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

Example 66 with StructField

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

the class ObjectInspectorUtils method getConstantObjectInspector.

public static ConstantObjectInspector getConstantObjectInspector(ObjectInspector oi, Object value) {
    if (oi instanceof ConstantObjectInspector) {
        return (ConstantObjectInspector) oi;
    }
    ObjectInspector writableOI = getStandardObjectInspector(oi, ObjectInspectorCopyOption.WRITABLE);
    Object writableValue = value == null ? value : ObjectInspectorConverters.getConverter(oi, writableOI).convert(value);
    switch(writableOI.getCategory()) {
        case PRIMITIVE:
            PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
            return PrimitiveObjectInspectorFactory.getPrimitiveWritableConstantObjectInspector(poi.getTypeInfo(), writableValue);
        case LIST:
            ListObjectInspector loi = (ListObjectInspector) oi;
            return ObjectInspectorFactory.getStandardConstantListObjectInspector(getStandardObjectInspector(loi.getListElementObjectInspector(), ObjectInspectorCopyOption.WRITABLE), (List<?>) writableValue);
        case MAP:
            MapObjectInspector moi = (MapObjectInspector) oi;
            return ObjectInspectorFactory.getStandardConstantMapObjectInspector(getStandardObjectInspector(moi.getMapKeyObjectInspector(), ObjectInspectorCopyOption.WRITABLE), getStandardObjectInspector(moi.getMapValueObjectInspector(), ObjectInspectorCopyOption.WRITABLE), (Map<?, ?>) writableValue);
        case STRUCT:
            StructObjectInspector soi = (StructObjectInspector) oi;
            List<? extends StructField> fields = soi.getAllStructFieldRefs();
            List<String> fieldNames = new ArrayList<String>(fields.size());
            List<ObjectInspector> fieldObjectInspectors = new ArrayList<ObjectInspector>(fields.size());
            for (StructField f : fields) {
                fieldNames.add(f.getFieldName());
                fieldObjectInspectors.add(getStandardObjectInspector(f.getFieldObjectInspector(), ObjectInspectorCopyOption.WRITABLE));
            }
            if (value != null && (writableValue.getClass().isArray())) {
                writableValue = java.util.Arrays.asList((Object[]) writableValue);
            }
            return ObjectInspectorFactory.getStandardConstantStructObjectInspector(fieldNames, fieldObjectInspectors, (List<?>) writableValue);
        default:
            throw new IllegalArgumentException(writableOI.getCategory() + " not yet supported for constant OI");
    }
}

Example 67 with StructField

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

the class ObjectInspectorUtils method hasAllFieldsSettable.

/**
 * @param oi - Input object inspector
 * @param oiSettableProperties - Lookup map to cache the result.(If no caching, pass null)
 * @return - true if : (1) oi is an instance of settable<DataType>OI.
 *                     (2) All the embedded object inspectors are instances of settable<DataType>OI.
 *           If (1) or (2) is false, return false.
 */
public static boolean hasAllFieldsSettable(ObjectInspector oi, Map<ObjectInspector, Boolean> oiSettableProperties) {
    // If the result is already present in the cache, return it.
    if (!(oiSettableProperties == null) && oiSettableProperties.containsKey(oi)) {
        return oiSettableProperties.get(oi).booleanValue();
    }
    // If the top-level object inspector is non-settable return false
    if (!(isInstanceOfSettableOI(oi))) {
        return setOISettablePropertiesMap(oi, oiSettableProperties, false);
    }
    Boolean returnValue = true;
    switch(oi.getCategory()) {
        case PRIMITIVE:
            break;
        case STRUCT:
            StructObjectInspector structOutputOI = (StructObjectInspector) oi;
            List<? extends StructField> listFields = structOutputOI.getAllStructFieldRefs();
            for (StructField listField : listFields) {
                if (!hasAllFieldsSettable(listField.getFieldObjectInspector(), oiSettableProperties)) {
                    returnValue = false;
                    break;
                }
            }
            break;
        case LIST:
            ListObjectInspector listOutputOI = (ListObjectInspector) oi;
            returnValue = hasAllFieldsSettable(listOutputOI.getListElementObjectInspector(), oiSettableProperties);
            break;
        case MAP:
            MapObjectInspector mapOutputOI = (MapObjectInspector) oi;
            returnValue = hasAllFieldsSettable(mapOutputOI.getMapKeyObjectInspector(), oiSettableProperties) && hasAllFieldsSettable(mapOutputOI.getMapValueObjectInspector(), oiSettableProperties);
            break;
        case UNION:
            UnionObjectInspector unionOutputOI = (UnionObjectInspector) oi;
            List<ObjectInspector> unionListFields = unionOutputOI.getObjectInspectors();
            for (ObjectInspector listField : unionListFields) {
                if (!hasAllFieldsSettable(listField, oiSettableProperties)) {
                    returnValue = false;
                    break;
                }
            }
            break;
        default:
            throw new RuntimeException("Hive internal error inside hasAllFieldsSettable : " + oi.getTypeName() + " not supported yet.");
    }
    return setOISettablePropertiesMap(oi, oiSettableProperties, returnValue);
}

