private void initDataReader(Encoding dataEncoding, byte[] bytes, int offset) throws IOException {
this.endOfPageValueCount = valuesRead + pageValueCount;
if (dataEncoding.usesDictionary()) {
this.dataColumn = null;
if (dictionary == null) {
throw new IOException(
"could not read page in col "
+ descriptor
+ " as the dictionary was missing for encoding "
+ dataEncoding);
}
@SuppressWarnings("deprecation")
Encoding plainDict = Encoding.PLAIN_DICTIONARY; // var to allow warning suppression
if (dataEncoding != plainDict && dataEncoding != Encoding.RLE_DICTIONARY) {
throw new UnsupportedOperationException("Unsupported encoding: " + dataEncoding);
}
this.dataColumn = new VectorizedRleValuesReader();
this.isCurrentPageDictionaryEncoded = true;
} else {
if (dataEncoding != Encoding.PLAIN) {
throw new UnsupportedOperationException("Unsupported encoding: " + dataEncoding);
}
this.dataColumn = new VectorizedPlainValuesReader();
this.isCurrentPageDictionaryEncoded = false;
}
try {
dataColumn.initFromPage(pageValueCount, bytes, offset);
} catch (IOException e) {
throw new IOException("could not read page in col " + descriptor, e);
}
}
private void readPageV1(DataPageV1 page) throws IOException {
this.pageValueCount = page.getValueCount();
ValuesReader rlReader = page.getRlEncoding().getValuesReader(descriptor, REPETITION_LEVEL);
ValuesReader dlReader;
// Initialize the decoders.
if (page.getDlEncoding() != Encoding.RLE && descriptor.getMaxDefinitionLevel() != 0) {
throw new UnsupportedOperationException("Unsupported encoding: " + page.getDlEncoding());
}
int bitWidth = BytesUtils.getWidthFromMaxInt(descriptor.getMaxDefinitionLevel());
this.defColumn = new VectorizedRleValuesReader(bitWidth);
dlReader = this.defColumn;
this.repetitionLevelColumn = new ValuesReaderIntIterator(rlReader);
this.definitionLevelColumn = new ValuesReaderIntIterator(dlReader);
try {
byte[] bytes = page.getBytes().toByteArray();
rlReader.initFromPage(pageValueCount, bytes, 0);
int next = rlReader.getNextOffset();
dlReader.initFromPage(pageValueCount, bytes, next);
next = dlReader.getNextOffset();
initDataReader(page.getValueEncoding(), bytes, next);
} catch (IOException e) {
throw new IOException("could not read page " + page + " in col " + descriptor, e);
}
}