when connecting to a particular server, identified by
     | a unique name within the system (referred to by the 'id' attribute below).
     |
     | NOTE: You should either specify username/password OR privateKey/passphrase, since these pairings are
     |       used together.
     |
    <server>
      <id>deploymentRepo</id>
      <username>repouser</username>
      <password>repopwd</password>
    </server>
    -->

    <!-- Another sample, using keys to authenticate.
    <server>
      <id>siteServer</id>
      <privateKey>/path/to/private/key</privateKey>
      <passphrase>optional; leave empty if not used.</passphrase>
    </server>
    -->
    <server>
        <id>nexus-releases</id>
        <username>admin</username>
        <password>admin123</password>
    </server>
    <server>
        <id>nexus-snapshots</id>
        <username>admin</username>
        <password>admin123</password>
    </server>
  </servers>

  <!-- mirrors
   | This is a list of mirrors to be used in downloading artifacts from remote repositories.
   |
   | It works like this: a POM may declare a repository to use in resolving certain artifacts.
   | However, this repository may have problems with heavy traffic at times, so people have mirrored
   | it to several places.
   |
   | That repository definition will have a unique id, so we can create a mirror reference for that
   | repository, to be used as an alternate download site. The mirror site will be the preferred
   | server for that repository.
   |-->
  <mirrors>
    <!--<mirror>
          <id>alimaven</id>
          <name>aliyun maven</name>
          <url>http://maven.aliyun.com/nexus/content/groups/public/</url>
          <mirrorOf>central</mirrorOf>        
    </mirror>
    -->
    <mirror>
        <id>nexus-releases</id>
        <url>http://119.23.50.194:8081/nexus/content/groups/public/</url>
        <mirrorOf>*</mirrorOf>        
    </mirror>
    <mirror>
        <id>nexus-snapshots</id>
        <url>http://119.23.50.194:8081/nexus/content/groups/public//</url>
        <mirrorOf>*</mirrorOf>        
    </mirror>
    <!-- mirror
     | Specifies a repository mirror site to use instead of a given repository. The repository that
     | this mirror serves has an ID that matches the mirrorOf element of this mirror. IDs are used
     | for inheritance and direct lookup purposes, and must be unique across the set of mirrors.
     |
    <mirror>
      <id>mirrorId</id>
      <mirrorOf>repositoryId</mirrorOf>
      <name>Human Readable Name for this Mirror.</name>
      <url>http://my.repository.com/repo/path</url>
    </mirror>
     -->
  </mirrors>

  <!-- profiles
   | This is a list of profiles which can be activated in a variety of ways, and which can modify
   | the build process. Profiles provided in the settings.xml are intended to provide local machine-
   | specific paths and repository locations which allow the build to work in the local environment.
   |
   | For example, if you have an integration testing plugin - like cactus - that needs to know where
   | your Tomcat instance is installed, you can provide a variable here such that the variable is
   | dereferenced during the build process to configure the cactus plugin.
   |
   | As noted above, profiles can be activated in a variety of ways. One way - the activeProfiles
   | section of this document (settings.xml) - will be discussed later. Another way essentially
   | relies on the detection of a system property, either matching a particular value for the property,
   | or merely testing its existence. Profiles can also be activated by JDK version prefix, where a
   | value of '1.4' might activate a profile when the build is executed on a JDK version of '1.4.2_07'.
   | Finally, the list of active profiles can be specified directly from the command line.
   |
   | NOTE: For profiles defined in the settings.xml, you are restricted to specifying only artifact
   |       repositories, plugin repositories, and free-form properties to be used as configuration
   |       variables for plugins in the POM.
   |
   |-->
  <profiles>
    <!-- profile
     | Specifies a set of introductions to the build process, to be activated using one or more of the
     | mechanisms described above. For inheritance purposes, and to activate profiles via <activatedProfiles/>
     | or the command line, profiles have to have an ID that is unique.
     |
     | An encouraged best practice for profile identification is to use a consistent naming convention
     | for profiles, such as 'env-dev', 'env-test', 'env-production', 'user-jdcasey', 'user-brett', etc.
     | This will make it more intuitive to understand what the set of introduced profiles is attempting
     | to accomplish, particularly when you only have a list of profile id's for debug.
     |
     | This profile example uses the JDK version to trigger activation, and provides a JDK-specific repo.
    <profile>
      <id>jdk-1.4</id>

      <activation>
        <jdk>1.4</jdk>
      </activation>

      <repositories>
        <repository>
          <id>jdk14</id>
          <name>Repository for JDK 1.4 builds</name>
          <url>http://www.myhost.com/maven/jdk14</url>
          <layout>default</layout>
          <snapshotPolicy>always</snapshotPolicy>
        </repository>
      </repositories>
    </profile>
    -->

