code: protected void setCatalogs(List<File> pCatalogFiles, List<URL> pCatalogUrls ) throws MojoExecutionException
      {
          if ( catalogs == null || catalogs.length == 0 )
          {
              return;
          }
  
          for ( int i = 0; i < catalogs.length; i++ )
          {
              try
              {
                  URL url = new URL( catalogs[i] );
                  pCatalogUrls.add( url );
              }
              catch ( MalformedURLException e )
              {
                  File absoluteCatalog = asAbsoluteFile( new File( catalogs[i] ) );
                  if (!absoluteCatalog.exists() || !absoluteCatalog.isFile()){
                      throw new MojoExecutionException("That catalog does not exist:"+absoluteCatalog.getPath(), e);
                  }
                  pCatalogFiles.add(absoluteCatalog  );
              }
          }
      }
docs: Returns the plugins catalog files.