Examples with StringObjectInspector org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector used on opensource projects

Example 11 with StringObjectInspector

use of org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector in project hive by apache.

the class ColumnStatsTask method unpackPrimitiveObject.

private void unpackPrimitiveObject(ObjectInspector oi, Object o, String fieldName, ColumnStatisticsObj statsObj) {
    if (o == null) {
        return;
    }
    // First infer the type of object
    if (fieldName.equals("columntype")) {
        PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
        String s = ((StringObjectInspector) poi).getPrimitiveJavaObject(o);
        ColumnStatisticsData statsData = new ColumnStatisticsData();
        if (s.equalsIgnoreCase("long")) {
            LongColumnStatsData longStats = new LongColumnStatsData();
            statsData.setLongStats(longStats);
            statsObj.setStatsData(statsData);
        } else if (s.equalsIgnoreCase("double")) {
            DoubleColumnStatsData doubleStats = new DoubleColumnStatsData();
            statsData.setDoubleStats(doubleStats);
            statsObj.setStatsData(statsData);
        } else if (s.equalsIgnoreCase("string")) {
            StringColumnStatsData stringStats = new StringColumnStatsData();
            statsData.setStringStats(stringStats);
            statsObj.setStatsData(statsData);
        } else if (s.equalsIgnoreCase("boolean")) {
            BooleanColumnStatsData booleanStats = new BooleanColumnStatsData();
            statsData.setBooleanStats(booleanStats);
            statsObj.setStatsData(statsData);
        } else if (s.equalsIgnoreCase("binary")) {
            BinaryColumnStatsData binaryStats = new BinaryColumnStatsData();
            statsData.setBinaryStats(binaryStats);
            statsObj.setStatsData(statsData);
        } else if (s.equalsIgnoreCase("decimal")) {
            DecimalColumnStatsData decimalStats = new DecimalColumnStatsData();
            statsData.setDecimalStats(decimalStats);
            statsObj.setStatsData(statsData);
        } else if (s.equalsIgnoreCase("date")) {
            DateColumnStatsData dateStats = new DateColumnStatsData();
            statsData.setDateStats(dateStats);
            statsObj.setStatsData(statsData);
        }
    } else {
        // invoke the right unpack method depending on data type of the column
        if (statsObj.getStatsData().isSetBooleanStats()) {
            unpackBooleanStats(oi, o, fieldName, statsObj);
        } else if (statsObj.getStatsData().isSetLongStats()) {
            unpackLongStats(oi, o, fieldName, statsObj);
        } else if (statsObj.getStatsData().isSetDoubleStats()) {
            unpackDoubleStats(oi, o, fieldName, statsObj);
        } else if (statsObj.getStatsData().isSetStringStats()) {
            unpackStringStats(oi, o, fieldName, statsObj);
        } else if (statsObj.getStatsData().isSetBinaryStats()) {
            unpackBinaryStats(oi, o, fieldName, statsObj);
        } else if (statsObj.getStatsData().isSetDecimalStats()) {
            unpackDecimalStats(oi, o, fieldName, statsObj);
        } else if (statsObj.getStatsData().isSetDateStats()) {
            unpackDateStats(oi, o, fieldName, statsObj);
        }
    }
}

Example 12 with StringObjectInspector

use of org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector in project hive by apache.

the class ColumnStatsTask method unpackDecimalStats.

