Maven Snapshot Deployment policy Doubts

Question

as of now we used to check out entire project, and compile all the projects at all the time.

so now we want to checkout only which we want to modify,,so for that we implemented version to easily track where the modifications happens.

Let say we have project A
    Project B
    Project C

if i want to modify project C and i want to checkout only project C but project C has dependencies on A and B.

A and B has to download from the nexus. for every modifications on A and B, deploy the artifacts into nexus, and C will get those changes from nexus.

as i am mew to this concept, can any one let me know how to make this workable properly.. Questions

as i observed all snapshots are on time stamp based,which dependencies will download newest or oldest, if i want older snapshot as a dependency,what i have to do? any best practice suggestions?

Adding Error Code:-

when using -T 1.5C i am getting this error:

java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:60)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
at java.lang.reflect.Method.invoke(Method.java:611)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchStandard(Launcher.java:330)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:238)
at jenkins.maven3.agent.Maven32Main.launch(Maven32Main.java:181)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:60)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37)
at java.lang.reflect.Method.invoke(Method.java:611)
at hudson.maven.Maven3Builder.call(Maven3Builder.java:136)
at hudson.maven.Maven3Builder.call(Maven3Builder.java:71)
at hudson.remoting.UserRequest.perform(UserRequest.java:121)
at hudson.remoting.UserRequest.perform(UserRequest.java:49)
at hudson.remoting.Request$2.run(Request.java:324)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:314)
at java.util.concurrent.FutureTask.run(FutureTask.java:149)
at    java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:906)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:929)
at java.lang.Thread.run(Thread.java:738)
 Caused by: org.apache.maven.cli.MavenExecutionRequestsBuilderException: Must provide a thread count for -T
at org.apache.maven.cli.DefaultMavenExecutionRequestBuilder.getMavenExecutionRequest(DefaultMavenExecutionRequestBuilder.java:192)
at org.jvnet.hudson.maven3.launcher.Maven32Launcher.getMavenExecutionRequest(Maven32Launcher.java:153)
at org.jvnet.hudson.maven3.launcher.Maven32Launcher.main(Maven32Launcher.java:130)
... 22 more
 Caused by: java.lang.IllegalArgumentException: Must provide a thread count for -T
at org.apache.maven.cli.DefaultMavenExecutionRequestBuilder.populateRequest(DefaultMavenExecutionRequestBuilder.java:982)
at org.apache.maven.cli.DefaultMavenExecutionRequestBuilder.getMavenExecutionRequest(DefaultMavenExecutionRequestBuilder.java:172)
... 24 more
  ERROR: Failed to parse POMs
  java.io.IOException: Remote call on Channel to Maven [/opt/ibm/java-x86_64-60/bin/java, -cp, /var/lib/jenkins/plugins/maven-plugin/WEB-INF/lib/maven32-agent-1.6.jar:/opt/apache/apache-maven-3.2.5/boot/plexus-classworlds-2.5.2.jar:/opt/apache/apache-maven-3.2.5/conf/logging, jenkins.maven3.agent.Maven32Main, /opt/apache/apache-maven-3.2.5, /var/cache/jenkins/war/WEB-INF/lib/remoting-2.49.jar, /var/lib/jenkins/plugins/maven-plugin/WEB-INF/lib/maven32-interceptor-1.6.jar, /var/lib/jenkins/plugins/maven-plugin/WEB-INF/lib/maven3-interceptor-commons-1.6.jar, 45090] failed
at hudson.remoting.Channel.call(Channel.java:756)
at hudson.maven.ProcessCache$MavenProcess.call(ProcessCache.java:161)
at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.doRun(MavenModuleSetBuild.java:849)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:536)
at hudson.model.Run.execute(Run.java:1718)
at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:531)
at hudson.model.ResourceController.execute(ResourceController.java:89)
at hudson.model.Executor.run(Executor.java:240)
 Caused by: java.lang.ClassNotFoundException: org.apache.maven.cli.MavenExecutionRequestsBuilderException
at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:323)
at java.lang.ClassLoader.loadClass(ClassLoader.java:268)
at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:430)
at org.eclipse.jetty.webapp.WebAppClassLoader.loadClass(WebAppClassLoader.java:383)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:274)
at java.io.ObjectInputStream.resolveClass(ObjectInputStream.java:624)
at hudson.remoting.MultiClassLoaderSerializer$Input.resolveClass(MultiClassLoaderSerializer.java:116)
at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1611)
at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1516)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1770)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1349)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1989)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1914)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1797)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1349)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1989)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1914)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1797)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1349)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1989)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1914)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1797)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1349)
at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1989)
at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1914)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1797)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1349)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:369)
at hudson.remoting.UserRequest.deserialize(UserRequest.java:185)
at hudson.remoting.UserResponse.retrieve(UserRequest.java:218)
at hudson.remoting.Channel.call(Channel.java:752)
... 7 more

Answer 1

If you would like to use older states of SNAPSHOTs this can be achieved by defining the appropriate version in your pom:

The versions-maven-plugin can help in such cases to lock-snapshots or to unlock-snapshots .

Apart from that you should be aware of the update policy which can change in the settings.xml file. Or you can manually force to update via:

mvn -U ...