org.janusgraph.graphdb.database.serialize.attribute

Class StringSerializer

java.lang.Object

org.janusgraph.graphdb.database.serialize.attribute.StringSerializer

All Implemented Interfaces:

AttributeSerializer<String>, OrderPreservingSerializer<String>, SupportsNullSerializer

public class StringSerializer
extends Object
implements OrderPreservingSerializer<String>, SupportsNullSerializer

Serializes Strings by trying to find the most efficient serialization format: 1) ASCII encoding (one byte per char) 2) Full UTF encoding (for non-ASCII strings) 3) Using compression algorithms for long strings

Author:

Matthias Broecheler (me@matthiasb.com)

Field Summary

Fields

Modifier and Type	Field and Description
static int	LONG_COMPRESSION_THRESHOLD
static int	MAX_LENGTH
static int	TEXT_COMPRESSION_THRESHOLD

Constructor Summary

Constructors

Constructor and Description
StringSerializer()

Method Summary

Modifier and Type	Method and Description
String	convert(Object value) Converts the given (not-null) value to the expected data type V.
String	read(ScanBuffer buffer) Reads an attribute from the given ReadBuffer.
String	readByteOrder(ScanBuffer buffer) Reads an attribute from the given ReadBuffer assuming it was written in byte order.
void	verifyAttribute(String value) Verifies the given (not-null) attribute value is valid.
void	write(WriteBuffer buffer, String attribute) Writes the attribute value to the given WriteBuffer.
void	writeByteOrder(WriteBuffer buffer, String attribute) Writes the attribute value to the given WriteBuffer such that the byte order of the result is equal to the natural order of the attribute.

Methods inherited from class java.lang.Object

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

Field Detail

MAX_LENGTH

public static final int MAX_LENGTH

See Also:

Constant Field Values

LONG_COMPRESSION_THRESHOLD

public static final int LONG_COMPRESSION_THRESHOLD

See Also:

Constant Field Values

TEXT_COMPRESSION_THRESHOLD

public static final int TEXT_COMPRESSION_THRESHOLD

See Also:

Constant Field Values

Constructor Detail

StringSerializer

public StringSerializer()

Method Detail

readByteOrder

public String readByteOrder(ScanBuffer buffer)

Description copied from interface: OrderPreservingSerializer

Reads an attribute from the given ReadBuffer assuming it was written in byte order.

It is expected that this read operation adjusts the position in the ReadBuffer to after the attribute value.

Specified by:

readByteOrder in interface OrderPreservingSerializer<String>

Parameters:

buffer - ReadBuffer to read attribute from

Returns:

Read attribute

writeByteOrder

public void writeByteOrder(WriteBuffer buffer,
                           String attribute)

Description copied from interface: OrderPreservingSerializer

Writes the attribute value to the given WriteBuffer such that the byte order of the result is equal to the natural order of the attribute.

It is expected that this write operation adjusts the position in the WriteBuffer to after the attribute value.

Specified by:

writeByteOrder in interface OrderPreservingSerializer<String>

Parameters:

buffer - WriteBuffer to write attribute to

attribute - Attribute to write to WriteBuffer

verifyAttribute

public void verifyAttribute(String value)

Description copied from interface: AttributeSerializer

Verifies the given (not-null) attribute value is valid. Throws an IllegalArgumentException if the value is invalid, otherwise simply returns.

Specified by:

verifyAttribute in interface AttributeSerializer<String>

Parameters:

value - to verify

convert

public String convert(Object value)

Description copied from interface: AttributeSerializer

Converts the given (not-null) value to the expected data type V. The given object will NOT be of type V. Throws an IllegalArgumentException if it cannot be converted.

Specified by:

convert in interface AttributeSerializer<String>

Parameters:

value - to convert

Returns:

converted to expected data type

read

public String read(ScanBuffer buffer)

Description copied from interface: AttributeSerializer

Reads an attribute from the given ReadBuffer.

It is expected that this read operation adjusts the position in the ReadBuffer to after the attribute value.

Specified by:

read in interface AttributeSerializer<String>

Parameters:

buffer - ReadBuffer to read attribute from

Returns:

Read attribute

write

public void write(WriteBuffer buffer,
                  String attribute)

Description copied from interface: AttributeSerializer

Writes the attribute value to the given WriteBuffer.

It is expected that this write operation adjusts the position in the WriteBuffer to after the attribute value.

Specified by:

write in interface AttributeSerializer<String>

Parameters:

buffer - WriteBuffer to write attribute to

attribute - Attribute to write to WriteBuffer