private void unpackDecimalStats(ObjectInspector oi, Object o, String fName, ColumnStatisticsObj statsObj) {
    if (fName.equals("countnulls")) {
        long v = ((LongObjectInspector) oi).get(o);
        statsObj.getStatsData().getDecimalStats().setNumNulls(v);
    } else if (fName.equals("numdistinctvalues")) {
        long v = ((LongObjectInspector) oi).get(o);
        statsObj.getStatsData().getDecimalStats().setNumDVs(v);
    } else if (fName.equals("max")) {
        HiveDecimal d = ((HiveDecimalObjectInspector) oi).getPrimitiveJavaObject(o);
        statsObj.getStatsData().getDecimalStats().setHighValue(convertToThriftDecimal(d));
    } else if (fName.equals("min")) {
        HiveDecimal d = ((HiveDecimalObjectInspector) oi).getPrimitiveJavaObject(o);
        statsObj.getStatsData().getDecimalStats().setLowValue(convertToThriftDecimal(d));
    } else if (fName.equals("ndvbitvector")) {
        PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
        String v = ((StringObjectInspector) poi).getPrimitiveJavaObject(o);
        statsObj.getStatsData().getDecimalStats().setBitVectors(v);
        ;
    }
}

Example 13 with StringObjectInspector

use of org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector in project hive by apache.

the class JsonSerDe method buildJSONString.

