@Override
public boolean isSingleRow() {
if (!hashMapResult.hasRows()) {
return (dummyRow != null);
}
return hashMapResult.isSingleRow();
}
@Override
public void addRow(List<Object> t) {
if (dummyRow != null || hashMapResult.hasRows()) {
throw new RuntimeException("Cannot add rows when not empty");
}
dummyRow = t;
}
@Override
public void clearRows() {
// Doesn't clear underlying hashtable
hashMapResult.forget();
dummyRow = null;
aliasFilter = (byte) 0xff;
}
@Override
public List<Object> next() throws HiveException {
WriteBuffers.ByteSegmentRef byteSegmentRef = hashMapResult.next();
if (byteSegmentRef == null) {
return null;
} else {
return unpack(byteSegmentRef);
}
}
public JoinUtil.JoinResult setFromOutput(Output output) {
aliasFilter = hashMap.getValueResult(output.getData(), 0, output.getLength(), hashMapResult);
dummyRow = null;
if (hashMapResult.hasRows()) {
return JoinUtil.JoinResult.MATCH;
} else {
aliasFilter = (byte) 0xff;
return JoinUtil.JoinResult.NOMATCH;
}
}
public JoinUtil.JoinResult setDirect(
byte[] bytes, int offset, int length, BytesBytesMultiHashMap.Result hashMapResult) {
int keyHash = WriteBuffers.murmurHash(bytes, offset, length);
aliasFilter = hashMap.getValueResult(bytes, offset, length, hashMapResult);
dummyRow = null;
if (hashMapResult.hasRows()) {
return JoinUtil.JoinResult.MATCH;
} else {
aliasFilter = (byte) 0xff;
return JoinUtil.JoinResult.NOMATCH;
}
}
// Implementation of row iterator
@Override
public List<Object> first() throws HiveException {
// A little strange that we forget the dummy row on read.
if (dummyRow != null) {
List<Object> result = dummyRow;
dummyRow = null;
return result;
}
WriteBuffers.ByteSegmentRef byteSegmentRef = hashMapResult.first();
if (byteSegmentRef == null) {
return null;
} else {
return unpack(byteSegmentRef);
}
}
@Override
public boolean hasRows() {
return hashMapResult.hasRows() || (dummyRow != null);
}