eclipse Maven - 为什么在“mvn clean”之后我需要在“mvn package”之前执行“Maven Update Project”？
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时间：2020-09-10 21:37:34 来源:igfitidea点击:
Maven - Why after "mvn clean" I need to execute "Maven Update Project" before "mvn package"?
提问by Pmt
I'm making some tests and I would like to understand why after execute the command mvn cleanI need to execute "Maven > Update Project" before run mvn package, otherwise I get a compilation error in one of my dependencies during the packaging.
我正在做一些测试，我想了解为什么在执行命令后mvn clean我需要在 run 之前执行“Maven > Update Project” mvn package，否则在打包过程中我的依赖项之一出现编译错误。
It looks like my project doesn't compile correctly my project before running "Maven > Update Project", but I'm not sure. Is this normal?
看起来我的项目在运行“Maven > Update Project”之前没有正确编译我的项目，但我不确定。这是正常的吗？
- I'm using Eclipse and run the commands {mvn clean} and {mvn package} via "Run as > Maven Build".
- 我正在使用 Eclipse 并通过“Run as > Maven Build”运行命令 {mvn clean} 和 {mvn package}。
Here is my pom.xml:
这是我的 pom.xml：
<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>com.project</groupId>
<artifactId>myProject</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
<jmockit.version>0.0.1</jmockit.version>
</properties>
<build>
<testSourceDirectory>src/test/java/junit</testSourceDirectory>
<resources>
<resource>
<directory>src/main/java</directory>
<excludes>
<exclude>**/*.java</exclude>
</excludes>
</resource>
</resources>
<testResources>
<testResource>
<directory>src/test/java/selenium</directory>
<excludes>
<exclude>**/*.java</exclude>
</excludes>
</testResource>
</testResources>
<pluginManagement>
<plugins>
<!-- Need Java 5, which is the default since v2.3 of the maven-compiler-plugin. -->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.5.1</version>
</plugin>
</plugins>
</pluginManagement>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.2</version>
<configuration>
<failOnMissingWebXml>false</failOnMissingWebXml>
<warSourceExcludes>src/main/resources/conf_development</warSourceExcludes>
<webResources>
<resource>
<directory>src/main/resources/conf_production</directory>
<targetPath>WEB-INF/classes/</targetPath>
<includes>
<include>**/*</include>
</includes>
</resource>
<resource>
<directory>src/main/resources/conf</directory>
<targetPath>WEB-INF/classes/</targetPath>
<includes>
<include>**/*</include>
</includes>
</resource>
</webResources>
</configuration>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<argLine>
-javaagent:"${settings.localRepository}"/mockit/jmockit/${jmockit.version}/jmockit-${jmockit.version}.jar
</argLine>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>asm</groupId>
<artifactId>asm</artifactId>
<version>1.5.3</version>
</dependency>
<dependency>
<groupId>bouncycastle</groupId>
<artifactId>bcprov-jdk14</artifactId>
<version>140</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0-oracle-thin-extras</artifactId>
<version>0.9.0.2</version>
</dependency>
<dependency>
<groupId>commons-betwixt</groupId>
<artifactId>commons-betwixt</artifactId>
<version>0.7</version>
</dependency>
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-email</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache-core</artifactId>
<version>2.4.2</version>
</dependency>
<dependency>
<groupId>com.googlecode.ehcache-spring-annotations</groupId>
<artifactId>ehcache-spring-annotations</artifactId>
<version>1.1.3</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-annotations</artifactId>
<version>3.4.0.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>3.4.0.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>3.3.2.GA</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.1.2</version>
</dependency>
<dependency>
<groupId>net.sf.json-lib</groupId>
<artifactId>json-lib</artifactId>
<version>2.4</version>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>2.5.6</version>
</dependency>
<dependency>
<groupId>net.fckeditor</groupId>
<artifactId>java-core</artifactId>
<version>2.4</version>
</dependency>
<dependency>
<groupId>backport-util-concurrent</groupId>
<artifactId>backport-util-concurrent</artifactId>
<version>3.1</version>
</dependency>
<dependency>
<groupId>com.oracle</groupId>
<artifactId>ojdbc14</artifactId>
<version>10.2.0.1.0</version>
</dependency>
<dependency>
<groupId>com.ibm.icu</groupId>
<artifactId>icu4j</artifactId>
<version>3.8</version>
</dependency>
<dependency>
<groupId>mockit</groupId>
<artifactId>jmockit</artifactId>
<version>${jmockit.version}</version>
</dependency>
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>2.0</version>
</dependency>
<dependency>
<groupId>com.lowagie</groupId>
<artifactId>itext</artifactId>
