Package it.unimi.dsi.webgraph.labelling

Class FixedWidthIntListLabel

java.lang.Object

it.unimi.dsi.webgraph.labelling.AbstractLabel

it.unimi.dsi.webgraph.labelling.AbstractIntListLabel

it.unimi.dsi.webgraph.labelling.FixedWidthIntListLabel

All Implemented Interfaces:

FlyweightPrototype<Label>, Label

public class FixedWidthIntListLabel
extends AbstractIntListLabel

A list of integers represented in fixed width. The provided width must be smaller than 32. Each list is prefixed by its length written in γ coding.

Field Summary

Fields inherited from class it.unimi.dsi.webgraph.labelling.AbstractIntListLabel

key, value

Fields inherited from interface it.unimi.dsi.webgraph.labelling.Label

EMPTY_LABEL_ARRAY

Constructor Summary

Constructors

Constructor	Description
FixedWidthIntListLabel(String... arg)	Creates a new fixed-width integer label using the given key and width with an empty list.
FixedWidthIntListLabel(String key, int width)	Creates a new fixed-width label with an empty list.
FixedWidthIntListLabel(String key, int width, int[] value)	Creates a new fixed-width int label.

Method Summary

Modifier and Type	Method	Description
Label	copy()	Returns a copy of this label.
int	fixedWidth()	Returns -1 (the fixed width refers to a single integer, not to the entire list).
int	fromBitStream(InputBitStream inputBitStream, int sourceUnused)	Fills this label with data from the given input bit stream, knowing the source node of the arc.
int	toBitStream(OutputBitStream outputBitStream, int sourceUnused)	Writes out this label to the given input bit stream, in self-delimiting form, knowing the source node of the arc.
String	toSpec()	Returns a string representing the specification of this label.
String	toString()

Methods inherited from class it.unimi.dsi.webgraph.labelling.AbstractIntListLabel

attributeKeys, attributeTypes, equals, get, get, hashCode, wellKnownAttributeKey

Methods inherited from class it.unimi.dsi.webgraph.labelling.AbstractLabel

getBoolean, getBoolean, getByte, getByte, getChar, getChar, getDouble, getDouble, getFloat, getFloat, getInt, getInt, getLong, getLong, getShort, getShort

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface it.unimi.dsi.webgraph.labelling.Label

getBoolean, getBoolean, getByte, getByte, getChar, getChar, getDouble, getDouble, getFloat, getFloat, getInt, getInt, getLong, getLong, getShort, getShort

Constructor Details

FixedWidthIntListLabel

public FixedWidthIntListLabel(String key,
int width,
int[] value)

Creates a new fixed-width int label.

Parameters:

key - the (only) key of this label.

width - the label width (in bits).

value - the value of this label.

FixedWidthIntListLabel

public FixedWidthIntListLabel(String key,
int width)

Creates a new fixed-width label with an empty list.

Parameters:

key - the (only) key of this label.

width - the label width (in bits).

FixedWidthIntListLabel

public FixedWidthIntListLabel(String... arg)

Creates a new fixed-width integer label using the given key and width with an empty list.

Parameters:

arg - two strings containing the key and the width of this label.

Method Details

copy

public Label copy()

Description copied from interface: Label

Returns a copy of this label.

Returns:

a new label that copies this one.

fromBitStream

public int fromBitStream(InputBitStream inputBitStream,
int sourceUnused)
                  throws IOException

Description copied from interface: Label

Fills this label with data from the given input bit stream, knowing the source node of the arc. If Label.fixedWidth() is not negative, the value returned must coincide with Label.fixedWidth(). This method is optional.

Parameters:

inputBitStream - an input bit stream offering a label.

sourceUnused - the source node.

Returns:

the number of bits read to fill this label.

Throws:

IOException

toBitStream

public int toBitStream(OutputBitStream outputBitStream,
int sourceUnused)
                throws IOException

Description copied from interface: Label

Writes out this label to the given input bit stream, in self-delimiting form, knowing the source node of the arc. If Label.fixedWidth() is not negative, the value returned must coincide with Label.fixedWidth(). This method is optional.

Parameters:

outputBitStream - an output bit stream where the label will be written.

sourceUnused - the source node.

Returns:

the number of bits written.

Throws:

IOException

fixedWidth

public int fixedWidth()

Returns -1 (the fixed width refers to a single integer, not to the entire list).

Returns:

-1;

toString

public String toString()

Overrides:

toString in class AbstractIntListLabel

toSpec

public String toSpec()

Description copied from interface: Label

Returns a string representing the specification of this label.

Each label class can be instantiated in several ways (e.g., FixedWidthIntLabel requires a name for the well-known attribute and a number of bits). This method must return a representation that can be used by ObjectParser to instantiate the class, and consequently there must exist a matching constructor whose arguments are strings.

There is an equation that must be always satisfied:

 ObjectParser.fromSpec(x.toSpec()).toSpec().equals(x.toSpec())
 

Returns:

a string representing the specification of this label.

See Also:

ObjectParser.fromSpec(String, Class)