Class PrefixedStringEncoder

java.lang.Object

org.apache.mina.filter.codec.ProtocolEncoderAdapter

org.apache.mina.filter.codec.prefixedstring.PrefixedStringEncoder

All Implemented Interfaces:

ProtocolEncoder

public class PrefixedStringEncoder
extends ProtocolEncoderAdapter

A ProtocolEncoder which encodes a string using a fixed-length length prefix.

Field Summary

Fields

Modifier and Type	Field	Description
private final Charset	charset
static final int	DEFAULT_MAX_DATA_LENGTH	The default maximum data length
static final int	DEFAULT_PREFIX_LENGTH	The default length for the prefix
private int	maxDataLength
private int	prefixLength

Constructor Summary

Constructors

Constructor	Description
PrefixedStringEncoder()	Creates a new PrefixedStringEncoder instance
PrefixedStringEncoder(Charset charset)	Creates a new PrefixedStringEncoder instance
PrefixedStringEncoder(Charset charset, int prefixLength)	Creates a new PrefixedStringEncoder instance
PrefixedStringEncoder(Charset charset, int prefixLength, int maxDataLength)	Creates a new PrefixedStringEncoder instance

Method Summary

Modifier and Type	Method	Description
void	encode(IoSession session, Object message, ProtocolEncoderOutput out)	Encodes higher-level message objects into binary or protocol-specific data.
int	getMaxDataLength()	Gets the maximum number of bytes allowed for encoding a single String *
int	getPrefixLength()	Gets the length of the length prefix (1, 2, or 4)
void	setMaxDataLength(int maxDataLength)	Sets the maximum number of bytes allowed for encoding a single String (including the prefix)
void	setPrefixLength(int prefixLength)	Sets the number of bytes used by the length prefix

Methods inherited from class ProtocolEncoderAdapter

dispose

Methods inherited from class Object

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

Field Details

DEFAULT_PREFIX_LENGTH

public static final int DEFAULT_PREFIX_LENGTH

The default length for the prefix

See Also:

• Constant Field Values

DEFAULT_MAX_DATA_LENGTH

public static final int DEFAULT_MAX_DATA_LENGTH

The default maximum data length

See Also:

• Constant Field Values

charset

private final Charset charset

prefixLength

private int prefixLength

maxDataLength

private int maxDataLength

Constructor Details

PrefixedStringEncoder

public PrefixedStringEncoder(Charset charset,
 int prefixLength,
 int maxDataLength)

Creates a new PrefixedStringEncoder instance

Parameters:

charset - the Charset to use for encoding

prefixLength - the length of the prefix

maxDataLength - maximum number of bytes allowed for a single String

PrefixedStringEncoder

public PrefixedStringEncoder(Charset charset,
 int prefixLength)

Creates a new PrefixedStringEncoder instance

Parameters:

charset - the Charset to use for encoding

prefixLength - the length of the prefix

PrefixedStringEncoder

public PrefixedStringEncoder(Charset charset)

Creates a new PrefixedStringEncoder instance

Parameters:

charset - the Charset to use for encoding

PrefixedStringEncoder

public PrefixedStringEncoder()

Creates a new PrefixedStringEncoder instance

Method Details

setPrefixLength

public void setPrefixLength(int prefixLength)

Sets the number of bytes used by the length prefix

Parameters:

prefixLength - the length of the length prefix (1, 2, or 4)

getPrefixLength

public int getPrefixLength()

Gets the length of the length prefix (1, 2, or 4)

Returns:

length of the length prefix

setMaxDataLength

public void setMaxDataLength(int maxDataLength)

Sets the maximum number of bytes allowed for encoding a single String (including the prefix)

The encoder will throw a IllegalArgumentException when more bytes are needed to encode a String value. The default value is DEFAULT_MAX_DATA_LENGTH.

Parameters:

maxDataLength - maximum number of bytes allowed for encoding a single String

getMaxDataLength

public int getMaxDataLength()

Gets the maximum number of bytes allowed for encoding a single String *

Returns:

maximum number of bytes allowed for encoding a single String (prefix included)

encode

public void encode(IoSession session,
 Object message,
 ProtocolEncoderOutput out)
            throws Exception

Encodes higher-level message objects into binary or protocol-specific data. MINA invokes ProtocolEncoder.encode(IoSession, Object, ProtocolEncoderOutput) method with message which is popped from the session write queue, and then the encoder implementation puts encoded messages (typically IoBuffers) into ProtocolEncoderOutput.

Parameters:

session - The current Session

message - the message to encode

out - The ProtocolEncoderOutput that will receive the encoded message

Throws:

Exception - if the message violated protocol specification