<version>2.1.0</version>
</dependency>
<dependency>
<groupId>atg.taglib.json</groupId>
<artifactId>json-taglib</artifactId>
<version>0.4.1</version>
</dependency>
<dependency>
<groupId>commons-httpclient</groupId>
<artifactId>commons-httpclient</artifactId>
<version>3.1</version>
</dependency>
<dependency>
<groupId>net.sourceforge.jexcelapi</groupId>
<artifactId>jxl</artifactId>
<version>2.6</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<dependency>
<groupId>org.mockito</groupId>
<artifactId>mockito-all</artifactId>
<version>1.8.5</version>
</dependency>
<dependency>
<groupId>org.quartz-scheduler</groupId>
<artifactId>quartz</artifactId>
<version>1.8.4</version>
</dependency>
<dependency>
<groupId>org.seleniumhq.selenium</groupId>
<artifactId>selenium-server</artifactId>
<version>2.25.0</version>
<type>pom</type>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring</artifactId>
<version>2.5.6.SEC03</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-agent</artifactId>
<version>2.5.6.SEC03</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>2.5.6.SEC03</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-config-browser-plugin</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-convention-plugin</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-core</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-jasperreports-plugin</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-jfreechart-plugin</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-json-plugin</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-spring-plugin</artifactId>
<version>2.2.1</version>
</dependency>
<dependency>
<groupId>org.apache.velocity</groupId>
<artifactId>velocity</artifactId>
<version>1.6.3</version>
</dependency>
<dependency>
<groupId>org.apache.velocity</groupId>
<artifactId>velocity-tools</artifactId>
<version>1.3</version>
</dependency>
<dependency>
<groupId>com.yahoo.platform.yui</groupId>
<artifactId>yuicompressor</artifactId>
<version>2.4.6</version>
</dependency>
<dependency>
<groupId>commons-lang</groupId>
<artifactId>commons-lang</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>net.sf.jodreports</groupId>
<artifactId>jodreports</artifactId>
<version>2.4.0</version>
</dependency>
<dependency>
<groupId>org.springframework.ws</groupId>
<artifactId>spring-oxm</artifactId>
<version>1.5.9</version>
</dependency>
<dependency>
<groupId>org.springframework.ws</groupId>
<artifactId>spring-ws-core</artifactId>
<version>1.5.9</version>
</dependency>
<dependency>
<groupId>org.springframework.ws</groupId>
<artifactId>spring-oxm-tiger</artifactId>
<version>1.5.9</version>
</dependency>
<dependency>
<groupId>org.springframework.ws</groupId>
<artifactId>spring-ws-core-tiger</artifactId>
<version>1.5.9</version>
</dependency>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.1</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-xjc</artifactId>
<version>2.1</version>
</dependency>
<dependency>
<groupId>org.apache.ws.commons.axiom
</groupId>
<artifactId>axiom-api</artifactId>
<version>1.2.5</version>
</dependency>
<dependency>
<groupId>org.apache.ws.commons.axiom
</groupId>
<artifactId>axiom-impl</artifactId>
<version>1.2.5</version>
</dependency>
<dependency>
<groupId>javax.xml</groupId>
<artifactId>jaxrpc-api</artifactId>
<version>1.1</version>
</dependency>
<dependency>
<groupId>org.seleniumhq.selenium.client-drivers</groupId>
<artifactId>selenium-java-client-driver</artifactId>
<version>1.0.1</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
</dependency>
<dependency>
<groupId>org.acegisecurity</groupId>
<artifactId>acegi-security</artifactId>
<version>1.0.7</version>
</dependency>
<dependency>
<groupId>citizen</groupId>
<artifactId>citizen</artifactId>
<version>citizen</version>
</dependency>
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.4</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>jasperreports</groupId>
<artifactId>jasperreports</artifactId>
<version>3.5.3</version>
</dependency>
</dependencies>
</project>
The error:
错误：
(Remembering that the lib with error it's an internal lib and it work just fine after "Maven > Update Project")
（记住，有错误的库是内部库，在“Maven > 更新项目”之后它工作得很好）
[INFO] Compiling 2595 source files to C:\Users\user\Documents\Dev\workspace\project\target\classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] C:\Users\user\Documents\Dev\workspace\project\src\main\java\com\project\jobs\citizen\model\service\CitizenService.java:[38
,34] cannot access org.apache.axis.client.Service
class file for org.apache.axis.client.Service not found
Resolution2Locator r2 = new Resolution2Locator ();
[INFO] 1 error
