Mystifying generics problem (or perhaps I am just stupid?)

Question

Given the following class:
public class DataTextFileReader<T> {
     private Vector<T> builtVector = null;
     public Vector<T> getData() {return builtVector;}
}And these instructions in another class:
DataTextFileReader theFileReader = new DataTextFileReader<Kanji>();
Vector<Kanji> builtVector = theFileReader.getData();Why do I get an unchecked type warning from the call to getData()?
Of course, the above code is drastically simplified. In actuality the constructor for DataTextFileReader is like so:
public DataTextFileReader(File inputFile, LineParser<T> theLineParser)And the line I am instantiating it with is like so:
new DataTextFileReader<Kanji>(inputFile, (LineParser<Kanji>)new KanjiDetabber());And of course, there is a Kanji class, a LineParser<K> interface, and a KanjiDetabber class which implements LineParser in the picture. LineParser defines a parseLine method used to built objects from lines passed from the DataTextFileReader (in the case of KanjiDetabber, Kanji objects). DataTextFileReader basically just uses the LineParser to build objects which it puts into builtVector, and keeps track of bad lines. I am using this to read in data files in human-readable format so that I can do manual data entry into a text file and then just import everything.
But all of these compile without errors or warnings, and anyway nothing else should be relevant as long as the builtVector member and the getData() method have the right generics, right?
I take it I am not the only person who finds generics thoroughly vexing. Useful, but vexing.
Drake

Answer 1

Off topic: consider using ArrayList instead of Vector.
You need to use generics in all places:
DataTextFileReader<Kanji> theFileReader = new DataTextFileReader<Kanji>();Also, this example:
new DataTextFileReader<Kanji>(inputFile, (LineParser<Kanji>)new KanjiDetabber());Remove the cast:
new DataTextFileReader<Kanji>(inputFile, new KanjiDetabber());Make sure that KanjiDetabber is declared like this:
class KanjiDetabber extends LineParser<Kanji> { ... }Perhaps you would be happier with a different word
than Detabber, how about KanjiTabFilter.