我已经尝试了这里找到的所有可能的解决方案，包括：
- find ~/.m2 -name "*.lastUpdated" -exec grep -q "Could not transfer" {} \; -print -exec rm {} \;
- mvn -U 清洁
反正也不行，具体日志如下：
顺便说一句：我试图从mkyong 站点运行 struts2 示例代码
[DEBUG] =======================================================================
[DEBUG] com.mkyong.common:Struts2Example:war:com.mkyong.common
[DEBUG] junit:junit:jar:3.8.1:test
[DEBUG] org.apache.struts:struts2-core:jar:2.1.8:compile
[DEBUG] com.opensymphony:xwork-core:jar:2.1.6:compile
[DEBUG] org.springframework:spring-test:jar:2.5.6:compile
[DEBUG] commons-logging:commons-logging:jar:1.1.1:compile
[DEBUG] org.freemarker:freemarker:jar:2.3.15:compile
[DEBUG] ognl:ognl:jar:2.7.3:compile
[DEBUG] commons-fileupload:commons-fileupload:jar:1.2.1:compile
[DEBUG] commons-io:commons-io:jar:1.3.2:compile
[DEBUG] com.sun:tools:jar:1.5.0:system
[DEBUG] org.apache.struts:struts2-convention-plugin:jar:2.1.8:compile
[DEBUG] Using connector WagonRepositoryConnector with priority 0 for http://repo
.maven.apache.org/maven2
Downloading: http://repo.maven.apache.org/maven2/org/apache/struts/struts2-core/
2.1.8/struts2-core-2.1.8.jar
[DEBUG] Writing resolution tracking file D:\ProgramData\apache-maven-repo\.m2\re
pository\org\apache\struts\struts2-core\2.1.8\struts2-core-2.1.8.jar.lastUpdated
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 52:31.162s
[INFO] Finished at: Fri Jan 18 20:16:49 CST 2013
[INFO] Final Memory: 2M/5M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal on project Struts2Example: Could not resolve depe
ndencies for project com.mkyong.common:Struts2Example:war:com.mkyong.common: Cou
ld not transfer artifact org.apache.struts:struts2-core:jar:2.1.8 from/to centra
l (http://repo.maven.apache.org/maven2): GET request of: org/apache/struts/strut
s2-core/2.1.8/struts2-core-2.1.8.jar from central failed: Read timed out -> [Hel
p 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal o
n project Struts2Example: Could not resolve dependencies for project com.mkyong.
common:Struts2Example:war:com.mkyong.common: Could not transfer artifact org.apa
che.struts:struts2-core:jar:2.1.8 from/to central (http://repo.maven.apache.org/
maven2): GET request of: org/apache/struts/struts2-core/2.1.8/struts2-core-2.1.8
.jar from central failed
at org.apache.maven.lifecycle.internal.LifecycleDependencyResolver.getDe
pendencies(LifecycleDependencyResolver.java:210)
at org.apache.maven.lifecycle.internal.LifecycleDependencyResolver.resol
veProjectDependencies(LifecycleDependencyResolver.java:117)
at org.apache.maven.lifecycle.internal.MojoExecutor.ensureDependenciesAr
eResolved(MojoExecutor.java:258)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor
.java:201)
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.buildProje
ct(LifecycleModuleBuilder.java:84)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProje
ct(LifecycleModuleBuilder.java:59)
at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBu
ild(LifecycleStarter.java:183)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(Lifecycl
eStarter.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(DelegatingMethodAcces
sorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Laun
cher.java:290)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.jav
a:230)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(La
uncher.java:409)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:
352)
Caused by: org.apache.maven.project.DependencyResolutionException: Could not res
olve dependencies for project com.mkyong.common:Struts2Example:war:com.mkyong.co
mmon: Could not transfer artifact org.apache.struts:struts2-core:jar:2.1.8 from/
to central (http://repo.maven.apache.org/maven2): GET request of: org/apache/str