// TODO : code section copied over from SerDeUtils because of non-standard json production there
// should use quotes for all field names. We should fix this there, and then remove this copy.
// See http://jackson.codehaus.org/1.7.3/javadoc/org/codehaus/jackson/JsonParser.Feature.html#ALLOW_UNQUOTED_FIELD_NAMES
// for details - trying to enable Jackson to ignore that doesn't seem to work(compilation failure
// when attempting to use that feature, so having to change the production itself.
// Also, throws IOException when Binary is detected.
private static void buildJSONString(StringBuilder sb, Object o, ObjectInspector oi) throws IOException {
    switch(oi.getCategory()) {
        case PRIMITIVE:
            {
                PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
                if (o == null) {
                    sb.append("null");
                } else {
                    switch(poi.getPrimitiveCategory()) {
                        case BOOLEAN:
                            {
                                boolean b = ((BooleanObjectInspector) poi).get(o);
                                sb.append(b ? "true" : "false");
                                break;
                            }
                        case BYTE:
                            {
                                sb.append(((ByteObjectInspector) poi).get(o));
                                break;
                            }
                        case SHORT:
                            {
                                sb.append(((ShortObjectInspector) poi).get(o));
                                break;
                            }
                        case INT:
                            {
                                sb.append(((IntObjectInspector) poi).get(o));
                                break;
                            }
                        case LONG:
                            {
                                sb.append(((LongObjectInspector) poi).get(o));
                                break;
                            }
                        case FLOAT:
                            {
                                sb.append(((FloatObjectInspector) poi).get(o));
                                break;
                            }
                        case DOUBLE:
                            {
                                sb.append(((DoubleObjectInspector) poi).get(o));
                                break;
                            }
                        case STRING:
                            {
                                String s = SerDeUtils.escapeString(((StringObjectInspector) poi).getPrimitiveJavaObject(o));
                                appendWithQuotes(sb, s);
                                break;
                            }
                        case BINARY:
                            {
                                throw new IOException("JsonSerDe does not support BINARY type");
                            }
                        case DATE:
                            Date d = ((DateObjectInspector) poi).getPrimitiveJavaObject(o);
                            appendWithQuotes(sb, d.toString());
                            break;
                        case TIMESTAMP:
                            {
                                Timestamp t = ((TimestampObjectInspector) poi).getPrimitiveJavaObject(o);
                                appendWithQuotes(sb, t.toString());
                                break;
                            }
                        case DECIMAL:
                            sb.append(((HiveDecimalObjectInspector) poi).getPrimitiveJavaObject(o));
                            break;
                        case VARCHAR:
                            {
                                String s = SerDeUtils.escapeString(((HiveVarcharObjectInspector) poi).getPrimitiveJavaObject(o).toString());
                                appendWithQuotes(sb, s);
                                break;
                            }
                        case CHAR:
                            {
                                //this should use HiveChar.getPaddedValue() but it's protected; currently (v0.13)
                                // HiveChar.toString() returns getPaddedValue()
                                String s = SerDeUtils.escapeString(((HiveCharObjectInspector) poi).getPrimitiveJavaObject(o).toString());
                                appendWithQuotes(sb, s);
                                break;
                            }
                        default:
                            throw new RuntimeException("Unknown primitive type: " + poi.getPrimitiveCategory());
                    }
                }
                break;
            }
        case LIST:
            {
                ListObjectInspector loi = (ListObjectInspector) oi;
                ObjectInspector listElementObjectInspector = loi.getListElementObjectInspector();
                List<?> olist = loi.getList(o);
                if (olist == null) {
                    sb.append("null");
                } else {
                    sb.append(SerDeUtils.LBRACKET);
                    for (int i = 0; i < olist.size(); i++) {
                        if (i > 0) {
                            sb.append(SerDeUtils.COMMA);
                        }
                        buildJSONString(sb, olist.get(i), listElementObjectInspector);
                    }
                    sb.append(SerDeUtils.RBRACKET);
                }
                break;
            }
        case MAP:
            {
                MapObjectInspector moi = (MapObjectInspector) oi;
                ObjectInspector mapKeyObjectInspector = moi.getMapKeyObjectInspector();
                ObjectInspector mapValueObjectInspector = moi.getMapValueObjectInspector();
                Map<?, ?> omap = moi.getMap(o);
                if (omap == null) {
                    sb.append("null");
                } else {
                    sb.append(SerDeUtils.LBRACE);
                    boolean first = true;
                    for (Object entry : omap.entrySet()) {
                        if (first) {
                            first = false;
                        } else {
                            sb.append(SerDeUtils.COMMA);
                        }
                        Map.Entry<?, ?> e = (Map.Entry<?, ?>) entry;
                        StringBuilder keyBuilder = new StringBuilder();
                        buildJSONString(keyBuilder, e.getKey(), mapKeyObjectInspector);
                        String keyString = keyBuilder.toString().trim();
                        if ((!keyString.isEmpty()) && (keyString.charAt(0) != SerDeUtils.QUOTE)) {
                            appendWithQuotes(sb, keyString);
                        } else {
                            sb.append(keyString);
                        }
                        sb.append(SerDeUtils.COLON);
                        buildJSONString(sb, e.getValue(), mapValueObjectInspector);
                    }
                    sb.append(SerDeUtils.RBRACE);
                }
                break;
            }
        case STRUCT:
            {
                StructObjectInspector soi = (StructObjectInspector) oi;
                List<? extends StructField> structFields = soi.getAllStructFieldRefs();
                if (o == null) {
                    sb.append("null");
                } else {
                    sb.append(SerDeUtils.LBRACE);
                    for (int i = 0; i < structFields.size(); i++) {
                        if (i > 0) {
                            sb.append(SerDeUtils.COMMA);
                        }
                        appendWithQuotes(sb, structFields.get(i).getFieldName());
                        sb.append(SerDeUtils.COLON);
                        buildJSONString(sb, soi.getStructFieldData(o, structFields.get(i)), structFields.get(i).getFieldObjectInspector());
                    }
                    sb.append(SerDeUtils.RBRACE);
                }
                break;
            }
        case UNION:
            {
                UnionObjectInspector uoi = (UnionObjectInspector) oi;
                if (o == null) {
                    sb.append("null");
                } else {
                    sb.append(SerDeUtils.LBRACE);
                    sb.append(uoi.getTag(o));
                    sb.append(SerDeUtils.COLON);
                    buildJSONString(sb, uoi.getField(o), uoi.getObjectInspectors().get(uoi.getTag(o)));
                    sb.append(SerDeUtils.RBRACE);
                }
                break;
            }
        default:
            throw new RuntimeException("Unknown type in ObjectInspector!");
    }
}

Example 14 with StringObjectInspector

use of org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector in project SQLWindowing by hbutani.

the class WindowingKeySerializer method serialize.

