Package io.deephaven.util.codec

Class MapCodec<K,V>

java.lang.Object

io.deephaven.util.codec.MapCodec<K,V>

All Implemented Interfaces:

ObjectCodec<Map<K,V>>, ObjectDecoder<Map<K,V>>

Direct Known Subclasses:

StringBooleanMapCodec, StringDoubleMapCodec, StringFloatMapCodec, StringIntMapCodec, StringLongMapCodec, StringStringMapCodec

public abstract class MapCodec<K,V>
extends Object
implements ObjectCodec<Map<K,V>>

ObjectCodec implementation for Maps of type K to V. Each map is encoded as an integer length, followed by encoded pairs of key values. A null map is represented as an array of zero bytes.

Field Summary

Fields inherited from interface io.deephaven.util.codec.ObjectDecoder

VARIABLE_WIDTH_SENTINEL

Method Summary

Modifier and Type	Method	Description
@Nullable Map<K,V>	decode(byte @NotNull [] input, int offset, int length)	Decode an object from an array of bytes.
@Nullable Map<K,V>	decode(@NotNull ByteBuffer byteBuffer)	Decode an object from a ByteBuffer.
byte @NotNull []	encode(@Nullable Map<K,V> input)	Encode the specified input as an array of bytes.
int	expectedObjectWidth()	What width byte array does this ObjectCodec expect to encode and decode?
int	getPrecision()	If applicable, the maximum encodable precision.
int	getScale()	If applicable, the maximum encodable scale.
boolean	isNullable()	Does this codec support encoding of null values?

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.deephaven.util.codec.ObjectDecoder

checkWidth

Method Details

isNullable

public boolean isNullable()

Description copied from interface: ObjectCodec

Does this codec support encoding of null values?

Specified by:

isNullable in interface ObjectCodec<K>

Returns:

if null values are supported

getPrecision

public int getPrecision()

Description copied from interface: ObjectCodec

If applicable, the maximum encodable precision. If precision is not applicable (i.e. for non-numeric types) this method should return zero.

Specified by:

getPrecision in interface ObjectCodec<K>

Returns:

the numeric precision supported by this codec

getScale

public int getScale()

Description copied from interface: ObjectCodec

If applicable, the maximum encodable scale. If scale is not applicable (i.e. for non-numeric types) this method should return zero.

Specified by:

getScale in interface ObjectCodec<K>

Returns:

the numeric scale (digits after the decimal point) supported by this codec

encode

public byte @NotNull [] encode(@Nullable
 @Nullable Map<K,V> input)

Description copied from interface: ObjectCodec

Encode the specified input as an array of bytes. Note that it is up to the implementation how to encode null inputs. The use of a zero-length byte array is strongly encouraged.

Specified by:

encode in interface ObjectCodec<K>

Parameters:

input - The input object, possibly null

Returns:

The output byte array

decode

@Nullable
public @Nullable Map<K,V> decode(@NotNull
 @NotNull ByteBuffer byteBuffer)

Description copied from interface: ObjectDecoder

Decode an object from a ByteBuffer. The position of the input buffer may or may not be modified by this method.

Specified by:

decode in interface ObjectDecoder<K>

Parameters:

byteBuffer - The input ByteBuffer containing bytes to decode

Returns:

The output object, possibly null

decode

@Nullable
public @Nullable Map<K,V> decode(byte @NotNull [] input,
 int offset,
 int length)

Description copied from interface: ObjectDecoder

Decode an object from an array of bytes.

Specified by:

decode in interface ObjectDecoder<K>

Parameters:

input - The input byte array containing bytes to decode

offset - The offset into the byte array to start decoding from

length - The number of bytes to decode, starting at the offset

Returns:

The output object, possibly null

expectedObjectWidth

public int expectedObjectWidth()

Description copied from interface: ObjectDecoder

What width byte array does this ObjectCodec expect to encode and decode?

Specified by:

expectedObjectWidth in interface ObjectDecoder<K>

Returns:

VARIABLE_WIDTH_SENTINEL if the codec must encode and decode variable width columns, otherwise the fixed size of byte array that must be decoded and encoded.