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2:09.448s
[INFO] Finished at: Fri Mar 22 11:55:14 BRT 2013
[INFO] Final Memory: 25M/274M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.5.1:compile (default-compile) on project project: Compilation failure
[ERROR] C:\Users\user\Documents\Dev\workspace\project
\src\main\java\com\project\jobs\citizen\model\service\CitizenService.java:[38
,34] cannot access org.apache.axis.client.Service
[ERROR] class file for org.apache.axis.client.Service not found
[ERROR] Resolution2Locator r2 = new Resolution2Locator();
[ERROR] -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.5.1:compile (default-compile) on project u
nico: Compilation failure
C:\Users\user\Documents\Dev\workspace\project\src\main\java\com\project\jobs\citizen\model\service\CitizenService.java:[38,34] can
not access org.apache.axis.client.Service
class file for org.apache.axis.client.Service not found
Resolution2Locator r2 = new Resolution2Locator ();
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:213)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)
Caused by: org.apache.maven.plugin.CompilationFailureException: Compilation failure
C:\Users\user\Documents\Dev\workspace\project\src\main\java\com\project\jobs\citizen\model\service\CitizenService.java:[38,34] can
not access org.apache.axis.client.Service
class file for org.apache.axis.client.Service not found
Resolution2Locator r2 = new Resolution2Locator ();
at org.apache.maven.plugin.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:729)
at org.apache.maven.plugin.CompilerMojo.execute(CompilerMojo.java:128)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
... 19 more
[ERROR]
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
回答by dmiandre
Here is what happens:
这是发生的事情：
mvn cleandeletes thetargetdirectorymvn packageperforms some work, but then encounters a compilation error due to a missing dependency. That's why the target folder is in error.- Running Maven > Update Project in Eclipse causes Eclipse to perform its own compilation, separate from Maven. Eclipse has a different classpath than Maven, so its compilation succeeds. Now the
targetdirectory has all the compiled classes. - Re-running
mvn packagenow succeeds, because it finds all the classes already compiled and doesn't need to perform any compilation.
mvn clean删除target目录mvn package执行一些工作，但随后由于缺少依赖项而遇到编译错误。这就是目标文件夹出错的原因。- 在 Eclipse 中运行 Maven > Update Project 会导致 Eclipse 执行自己的编译，独立于 Maven。Eclipse 具有与 Maven 不同的类路径，因此其编译成功。现在该
target目录包含所有已编译的类。 mvn package现在重新运行成功，因为它找到了所有已经编译的类，不需要执行任何编译。
Ultimately, the problem is in the project configuration in pom.xml. I had the same problem, and after adding the missing dependency I successfully compiled project with Maven.
最终，问题出在pom.xml. 我遇到了同样的问题，在添加了缺少的依赖项后，我成功地用 Maven 编译了项目。
回答by Nathaniel Waisbrot
The Eclipse m2e plugin (this is a simplification) reads the POM file and translates it into instructions for Eclipse so that Eclipse can do its thing. Because Eclipse is in control the whole time, your view gets updated correctly and things are pretty smooth. Some more advanced Maven actions with plugins are not supported by m2e, and so those actions just won't happen. Some simple stuff, like the classpath is different from how Maven does things -- m2e uses the "test" classpath no matter what because Eclipse can't predict what you'll want to run.
Eclipse m2e 插件（这是一个简化）读取 POM 文件并将其转换为 Eclipse 的指令，以便 Eclipse 可以完成它的工作。因为 Eclipse 一直处于控制之中，所以您的视图会正确更新并且事情非常顺利。m2e 不支持一些带有插件的更高级的 Maven 操作，因此这些操作不会发生。一些简单的东西，比如类路径与 Maven 的工作方式不同——m2e 无论如何都使用“测试”类路径，因为 Eclipse 无法预测您想要运行的内容。
On the other hand, performing "Run as > Maven ..." actually calls Maven, a program completely outside of Eclipse, and asks it to run. Eclipse doesn't automatically know when files have been created or deleted by Maven.
另一方面，执行“Run as > Maven ...”实际上会调用 Maven，这是一个完全在 Eclipse 之外的程序，并要求它运行。Eclipse 不会自动知道 Maven 何时创建或删除了文件。
I would generally stay away from the "Run as > Maven" commands. The integration is poor, the Eclipse console interface is ugly, it's just easier to call mvnfrom the command line if you need to run specific Maven goals.
我通常会远离“Run as > Maven”命令。集成很差，Eclipse 控制台界面很难看，mvn如果您需要运行特定的 Maven 目标，从命令行调用会更容易。
If you just want to develop a Maven project, I find the m2e integration works very well. I use Jenkins to handle the packaging and deployment for me, so I'm only using Eclipse to edit and test my code.
如果你只是想开发一个 Maven 项目，我发现 m2e 集成效果很好。我使用 Jenkins 为我处理打包和部署，所以我只使用 Eclipse 来编辑和测试我的代码。
回答by PSR
It will update the files if any new updates avialable.you can use maven install after maven clean
如果有任何新的更新可用，它将更新文件。您可以在 maven clean 后使用 maven install
