public Message(int numberOfParts,Version destVersion){
  this.version=destVersion;
  Assert.assertTrue(destVersion != null,"Attempt to create an unversioned message");
  partsList=new Part[numberOfParts];
  this.numberOfParts=numberOfParts;
  for (int i=0; i < partsList.length; i++) {
    partsList[i]=new Part();
  }
}

public Message ( int numberOfParts , Version destVersion ) { this . version = destVersion ; Assert . assertTrue ( destVersion != null , "Attempt to create an unversioned message" ) ; partsList = new Part [ numberOfParts ] ; this . numberOfParts = numberOfParts ; for ( int i = 0 ; i < partsList . length ; i ++ ) { partsList [ i ] = new Part ( ) ; } }
creates a new message with the given number of parts