Example 68 with StructField

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

the class ObjectInspectorUtils method compareTypes.

/**
 * Compares two types identified by the given object inspectors. This method
 * compares the types as follows:
 * <ol>
 * <li>If the given inspectors do not belong to same category, the result is
 * negative.</li>
 * <li>If the given inspectors are for <code>PRIMITIVE</code> type, the result
 * is the comparison of their type names.</li>
 * <li>If the given inspectors are for <code>LIST</code> type, then the result
 * is recursive call to compare the type of list elements.</li>
 * <li>If the given inspectors are <code>MAP</code> type, then the result is a
 * recursive call to compare the map key and value types.</li>
 * <li>If the given inspectors are <code>STRUCT</code> type, then the result
 * is negative if they do not have the same number of fields. If they do have
 * the same number of fields, the result is a recursive call to compare each
 * of the field types.</li>
 * <li>If none of the above, the result is negative.</li>
 * </ol>
 * @param o1
 * @param o2
 * @return true if the given object inspectors represent the same types.
 */
public static boolean compareTypes(ObjectInspector o1, ObjectInspector o2) {
    Category c1 = o1.getCategory();
    Category c2 = o2.getCategory();
    // Return false if categories are not equal
    if (!c1.equals(c2)) {
        return false;
    }
    // If both categories are primitive return the comparison of type names.
    if (c1.equals(Category.PRIMITIVE)) {
        return o1.getTypeName().equals(o2.getTypeName());
    }
    // If lists, recursively compare the list element types
    if (c1.equals(Category.LIST)) {
        ObjectInspector child1 = ((ListObjectInspector) o1).getListElementObjectInspector();
        ObjectInspector child2 = ((ListObjectInspector) o2).getListElementObjectInspector();
        return compareTypes(child1, child2);
    }
    // If maps, recursively compare the key and value types
    if (c1.equals(Category.MAP)) {
        MapObjectInspector mapOI1 = (MapObjectInspector) o1;
        MapObjectInspector mapOI2 = (MapObjectInspector) o2;
        ObjectInspector childKey1 = mapOI1.getMapKeyObjectInspector();
        ObjectInspector childKey2 = mapOI2.getMapKeyObjectInspector();
        if (compareTypes(childKey1, childKey2)) {
            ObjectInspector childVal1 = mapOI1.getMapValueObjectInspector();
            ObjectInspector childVal2 = mapOI2.getMapValueObjectInspector();
            if (compareTypes(childVal1, childVal2)) {
                return true;
            }
        }
        return false;
    }
    // If structs, recursively compare the fields
    if (c1.equals(Category.STRUCT)) {
        StructObjectInspector structOI1 = (StructObjectInspector) o1;
        StructObjectInspector structOI2 = (StructObjectInspector) o2;
        List<? extends StructField> childFieldsList1 = structOI1.getAllStructFieldRefs();
        List<? extends StructField> childFieldsList2 = structOI2.getAllStructFieldRefs();
        if (childFieldsList1 == null && childFieldsList2 == null) {
            return true;
        } else if (childFieldsList1 == null || childFieldsList2 == null) {
            return false;
        } else if (childFieldsList1.size() != childFieldsList2.size()) {
            return false;
        }
        Iterator<? extends StructField> it1 = childFieldsList1.iterator();
        Iterator<? extends StructField> it2 = childFieldsList2.iterator();
        while (it1.hasNext()) {
            StructField field1 = it1.next();
            StructField field2 = it2.next();
            if (!compareTypes(field1.getFieldObjectInspector(), field2.getFieldObjectInspector())) {
                return false;
            }
        }
        return true;
    }
    if (c1.equals(Category.UNION)) {
        UnionObjectInspector uoi1 = (UnionObjectInspector) o1;
        UnionObjectInspector uoi2 = (UnionObjectInspector) o2;
        List<ObjectInspector> ois1 = uoi1.getObjectInspectors();
        List<ObjectInspector> ois2 = uoi2.getObjectInspectors();
        if (ois1 == null && ois2 == null) {
            return true;
        } else if (ois1 == null || ois2 == null) {
            return false;
        } else if (ois1.size() != ois2.size()) {
            return false;
        }
        Iterator<? extends ObjectInspector> it1 = ois1.iterator();
        Iterator<? extends ObjectInspector> it2 = ois2.iterator();
        while (it1.hasNext()) {
            if (!compareTypes(it1.next(), it2.next())) {
                return false;
            }
        }
        return true;
    }
    // Unknown category
    throw new RuntimeException("Unknown category encountered: " + c1);
}