uts/struts2-core/2.1.8/struts2-core-2.1.8.jar from central failed
at org.apache.maven.project.DefaultProjectDependenciesResolver.resolve(D
efaultProjectDependenciesResolver.java:189)
at org.apache.maven.lifecycle.internal.LifecycleDependencyResolver.getDe
pendencies(LifecycleDependencyResolver.java:185)
... 22 more
Caused by: org.sonatype.aether.resolution.DependencyResolutionException: Could n
ot transfer artifact org.apache.struts:struts2-core:jar:2.1.8 from/to central (h
ttp://repo.maven.apache.org/maven2): GET request of: org/apache/struts/struts2-c
ore/2.1.8/struts2-core-2.1.8.jar from central failed
at org.sonatype.aether.impl.internal.DefaultRepositorySystem.resolveDepe
ndencies(DefaultRepositorySystem.java:375)
at org.apache.maven.project.DefaultProjectDependenciesResolver.resolve(D
efaultProjectDependenciesResolver.java:183)
... 23 more
Caused by: org.sonatype.aether.resolution.ArtifactResolutionException: Could not
transfer artifact org.apache.struts:struts2-core:jar:2.1.8 from/to central (htt
p://repo.maven.apache.org/maven2): GET request of: org/apache/struts/struts2-cor
e/2.1.8/struts2-core-2.1.8.jar from central failed
at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolve(Def
aultArtifactResolver.java:538)
at org.sonatype.aether.impl.internal.DefaultArtifactResolver.resolveArti
facts(DefaultArtifactResolver.java:216)
at org.sonatype.aether.impl.internal.DefaultRepositorySystem.resolveDepe
ndencies(DefaultRepositorySystem.java:358)
... 24 more
Caused by: org.sonatype.aether.transfer.ArtifactTransferException: Could not tra
nsfer artifact org.apache.struts:struts2-core:jar:2.1.8 from/to central (http://
repo.maven.apache.org/maven2): GET request of: org/apache/struts/struts2-core/2.
1.8/struts2-core-2.1.8.jar from central failed
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$4.wrap(W
agonRepositoryConnector.java:951)
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$4.wrap(W
agonRepositoryConnector.java:941)
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$GetTask.
run(WagonRepositoryConnector.java:669)
at org.sonatype.aether.util.concurrency.RunnableErrorForwarder$1.run(Run
nableErrorForwarder.java:60)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExec
utor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor
.java:908)
at java.lang.Thread.run(Thread.java:619)
Caused by: org.apache.maven.wagon.TransferFailedException: GET request of: org/a
pache/struts/struts2-core/2.1.8/struts2-core-2.1.8.jar from central failed
at org.apache.maven.wagon.AbstractWagon.getTransfer(AbstractWagon.java:3
49)
at org.apache.maven.wagon.AbstractWagon.getTransfer(AbstractWagon.java:3
10)
at org.apache.maven.wagon.AbstractWagon.getTransfer(AbstractWagon.java:2
87)
at org.apache.maven.wagon.StreamWagon.getIfNewer(StreamWagon.java:97)
at org.apache.maven.wagon.StreamWagon.get(StreamWagon.java:61)
at org.sonatype.aether.connector.wagon.WagonRepositoryConnector$GetTask.
run(WagonRepositoryConnector.java:601)
... 4 more
Caused by: java.net.SocketTimeoutException: Read timed out
at java.net.SocketInputStream.socketRead0(Native Method)
at java.net.SocketInputStream.read(SocketInputStream.java:129)
at org.apache.maven.wagon.providers.http.httpclient.impl.io.AbstractSess
ionInputBuffer.read(AbstractSessionInputBuffer.java:187)
at org.apache.maven.wagon.providers.http.httpclient.impl.io.ContentLengt
hInputStream.read(ContentLengthInputStream.java:176)
at org.apache.maven.wagon.providers.http.httpclient.conn.EofSensorInputS
tream.read(EofSensorInputStream.java:138)
at org.apache.maven.wagon.AbstractWagon.transfer(AbstractWagon.java:493)
at org.apache.maven.wagon.AbstractWagon.getTransfer(AbstractWagon.java:3
39)
... 9 more