code: public void build(byte[][] keys, int[] values)
      {
          Keyset keyset = new Keyset(keys, values);
          DoubleArrayBuilder builder = new DoubleArrayBuilder();
          builder.build(keyset);
  
          _array = builder.copy();
      }
docs: 构建
  
  @param keys   字节形式的键
  @param values 值