Example 69 with StructField

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

the class ObjectInspectorUtils method compare.

/**
 * Compare two objects with their respective ObjectInspectors.
 * if nullValueOpt is MAXVALUE, treat null as maximum value.
 * if nullValueOpt is MINVALUE, treat null as minimum value.
 */
public static int compare(Object o1, ObjectInspector oi1, Object o2, ObjectInspector oi2, MapEqualComparer mapEqualComparer, NullValueOption nullValueOpt) {
    if (oi1.getCategory() != oi2.getCategory()) {
        return oi1.getCategory().compareTo(oi2.getCategory());
    }
    int nullCmpRtn = -1;
    switch(nullValueOpt) {
        case MAXVALUE:
            nullCmpRtn = 1;
            break;
        case MINVALUE:
            nullCmpRtn = -1;
            break;
    }
    if (o1 == null) {
        return o2 == null ? 0 : nullCmpRtn;
    } else if (o2 == null) {
        return -nullCmpRtn;
    }
    switch(oi1.getCategory()) {
        case PRIMITIVE:
            {
                PrimitiveObjectInspector poi1 = ((PrimitiveObjectInspector) oi1);
                PrimitiveObjectInspector poi2 = ((PrimitiveObjectInspector) oi2);
                if (poi1.getPrimitiveCategory() != poi2.getPrimitiveCategory()) {
                    return poi1.getPrimitiveCategory().compareTo(poi2.getPrimitiveCategory());
                }
                switch(poi1.getPrimitiveCategory()) {
                    case VOID:
                        return 0;
                    case BOOLEAN:
                        {
                            int v1 = ((BooleanObjectInspector) poi1).get(o1) ? 1 : 0;
                            int v2 = ((BooleanObjectInspector) poi2).get(o2) ? 1 : 0;
                            return v1 - v2;
                        }
                    case BYTE:
                        {
                            int v1 = ((ByteObjectInspector) poi1).get(o1);
                            int v2 = ((ByteObjectInspector) poi2).get(o2);
                            return v1 - v2;
                        }
                    case SHORT:
                        {
                            int v1 = ((ShortObjectInspector) poi1).get(o1);
                            int v2 = ((ShortObjectInspector) poi2).get(o2);
                            return v1 - v2;
                        }
                    case INT:
                        {
                            int v1 = ((IntObjectInspector) poi1).get(o1);
                            int v2 = ((IntObjectInspector) poi2).get(o2);
                            return v1 > v2 ? 1 : (v1 < v2 ? -1 : 0);
                        }
                    case LONG:
                        {
                            long v1 = ((LongObjectInspector) poi1).get(o1);
                            long v2 = ((LongObjectInspector) poi2).get(o2);
                            return v1 > v2 ? 1 : (v1 < v2 ? -1 : 0);
                        }
                    case FLOAT:
                        {
                            float v1 = ((FloatObjectInspector) poi1).get(o1);
                            float v2 = ((FloatObjectInspector) poi2).get(o2);
                            // The IEEE 754 floating point spec specifies that signed -0.0 and 0.0 should be treated as equal.
                            if (v1 == 0.0f && v2 == 0.0f) {
                                return 0;
                            } else {
                                // Float.compare() treats -0.0 and 0.0 as different
                                return Float.compare(v1, v2);
                            }
                        }
                    case DOUBLE:
                        {
