public void loadCenter(FileSystem fs, Path  path, Configuration conf){
			SequenceFile.Reader reader ;
			try {
				
			reader = new SequenceFile.Reader(fs, path, conf);
			IntWritable key = (IntWritable) reader.getKeyClass().newInstance();
			FloatArrayWritable value = (FloatArrayWritable) reader.getValueClass().newInstance();
			while(reader.next(key, value))	{
				//System.out.println("key="+key.toString()+"value"+value.toString());
				int centerId = key.get();
				chkCenter[centerId] = true;
				FloatWritable[] vect = (FloatWritable[]) value.toArray();
				for(int i=0; i<10; i++) {
					centers[centerId][i]=vect[i].get();
				}
			}
			
			//generate new center for empty ones
			for(int i =0 ;i<Constant.NFLIX_K;i++) {
				if(!chkCenter[i]) {
					for(int j=0; j<10;j++) {
						float fet = (float) (-1+Kmath.getRandom()*2);
						centers[i][j]=fet;
					}
				}
			}
			reader.close();
			} catch(Exception e) {
				System.out.println("WARNING: No "+path.toString()+":Couldn't read cache file:"+e.toString());
			}
		}