Maven路上的疑难杂症

问题一：idea同步jar包提示“Could not find artifact org.springframework.security.oauth.boot:spring-security-oauth2-autoconfigure:pom:2.1.0.M4 in aliyunmaven”错误；

问题二：本地有maven依赖，idea却扫描不到；

问题三：配置阿里云镜像，但是同步依赖报错；

问题四：Maven的pom.xml文件灰色画横线；

问题一：idea同步jar包报错

方法一：使用镜像仓库同步一遍（加速），然后再使用中央仓库同步一遍（下载未找到的依赖包）；
注意：勾选上“File > settings > Build, Execution, Deployment > Build Tools : Maven”下的Always update snapshots勾选上，表示idea扫描maven时优先从本地扫描；
注意：若是没有解决，则需要删除本地maven仓库下对应依赖的文件夹中的_remote.repositories文件再重启idea，同时还需要删除文件夹下的.lastUpdated文件；
作用：通过删除仓库中的_remote.repositories文件,解决由于更换仓库带来的jar包不兼容/重新下载问题；

方法二：复制别人的Maven本地仓库，将本地maven仓库下对应依赖的文件夹中的_remote.repositories文件再重启idea，同时还需要删除文件夹下的.lastUpdated文件；

问题二：idea扫描不到本地maven仓库

方法一：勾选上idea中maven设置的Work offline，开启maven的离线模式；

问题三：配置阿里云镜像，但是同步依赖报错；

方式一：关闭idea中maven的离线模式（取消勾选idea中maven设置的Work offline）；
方法二：找到maven同步窗口，点击报错项Dependency Resolution Failed，然后点击右侧提示Switch Off Offline Mode即可关闭idea中maven的离线模式；

注意：本人idea版本为2021.2.2版本，不同版本可能选项有所区别；

问题四：Maven的pom.xml文件灰色画横线；

解决方法：在idea的maven设置中的ignored Files设置中取消勾选对应的pox.xml文件。路径为：File -> Settings -> Build, ... -> Build Tools -> Maven -> igored Files

maven 3.6.3 配置

配置本地仓库

  <!-- 本地仓库 --><localRepository>D:\Software\Repository\Maven</localRepository>

配置远程镜像仓库

    <!-- 远程镜像仓库 --><mirror><id>aliyunmaven</id><mirrorOf>*</mirrorOf><name>阿里云公共仓库</name><url>https://maven.aliyun.com/repository/public</url></mirror></mirrors>

配置Java版本

    <!-- java1.8版本 --> <profile><id>jdk-1.8</id><activation><activeByDefault>true</activeByDefault><jdk>1.8</jdk></activation><properties><maven.compiler.source>1.8</maven.compiler.source><maven.compiler.target>1.8</maven.compiler.target><maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion></properties></profile>

完整配置文件

<?xml version="1.0" encoding="UTF-8"?><!--
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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>--><!-- 本地仓库 --><localRepository>D:\Software\Repository\Maven</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>--></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| 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>--><!-- 远程镜像仓库 --><mirror><id>aliyunmaven</id><mirrorOf>*</mirrorOf><name>阿里云公共仓库</name><url>https://maven.aliyun.com/repository/public</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>--><!-- java1.8版本 --> <profile><id>jdk-1.8</id><activation><activeByDefault>true</activeByDefault><jdk>1.8</jdk></activation><properties><maven.compiler.source>1.8</maven.compiler.source><maven.compiler.target>1.8</maven.compiler.target><maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion></properties></profile></profiles><!-- activeProfiles| List of profiles that are active for all builds.|<activeProfiles><activeProfile>alwaysActiveProfile</activeProfile><activeProfile>anotherAlwaysActiveProfile</activeProfile></activeProfiles>-->
</settings>