                            double v1 = ((DoubleObjectInspector) poi1).get(o1);
                            double v2 = ((DoubleObjectInspector) poi2).get(o2);
                            // The IEEE 754 floating point spec specifies that signed -0.0 and 0.0 should be treated as equal.
                            if (v1 == 0.0d && v2 == 0.0d) {
                                return 0;
                            } else {
                                // Double.compare() treats -0.0 and 0.0 as different
                                return Double.compare(v1, v2);
                            }
                        }
                    case STRING:
                        {
                            if (poi1.preferWritable() || poi2.preferWritable()) {
                                Text t1 = (Text) poi1.getPrimitiveWritableObject(o1);
                                Text t2 = (Text) poi2.getPrimitiveWritableObject(o2);
                                return t1 == null ? (t2 == null ? 0 : -1) : (t2 == null ? 1 : t1.compareTo(t2));
                            } else {
                                String s1 = (String) poi1.getPrimitiveJavaObject(o1);
                                String s2 = (String) poi2.getPrimitiveJavaObject(o2);
                                return s1 == null ? (s2 == null ? 0 : -1) : (s2 == null ? 1 : s1.compareTo(s2));
                            }
                        }
                    case CHAR:
                        {
                            HiveCharWritable t1 = ((HiveCharObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            HiveCharWritable t2 = ((HiveCharObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return t1.compareTo(t2);
                        }
                    case VARCHAR:
                        {
                            HiveVarcharWritable t1 = ((HiveVarcharObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            HiveVarcharWritable t2 = ((HiveVarcharObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return t1.compareTo(t2);
                        }
                    case BINARY:
                        {
                            BytesWritable bw1 = ((BinaryObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            BytesWritable bw2 = ((BinaryObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return bw1.compareTo(bw2);
                        }
                    case DATE:
                        {
                            DateWritable d1 = ((DateObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            DateWritable d2 = ((DateObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return d1.compareTo(d2);
                        }
                    case TIMESTAMP:
                        {
                            TimestampWritable t1 = ((TimestampObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            TimestampWritable t2 = ((TimestampObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return t1.compareTo(t2);
                        }
                    case TIMESTAMPLOCALTZ:
                        {
                            TimestampLocalTZWritable tstz1 = ((TimestampLocalTZObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            TimestampLocalTZWritable tstz2 = ((TimestampLocalTZObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return tstz1.compareTo(tstz2);
                        }
                    case INTERVAL_YEAR_MONTH:
                        {
                            HiveIntervalYearMonthWritable i1 = ((HiveIntervalYearMonthObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            HiveIntervalYearMonthWritable i2 = ((HiveIntervalYearMonthObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return i1.compareTo(i2);