/*
	 * copied from BinarySortableSerDe::serialize
	 */
static void serialize(OutputByteBuffer buffer, Object o, ObjectInspector oi, boolean invert) {
    // Is this field a null?
    if (o == null) {
        buffer.write((byte) 0, invert);
        return;
    }
    // This field is not a null.
    buffer.write((byte) 1, invert);
    switch(oi.getCategory()) {
        case PRIMITIVE:
            {
                PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
                switch(poi.getPrimitiveCategory()) {
                    case VOID:
                        {
                            return;
                        }
                    case BOOLEAN:
                        {
                            boolean v = ((BooleanObjectInspector) poi).get(o);
                            buffer.write((byte) (v ? 2 : 1), invert);
                            return;
                        }
                    case BYTE:
                        {
                            ByteObjectInspector boi = (ByteObjectInspector) poi;
                            byte v = boi.get(o);
                            buffer.write((byte) (v ^ 0x80), invert);
                            return;
                        }
                    case SHORT:
                        {
                            ShortObjectInspector spoi = (ShortObjectInspector) poi;
                            short v = spoi.get(o);
                            buffer.write((byte) ((v >> 8) ^ 0x80), invert);
                            buffer.write((byte) v, invert);
                            return;
                        }
                    case INT:
                        {
                            IntObjectInspector ioi = (IntObjectInspector) poi;
                            int v = ioi.get(o);
                            buffer.write((byte) ((v >> 24) ^ 0x80), invert);
                            buffer.write((byte) (v >> 16), invert);
                            buffer.write((byte) (v >> 8), invert);
                            buffer.write((byte) v, invert);
                            return;
                        }
                    case LONG:
                        {
                            LongObjectInspector loi = (LongObjectInspector) poi;
                            long v = loi.get(o);
                            buffer.write((byte) ((v >> 56) ^ 0x80), invert);
                            buffer.write((byte) (v >> 48), invert);
                            buffer.write((byte) (v >> 40), invert);
                            buffer.write((byte) (v >> 32), invert);
                            buffer.write((byte) (v >> 24), invert);
                            buffer.write((byte) (v >> 16), invert);
                            buffer.write((byte) (v >> 8), invert);
                            buffer.write((byte) v, invert);
                            return;
                        }
                    case FLOAT:
                        {
                            FloatObjectInspector foi = (FloatObjectInspector) poi;
                            int v = Float.floatToIntBits(foi.get(o));
                            if ((v & (1 << 31)) != 0) {
                                // negative number, flip all bits
                                v = ~v;
                            } else {
                                // positive number, flip the first bit
                                v = v ^ (1 << 31);
                            }
                            buffer.write((byte) (v >> 24), invert);
                            buffer.write((byte) (v >> 16), invert);
                            buffer.write((byte) (v >> 8), invert);
                            buffer.write((byte) v, invert);
                            return;
                        }
                    case DOUBLE:
                        {
                            DoubleObjectInspector doi = (DoubleObjectInspector) poi;
                            long v = Double.doubleToLongBits(doi.get(o));
                            if ((v & (1L << 63)) != 0) {
                                // negative number, flip all bits
                                v = ~v;
                            } else {
                                // positive number, flip the first bit
                                v = v ^ (1L << 63);
                            }
                            buffer.write((byte) (v >> 56), invert);
                            buffer.write((byte) (v >> 48), invert);
                            buffer.write((byte) (v >> 40), invert);
                            buffer.write((byte) (v >> 32), invert);
                            buffer.write((byte) (v >> 24), invert);
                            buffer.write((byte) (v >> 16), invert);
                            buffer.write((byte) (v >> 8), invert);
                            buffer.write((byte) v, invert);
                            return;
                        }
                    case STRING:
                        {
                            StringObjectInspector soi = (StringObjectInspector) poi;
                            Text t = soi.getPrimitiveWritableObject(o);
                            byte[] data = t.getBytes();
                            int length = t.getLength();
                            for (int i = 0; i < length; i++) {
                                if (data[i] == 0 || data[i] == 1) {
                                    buffer.write((byte) 1, invert);
                                    buffer.write((byte) (data[i] + 1), invert);
                                } else {
                                    buffer.write(data[i], invert);
                                }
                            }
                            buffer.write((byte) 0, invert);
                            return;
                        }
                    default:
                        {
                            throw new RuntimeException("Unrecognized type: " + poi.getPrimitiveCategory());
                        }
                }
            }
        default:
            {
                throw new RuntimeException("Unsupported type in WindowingKey : " + oi.getCategory());
            }
    }
}

