org.apache.arrow.algorithm.dictionary

Interface DictionaryEncoder<E extends BaseIntVector,D extends ValueVector>

Type Parameters:

E - type of the encoded vector.

D - type of the vector to encode. It is also the type of the dictionary vector.

All Known Implementing Classes:

HashTableDictionaryEncoder, LinearDictionaryEncoder, SearchDictionaryEncoder

public interface DictionaryEncoder<E extends BaseIntVector,D extends ValueVector>

A dictionary encoder translates one vector into another one based on a dictionary vector. According to Arrow specification, the encoded vector must be an integer based vector, which is the index of the original vector element in the dictionary.

Method Summary

Modifier and Type	Method and Description
void	encode(D input, E output) Translates an input vector into an output vector.

Method Detail

encode

void encode(D input,
            E output)

Translates an input vector into an output vector.

Parameters:

input - the input vector.

output - the output vector. Note that it must be in a fresh state. At least, all its validity bits should be clear.