                        }
                    case INTERVAL_DAY_TIME:
                        {
                            HiveIntervalDayTimeWritable i1 = ((HiveIntervalDayTimeObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            HiveIntervalDayTimeWritable i2 = ((HiveIntervalDayTimeObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return i1.compareTo(i2);
                        }
                    case DECIMAL:
                        {
                            HiveDecimalWritable t1 = ((HiveDecimalObjectInspector) poi1).getPrimitiveWritableObject(o1);
                            HiveDecimalWritable t2 = ((HiveDecimalObjectInspector) poi2).getPrimitiveWritableObject(o2);
                            return t1.compareTo(t2);
                        }
                    default:
                        {
                            throw new RuntimeException("Unknown type: " + poi1.getPrimitiveCategory());
                        }
                }
            }
        case STRUCT:
            {
                StructObjectInspector soi1 = (StructObjectInspector) oi1;
                StructObjectInspector soi2 = (StructObjectInspector) oi2;
                List<? extends StructField> fields1 = soi1.getAllStructFieldRefs();
                List<? extends StructField> fields2 = soi2.getAllStructFieldRefs();
                int minimum = Math.min(fields1.size(), fields2.size());
                for (int i = 0; i < minimum; i++) {
                    int r = compare(soi1.getStructFieldData(o1, fields1.get(i)), fields1.get(i).getFieldObjectInspector(), soi2.getStructFieldData(o2, fields2.get(i)), fields2.get(i).getFieldObjectInspector(), mapEqualComparer, nullValueOpt);
                    if (r != 0) {
                        return r;
                    }
                }
                return fields1.size() - fields2.size();
            }
        case LIST:
            {
                ListObjectInspector loi1 = (ListObjectInspector) oi1;
                ListObjectInspector loi2 = (ListObjectInspector) oi2;
                int minimum = Math.min(loi1.getListLength(o1), loi2.getListLength(o2));
                for (int i = 0; i < minimum; i++) {
                    int r = compare(loi1.getListElement(o1, i), loi1.getListElementObjectInspector(), loi2.getListElement(o2, i), loi2.getListElementObjectInspector(), mapEqualComparer, nullValueOpt);
                    if (r != 0) {
                        return r;
                    }
                }
                return loi1.getListLength(o1) - loi2.getListLength(o2);
            }
        case MAP:
            {
                if (mapEqualComparer == null) {
                    throw new RuntimeException("Compare on map type not supported!");
                } else {
                    return mapEqualComparer.compare(o1, (MapObjectInspector) oi1, o2, (MapObjectInspector) oi2);
                }
            }
        case UNION:
            {
                UnionObjectInspector uoi1 = (UnionObjectInspector) oi1;
                UnionObjectInspector uoi2 = (UnionObjectInspector) oi2;
                byte tag1 = uoi1.getTag(o1);
                byte tag2 = uoi2.getTag(o2);
                if (tag1 != tag2) {
                    return tag1 - tag2;
                }
                return compare(uoi1.getField(o1), uoi1.getObjectInspectors().get(tag1), uoi2.getField(o2), uoi2.getObjectInspectors().get(tag2), mapEqualComparer, nullValueOpt);
            }
        default:
            throw new RuntimeException("Compare on unknown type: " + oi1.getCategory());
    }
}