Example 15 with StringObjectInspector

use of org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector in project hive by apache.

the class LazyBinarySerDe method serialize.

/**
   * A recursive function that serialize an object to a byte buffer based on its
   * object inspector.
   *
   * @param byteStream
   *          the byte stream storing the serialization data
   * @param obj
   *          the object to serialize
   * @param objInspector
   *          the object inspector
   * @param skipLengthPrefix a boolean indicating whether length prefix is
   *          needed for list/map/struct
   * @param warnedOnceNullMapKey a boolean indicating whether a warning
   *          has been issued once already when encountering null map keys
   */
public static void serialize(RandomAccessOutput byteStream, Object obj, ObjectInspector objInspector, boolean skipLengthPrefix, BooleanRef warnedOnceNullMapKey) throws SerDeException {
    // do nothing for null object
    if (null == obj) {
        return;
    }
    switch(objInspector.getCategory()) {
        case PRIMITIVE:
            {
                PrimitiveObjectInspector poi = (PrimitiveObjectInspector) objInspector;
                switch(poi.getPrimitiveCategory()) {
                    case VOID:
                        {
                            return;
                        }
                    case BOOLEAN:
                        {
                            boolean v = ((BooleanObjectInspector) poi).get(obj);
                            byteStream.write((byte) (v ? 1 : 0));
                            return;
                        }
                    case BYTE:
                        {
                            ByteObjectInspector boi = (ByteObjectInspector) poi;
                            byte v = boi.get(obj);
                            byteStream.write(v);
                            return;
                        }
                    case SHORT:
                        {
                            ShortObjectInspector spoi = (ShortObjectInspector) poi;
                            short v = spoi.get(obj);
                            byteStream.write((byte) (v >> 8));
                            byteStream.write((byte) (v));
                            return;
                        }
                    case INT:
                        {
                            IntObjectInspector ioi = (IntObjectInspector) poi;
                            int v = ioi.get(obj);
                            LazyBinaryUtils.writeVInt(byteStream, v);
                            return;
                        }
                    case LONG:
                        {
                            LongObjectInspector loi = (LongObjectInspector) poi;
                            long v = loi.get(obj);
                            LazyBinaryUtils.writeVLong(byteStream, v);
                            return;
                        }
                    case FLOAT:
                        {
                            FloatObjectInspector foi = (FloatObjectInspector) poi;
                            int v = Float.floatToIntBits(foi.get(obj));
                            byteStream.write((byte) (v >> 24));
                            byteStream.write((byte) (v >> 16));
                            byteStream.write((byte) (v >> 8));
                            byteStream.write((byte) (v));
                            return;
                        }
                    case DOUBLE:
                        {
                            DoubleObjectInspector doi = (DoubleObjectInspector) poi;
                            LazyBinaryUtils.writeDouble(byteStream, doi.get(obj));
                            return;
                        }
                    case STRING:
                        {
                            StringObjectInspector soi = (StringObjectInspector) poi;
                            Text t = soi.getPrimitiveWritableObject(obj);
                            serializeText(byteStream, t, skipLengthPrefix);
                            return;
                        }
                    case CHAR:
                        {
                            HiveCharObjectInspector hcoi = (HiveCharObjectInspector) poi;
                            Text t = hcoi.getPrimitiveWritableObject(obj).getTextValue();
                            serializeText(byteStream, t, skipLengthPrefix);
                            return;
                        }
                    case VARCHAR:
                        {
                            HiveVarcharObjectInspector hcoi = (HiveVarcharObjectInspector) poi;
