Detecting Snapshot Versions in Maven Projects | Sonatype

I answer this question often enough that I decided to burn it to a blog, so I don't have to dig it out of the source anymore... and maybe save someone else the time along the way.

Here is the relevant code Maven uses to determine if an artifact is a snapshot or not:

<span style="font-family: arial;">String LATEST_VERSION = "LATEST";
String SNAPSHOT_VERSION = "SNAPSHOT";
Pattern VERSION_FILE_PATTERN = Pattern.compile(
 "^(.*)-([0-9]{8}.[0-9]{6})-([0-9]+)$" );
public boolean isSnapshot()
{
     if ( version != null || baseVersion != null )
     {
       Matcher m = VERSION_FILE_PATTERN.matcher( getBaseVersion() );
       if ( m.matches() )
       {
          setBaseVersion( m.group( 1 ) + "-" + SNAPSHOT_VERSION );
          return true;
       }
       else
       {
         return getBaseVersion().endsWith( SNAPSHOT_VERSION ) ||
         getBaseVersion().equals( LATEST_VERSION );
       }
     }
     else
     {
       return false;
     }
  }
</span>

Essentially, this regex (regular expression) checks if the version ends with Snapshot or if the pattern matches a timestamped version, such as "2.0.10-20080415.233129-15."