docs: @Override
  	public int generateAt(Instance instance, IFeatureAlphabet features, int pos,
  			int... numLabels) {
  		String[][] data = ( String[][]) instance.getData();
  		int len = data[0].length;
  
  		StringBuilder sb = new StringBuilder();
  
  		sb.append(id);
  		sb.append(':');
  
  		for(int idx : idxs){
  			pos = pos+idx;
  			if(pos<0||pos>=len)
  				return -1;
  			String context = "";
  			if(pos>1)
  				context += data[0][pos-1]; //这里数据行列和模板中行列相反
  			else
  				context += "Begin0";
  			context += data[0][pos]; 
  			if(pos<len-1)
  				context += data[0][pos+1]; //这里数据行列和模板中行列相反
  			else
  				context += "End0";
  			// 得到字符串类型		
  			int cid;
  			char c = data[0][pos].charAt(0);
  			if(c>='A'+ 65248 &&c<='Z'+65248)
  				cid = 1039;
  			else
  				cid= cluster.classifier(context);
  			sb.append(":");
  			sb.append(cid);
  		}
  		int index = features.lookupIndex(sb.toString(),numLabels[0]);
  		return index;
  	}