                            Text t = hcoi.getPrimitiveWritableObject(obj).getTextValue();
                            serializeText(byteStream, t, skipLengthPrefix);
                            return;
                        }
                    case BINARY:
                        {
                            BinaryObjectInspector baoi = (BinaryObjectInspector) poi;
                            BytesWritable bw = baoi.getPrimitiveWritableObject(obj);
                            int length = bw.getLength();
                            if (!skipLengthPrefix) {
                                LazyBinaryUtils.writeVInt(byteStream, length);
                            } else {
                                if (length == 0) {
                                    throw new RuntimeException("LazyBinaryColumnarSerde cannot serialize a non-null zero " + "length binary field. Consider using either LazyBinarySerde or ColumnarSerde.");
                                }
                            }
                            byteStream.write(bw.getBytes(), 0, length);
                            return;
                        }
                    case DATE:
                        {
                            DateWritable d = ((DateObjectInspector) poi).getPrimitiveWritableObject(obj);
                            writeDateToByteStream(byteStream, d);
                            return;
                        }
                    case TIMESTAMP:
                        {
                            TimestampObjectInspector toi = (TimestampObjectInspector) poi;
                            TimestampWritable t = toi.getPrimitiveWritableObject(obj);
                            t.writeToByteStream(byteStream);
                            return;
                        }
                    case INTERVAL_YEAR_MONTH:
                        {
                            HiveIntervalYearMonthWritable intervalYearMonth = ((HiveIntervalYearMonthObjectInspector) poi).getPrimitiveWritableObject(obj);
                            intervalYearMonth.writeToByteStream(byteStream);
                            return;
                        }
                    case INTERVAL_DAY_TIME:
                        {
                            HiveIntervalDayTimeWritable intervalDayTime = ((HiveIntervalDayTimeObjectInspector) poi).getPrimitiveWritableObject(obj);
                            intervalDayTime.writeToByteStream(byteStream);
                            return;
                        }
                    case DECIMAL:
                        {
                            HiveDecimalObjectInspector bdoi = (HiveDecimalObjectInspector) poi;
                            HiveDecimalWritable t = bdoi.getPrimitiveWritableObject(obj);
                            if (t == null) {
                                return;
                            }
                            writeToByteStream(byteStream, t);
                            return;
                        }
                    default:
                        {
                            throw new RuntimeException("Unrecognized type: " + poi.getPrimitiveCategory());
                        }
                }
            }
        case LIST:
            {
                ListObjectInspector loi = (ListObjectInspector) objInspector;
                ObjectInspector eoi = loi.getListElementObjectInspector();
                int byteSizeStart = 0;
                int listStart = 0;
                if (!skipLengthPrefix) {
                    // 1/ reserve spaces for the byte size of the list
                    // which is a integer and takes four bytes
                    byteSizeStart = byteStream.getLength();
                    byteStream.reserve(4);
                    listStart = byteStream.getLength();
                }
                // 2/ write the size of the list as a VInt
                int size = loi.getListLength(obj);
                LazyBinaryUtils.writeVInt(byteStream, size);
                // 3/ write the null bytes
                byte nullByte = 0;
                for (int eid = 0; eid < size; eid++) {
                    // set the bit to 1 if an element is not null
                    if (null != loi.getListElement(obj, eid)) {
                        nullByte |= 1 << (eid % 8);
                    }
                    // if this is the last element
                    if (7 == eid % 8 || eid == size - 1) {
                        byteStream.write(nullByte);
                        nullByte = 0;
                    }
                }
                // 4/ write element by element from the list
