@Test
public void testRoundTrip() {
int positionCount = 40;
// build dictionary
BlockBuilder dictionaryBuilder = VARCHAR.createBlockBuilder(new BlockBuilderStatus(), 4);
VARCHAR.writeString(dictionaryBuilder, "alice");
VARCHAR.writeString(dictionaryBuilder, "bob");
VARCHAR.writeString(dictionaryBuilder, "charlie");
VARCHAR.writeString(dictionaryBuilder, "dave");
Block dictionary = dictionaryBuilder.build();
// build ids
int[] ids = new int[positionCount];
for (int i = 0; i < 40; i++) {
ids[i] = i % 4;
}
BlockEncoding blockEncoding = new DictionaryBlockEncoding(new VariableWidthBlockEncoding());
DictionaryBlock dictionaryBlock = new DictionaryBlock(positionCount, dictionary, ids);
DynamicSliceOutput sliceOutput = new DynamicSliceOutput(1024);
blockEncoding.writeBlock(sliceOutput, dictionaryBlock);
Block actualBlock = blockEncoding.readBlock(sliceOutput.slice().getInput());
assertTrue(actualBlock instanceof DictionaryBlock);
DictionaryBlock actualDictionaryBlock = (DictionaryBlock) actualBlock;
assertBlockEquals(VARCHAR, actualDictionaryBlock.getDictionary(), dictionary);
for (int position = 0; position < actualDictionaryBlock.getPositionCount(); position++) {
assertEquals(actualDictionaryBlock.getId(position), ids[position]);
}
assertEquals(
actualDictionaryBlock.getDictionarySourceId(), dictionaryBlock.getDictionarySourceId());
}
@Override
protected RunLengthEncodedBlockCursor createTestCursor() {
Block value = VARCHAR.createBlockBuilder(new BlockBuilderStatus()).appendNull().build();
return new RunLengthEncodedBlock(value, 11).cursor();
}
