Package io.trino.hive.formats.line.json

Class JsonDeserializer

java.lang.Object

io.trino.hive.formats.line.json.JsonDeserializer

All Implemented Interfaces:

LineDeserializer

public class JsonDeserializer
extends Object
implements LineDeserializer

Deserializer that is bug for bug compatible with Hive JsonSerDe where possible. Known exceptions are:

• When a scalar value is actually a json object, Hive will process the open curly bracket for BOOLEAN, DECIMAL, CHAR, VARCHAR, and VARBINARY. Then it continues processing field inside of the json object as if they are part of the outer json object. When the closing curly bracket is encountered it pops a level, which can end parsing early. This is clearly a bug resulting in corrupted data, and instead we throw an exception.
• Duplicate json object fields are supported, and like Hive. Hive parses each of these duplicate values, but this code only process the last value. This means if one of the duplicates is invalid, Hive will fail, and this code will not.

Field Summary

Fields inherited from interface io.trino.hive.formats.line.LineDeserializer

EMPTY_LINE_DESERIALIZER

Constructor Summary

Constructors

Constructor	Description
JsonDeserializer(List<Column> columns, List<String> timestampFormats)

Method Summary

Modifier and Type	Method	Description
void	deserialize(LineBuffer lineBuffer, PageBuilder builder)	Deserialize the line into the page builder.
List<Type>	getTypes()	Required types for the deserialize page builder.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

JsonDeserializer

public JsonDeserializer(List<Column> columns,
 List<String> timestampFormats)

Method Details

getTypes

public List<Type> getTypes()

Description copied from interface: LineDeserializer

Required types for the deserialize page builder.

Specified by:

getTypes in interface LineDeserializer

deserialize

public void deserialize(LineBuffer lineBuffer,
 PageBuilder builder)
                 throws IOException

Description copied from interface: LineDeserializer

Deserialize the line into the page builder. The implementation will declare the added positions in the page builder. The implementation is allowed to add zero or more positions to the builder.

Specified by:

deserialize in interface LineDeserializer

Parameters:

lineBuffer - the line which may be empty

builder - page builder for the declared types

Throws:

IOException - if line can not be decoded and processing should stop