                for (int eid = 0; eid < size; eid++) {
                    serialize(byteStream, loi.getListElement(obj, eid), eoi, false, warnedOnceNullMapKey);
                }
                if (!skipLengthPrefix) {
                    // 5/ update the list byte size
                    int listEnd = byteStream.getLength();
                    int listSize = listEnd - listStart;
                    writeSizeAtOffset(byteStream, byteSizeStart, listSize);
                }
                return;
            }
        case MAP:
            {
                MapObjectInspector moi = (MapObjectInspector) objInspector;
                ObjectInspector koi = moi.getMapKeyObjectInspector();
                ObjectInspector voi = moi.getMapValueObjectInspector();
                Map<?, ?> map = moi.getMap(obj);
                int byteSizeStart = 0;
                int mapStart = 0;
                if (!skipLengthPrefix) {
                    // 1/ reserve spaces for the byte size of the map
                    // which is a integer and takes four bytes
                    byteSizeStart = byteStream.getLength();
                    byteStream.reserve(4);
                    mapStart = byteStream.getLength();
                }
                // 2/ write the size of the map which is a VInt
                int size = map.size();
                LazyBinaryUtils.writeVInt(byteStream, size);
                // 3/ write the null bytes
                int b = 0;
                byte nullByte = 0;
                for (Map.Entry<?, ?> entry : map.entrySet()) {
                    // set the bit to 1 if a key is not null
                    if (null != entry.getKey()) {
                        nullByte |= 1 << (b % 8);
                    } else if (warnedOnceNullMapKey != null) {
                        if (!warnedOnceNullMapKey.value) {
                            LOG.warn("Null map key encountered! Ignoring similar problems.");
                        }
                        warnedOnceNullMapKey.value = true;
                    }
                    b++;
                    // set the bit to 1 if a value is not null
                    if (null != entry.getValue()) {
                        nullByte |= 1 << (b % 8);
                    }
                    b++;
                    // or if this is the last key-value pair
                    if (0 == b % 8 || b == size * 2) {
                        byteStream.write(nullByte);
                        nullByte = 0;
                    }
                }
                // 4/ write key-value pairs one by one
                for (Map.Entry<?, ?> entry : map.entrySet()) {
                    serialize(byteStream, entry.getKey(), koi, false, warnedOnceNullMapKey);
                    serialize(byteStream, entry.getValue(), voi, false, warnedOnceNullMapKey);
                }
                if (!skipLengthPrefix) {
                    // 5/ update the byte size of the map
                    int mapEnd = byteStream.getLength();
                    int mapSize = mapEnd - mapStart;
                    writeSizeAtOffset(byteStream, byteSizeStart, mapSize);
                }
                return;
            }
        case STRUCT:
        case UNION:
            {
                int byteSizeStart = 0;
                int typeStart = 0;
                if (!skipLengthPrefix) {
                    // 1/ reserve spaces for the byte size of the struct
                    // which is a integer and takes four bytes
                    byteSizeStart = byteStream.getLength();
                    byteStream.reserve(4);
                    typeStart = byteStream.getLength();
                }
                if (ObjectInspector.Category.STRUCT.equals(objInspector.getCategory())) {
                    // 2/ serialize the struct
                    serializeStruct(byteStream, obj, (StructObjectInspector) objInspector, warnedOnceNullMapKey);
                } else {
                    // 2/ serialize the union
                    serializeUnion(byteStream, obj, (UnionObjectInspector) objInspector, warnedOnceNullMapKey);
                }
                if (!skipLengthPrefix) {
                    // 3/ update the byte size of the struct
                    int typeEnd = byteStream.getLength();
                    int typeSize = typeEnd - typeStart;
                    writeSizeAtOffset(byteStream, byteSizeStart, typeSize);
                }
                return;
            }
        default:
            {
                throw new RuntimeException("Unrecognized type: " + objInspector.getCategory());
            }
    }
}