    <!--
     | Here is another profile, activated by the system property 'target-env' with a value of 'dev',
     | which provides a specific path to the Tomcat instance. To use this, your plugin configuration
     | might hypothetically look like:
     |
     | ...
     | <plugin>
     |   <groupId>org.myco.myplugins</groupId>
     |   <artifactId>myplugin</artifactId>
     |
     |   <configuration>
     |     <tomcatLocation>${tomcatPath}</tomcatLocation>
     |   </configuration>
     | </plugin>
     | ...
     |
     | NOTE: If you just wanted to inject this configuration whenever someone set 'target-env' to
     |       anything, you could just leave off the <value/> inside the activation-property.
     |
    <profile>
      <id>env-dev</id>

      <activation>
        <property>
          <name>target-env</name>
          <value>dev</value>
        </property>
      </activation>

      <properties>
        <tomcatPath>/path/to/tomcat/instance</tomcatPath>
      </properties>
    </profile>
    -->
    <profiles>
       <profile>
          <id>env-dev</id>
          <repositories>
            <repository>
              <id>public</id>
              <name>Public Repositories</name>
              <url>http://119.23.50.194:8081/nexus/content/groups/public/</url>
              <layout>default</layout>
              <snapshotPolicy>true</snapshotPolicy>
            </repository>
          </repositories>
        </profile>
    </profiles>
    <activeProfiles>
        <activeProfile>env-dev</activeProfile>
    </activeProfiles>
  <!-- activeProfiles
   | List of profiles that are active for all builds.
   |
  <activeProfiles>
    <activeProfile>alwaysActiveProfile</activeProfile>
    <activeProfile>anotherAlwaysActiveProfile</activeProfile>
  </activeProfiles>
  -->
</settings>

如果新增其他的jar包時，會先在nexus私服下載好，以後才會下載到本地。以後，如果發現私服已經存在某一jar包，則會直接從私服下載，如果沒有再去網路上下載。

上傳自定義jar包到私服

在需要上傳的工程中的pom.xml檔案中加入下面的配置

需要保證上面settings.xml中配置已經通過server標籤配置了鑑權賬號  這裡repository的<id>nexus-releases</id>要 與上面setting.xml檔案中server標籤的id元素相匹配。

	<distributionManagement>
		<repository>
			<id>nexus-releases</id>
			<name>Nexus Release Repository</name>
			<url>http://192.168.1.105:8081/nexus/content/repositories/releases/</url>
		</repository>
		<snapshotRepository>
			<id>nexus-snapshots</id>
			<name>Nexus Snapshot Repository</name>
			<url>http://192.168.1.105:8081/nexus/content/repositories/snapshots/</url>
		</snapshotRepository>
	</distributionManagement>

上傳命令：

mvn deploy:deploy-file -DgroupId=groupId -DartifactId=artifactId -Dversion=version -Dfile=本地jar包路徑 -DrepositoryId=releases/snapshots -Durl=倉庫地址

舉例：上傳jmxri-1.2.1.jar，本地存放在D盤

mvn deploy:deploy-file -DgroupId=com.sun.jmx –DartifactId=jmxri -Dversion=1.2.1 -Dfile=d:/jmxri-1.2.1.jar -DrepositoryId=releases -Durl=http://ip/nexus/content/repositories/releases

依賴包的管理

問題引入：

　　Web專案開發的時候往往都會將所有的開發程式打包成一個*.war檔案。那麼在這個war檔案裡面就會存在有lib目錄儲存所有的第三方程式開發包檔案

　　對於一些重要的開發包，那就需要將其進行儲存，如果不需要的開發包，那麼就不希望其輸出到lib之中。

　　列如:Junit 往往只做測試使用，而實際專案釋出的時候，這個開發包就沒有任何的用處，所以就不希望其可以自動的輸出到war檔案中去

解決辦法：

　　<scope>****</scope> 就屬於開發包的作用域，junit屬於測試環境下的 所以使用test作用域。

　　如果作用域沒有任何配置指的就是compile，輸出到lib檔案的只有compile範圍的開發包

　　如果scope設為 provided。說明該程式包的實現將依賴我們的容器完成，如servlet開發包本身都會由Tomcat容器提供。

　　所以這個包只在編譯專案的時候有效，那麼本質上也沒有必要儲存到lib目錄下。

依賴包的排除

　　當我們的A專案去依賴B包的時候，發現B包又依賴C包，但是我們配置之中又發現專案A也要去引用C依賴包。這樣一來 就有可能造成包的衝突，

　　所以就不希望B欄位依賴的C包加入到專案的編譯裡面來，這樣就需要一個包的排除處理。

實現包的排除

<dependency>
 <exclusions>
     <exclusion>
             <groupId>****</groupId>
            <artifactId>A</artifactId>
     </exclusion>
 </exclusions>
</dependency>

這樣我們的Ajar包就不會通過依賴釋出到war檔案

繼承關係

通過配置<parent></parent>相關的屬性以及配置的外掛(JDK外掛，tomcat外掛等)和屬性都會自動通過父專案繼承而來

  <parent>
    <groupId>****</groupId>
    <artifactId>*</artifactId>
    <version>***</version>
  </parent>

對於子專案而言，也需要繼續匯入開發包，與之前最大的區別是不需要處理版本號。