Package io.lettuce.core.codec

Class StringCodec

java.lang.Object

io.lettuce.core.codec.StringCodec

All Implemented Interfaces:

RedisCodec<String,String>, ToByteBufEncoder<String,String>

Direct Known Subclasses:

Utf8StringCodec

public class StringCodec
extends Object
implements RedisCodec<String,String>, ToByteBufEncoder<String,String>

Optimized String codec. This RedisCodec encodes and decodes String keys and values using a specified Charset. It accepts provided buffers so it does not need to allocate buffers during encoding.

Since:

4.3

Author:

Mark Paluch, Dimitris Mandalidis

Field Summary

Fields

Modifier and Type	Field	Description
static StringCodec	ASCII
static StringCodec	UTF8

Constructor Summary

Constructors

Constructor	Description
StringCodec()	Creates a new StringCodec with the default charset.
StringCodec(Charset charset)	Creates a new StringCodec for the given Charset that encodes and decodes keys and values.

Method Summary

Modifier and Type	Method	Description
String	decodeKey(ByteBuffer bytes)	Decode the key output by redis.
String	decodeValue(ByteBuffer bytes)	Decode the value output by redis.
void	encode(String str, ByteBuf target)
ByteBuffer	encodeKey(String key)	Encode the key for output to redis.
void	encodeKey(String key, ByteBuf target)	Encode the key for output to redis.
ByteBuffer	encodeValue(String value)	Encode the value for output to redis.
void	encodeValue(String value, ByteBuf target)	Encode the value for output to redis.
int	estimateSize(Object keyOrValue)	Estimates the size of the resulting byte stream.
boolean	isEstimateExact()	Returns true if ToByteBufEncoder.estimateSize(Object) returns exact size This is used as an optimization to reduce memory allocations when encoding data.

Methods inherited from class java.lang.Object

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

Field Detail

UTF8

public static final StringCodec UTF8

ASCII

public static final StringCodec ASCII

Constructor Detail

StringCodec

public StringCodec()

Creates a new StringCodec with the default charset. The default is determined from the file.encoding system property.

StringCodec

public StringCodec(Charset charset)

Creates a new StringCodec for the given Charset that encodes and decodes keys and values.

Parameters:

charset - must not be null.

Method Detail

encodeKey

public void encodeKey(String key,
                      ByteBuf target)

Description copied from interface: ToByteBufEncoder

Encode the key for output to redis.

Specified by:

encodeKey in interface ToByteBufEncoder<String,String>

Parameters:

key - the key, may be null.

target - the target buffer, must not be null.

estimateSize

public int estimateSize(Object keyOrValue)

Description copied from interface: ToByteBufEncoder

Estimates the size of the resulting byte stream. This method is called for keys and values to estimate the size for the temporary buffer to allocate.

Specified by:

estimateSize in interface ToByteBufEncoder<String,String>

Parameters:

keyOrValue - the key or value, may be null.

Returns:

the estimated number of bytes in the encoded representation.

isEstimateExact

public boolean isEstimateExact()

Description copied from interface: ToByteBufEncoder

Returns true if ToByteBufEncoder.estimateSize(Object) returns exact size This is used as an optimization to reduce memory allocations when encoding data.

Specified by:

isEstimateExact in interface ToByteBufEncoder<String,String>

Returns:

true if ToByteBufEncoder.estimateSize(Object) returns exact size.

encodeValue

public void encodeValue(String value,
                        ByteBuf target)

Description copied from interface: ToByteBufEncoder

Encode the value for output to redis.

Specified by:

encodeValue in interface ToByteBufEncoder<String,String>

Parameters:

value - the value, may be null.

target - the target buffer, must not be null.

decodeKey

public String decodeKey(ByteBuffer bytes)

Description copied from interface: RedisCodec

Decode the key output by redis.

Specified by:

decodeKey in interface RedisCodec<String,String>

Parameters:

bytes - Raw bytes of the key, must not be null.

Returns:

The decoded key, may be null.

decodeValue

public String decodeValue(ByteBuffer bytes)

Description copied from interface: RedisCodec

Decode the value output by redis.

Specified by:

decodeValue in interface RedisCodec<String,String>

Parameters:

bytes - Raw bytes of the value, must not be null.

Returns:

The decoded value, may be null.

encodeKey

public ByteBuffer encodeKey(String key)

Description copied from interface: RedisCodec

Encode the key for output to redis.

Specified by:

encodeKey in interface RedisCodec<String,String>

Parameters:

key - the key, may be null.

Returns:

The encoded key, never null.

encodeValue

public ByteBuffer encodeValue(String value)

Description copied from interface: RedisCodec

Encode the value for output to redis.

Specified by:

encodeValue in interface RedisCodec<String,String>

Parameters:

value - the value, may be null.

Returns:

The encoded value, never null.

encode

public void encode(String str,
                   ByteBuf target)