Example 70 with StructField

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

the class SerDeUtils method buildJSONString.

static void buildJSONString(StringBuilder sb, Object o, ObjectInspector oi, String nullStr) {
    switch(oi.getCategory()) {
        case PRIMITIVE:
            {
                PrimitiveObjectInspector poi = (PrimitiveObjectInspector) oi;
                if (o == null) {
                    sb.append(nullStr);
                } 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:
                            {
                                sb.append('"');
                                sb.append(escapeString(((StringObjectInspector) poi).getPrimitiveJavaObject(o)));
                                sb.append('"');
                                break;
                            }
                        case CHAR:
                            {
                                sb.append('"');
                                sb.append(escapeString(((HiveCharObjectInspector) poi).getPrimitiveJavaObject(o).toString()));
                                sb.append('"');
                                break;
                            }
                        case VARCHAR:
                            {
                                sb.append('"');
                                sb.append(escapeString(((HiveVarcharObjectInspector) poi).getPrimitiveJavaObject(o).toString()));
                                sb.append('"');
                                break;
                            }
                        case DATE:
                            {
                                sb.append('"');
                                sb.append(((DateObjectInspector) poi).getPrimitiveWritableObject(o));
                                sb.append('"');
                                break;
                            }
                        case TIMESTAMP:
                            {
                                sb.append('"');
                                sb.append(((TimestampObjectInspector) poi).getPrimitiveWritableObject(o));
                                sb.append('"');
                                break;
                            }
                        case TIMESTAMPLOCALTZ:
                            {
                                sb.append('"');
                                sb.append(((TimestampLocalTZObjectInspector) poi).getPrimitiveWritableObject(o));
                                sb.append('"');
                                break;
                            }
                        case BINARY:
                            {
                                BytesWritable bw = ((BinaryObjectInspector) oi).getPrimitiveWritableObject(o);
                                Text txt = new Text();
                                txt.set(bw.getBytes(), 0, bw.getLength());
                                sb.append(txt.toString());
                                break;
                            }
                        case DECIMAL:
                            {
                                sb.append(((HiveDecimalObjectInspector) oi).getPrimitiveJavaObject(o));
                                break;
                            }
                        case INTERVAL_YEAR_MONTH:
                            {
                                sb.append(((HiveIntervalYearMonthObjectInspector) oi).getPrimitiveJavaObject(o));
                                break;
                            }
                        case INTERVAL_DAY_TIME:
                            {
                                sb.append(((HiveIntervalDayTimeObjectInspector) oi).getPrimitiveJavaObject(o));
                                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(nullStr);
                } else {
                    sb.append(LBRACKET);
                    for (int i = 0; i < olist.size(); i++) {
                        if (i > 0) {
                            sb.append(COMMA);
                        }
                        buildJSONString(sb, olist.get(i), listElementObjectInspector, JSON_NULL);
                    }
                    sb.append(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(nullStr);
                } else {
                    sb.append(LBRACE);
                    boolean first = true;
                    for (Object entry : omap.entrySet()) {
                        if (first) {
                            first = false;
                        } else {
                            sb.append(COMMA);
                        }
                        Map.Entry<?, ?> e = (Map.Entry<?, ?>) entry;
                        buildJSONString(sb, e.getKey(), mapKeyObjectInspector, JSON_NULL);
                        sb.append(COLON);
                        buildJSONString(sb, e.getValue(), mapValueObjectInspector, JSON_NULL);
                    }
                    sb.append(RBRACE);
                }
                break;
            }
        case STRUCT:
            {
                StructObjectInspector soi = (StructObjectInspector) oi;
                List<? extends StructField> structFields = soi.getAllStructFieldRefs();
                if (o == null) {
                    sb.append(nullStr);
                } else {
                    sb.append(LBRACE);
                    for (int i = 0; i < structFields.size(); i++) {
                        if (i > 0) {
                            sb.append(COMMA);
                        }
                        sb.append(QUOTE);
                        sb.append(structFields.get(i).getFieldName());
                        sb.append(QUOTE);
                        sb.append(COLON);
                        buildJSONString(sb, soi.getStructFieldData(o, structFields.get(i)), structFields.get(i).getFieldObjectInspector(), JSON_NULL);
                    }
                    sb.append(RBRACE);
                }
                break;
            }
        case UNION:
            {
                UnionObjectInspector uoi = (UnionObjectInspector) oi;
                if (o == null) {
                    sb.append(nullStr);
                } else {
                    sb.append(LBRACE);
                    sb.append(uoi.getTag(o));
                    sb.append(COLON);
                    buildJSONString(sb, uoi.getField(o), uoi.getObjectInspectors().get(uoi.getTag(o)), JSON_NULL);
                    sb.append(RBRACE);
                }
                break;
            }
        default:
            throw new RuntimeException("Unknown type in ObjectInspector!");
    }
}