Package io.github.jbellis.jvector.graph.disk

Class OnDiskGraphIndexWriter

java.lang.Object

io.github.jbellis.jvector.graph.disk.OnDiskGraphIndexWriter

All Implemented Interfaces:

Closeable, AutoCloseable

public class OnDiskGraphIndexWriter
extends Object
implements Closeable

Write a graph index to disk, for later loading as an OnDiskGraphIndex.

Implements `getFeatureSource` to allow incremental construction of a larger-than-memory graph (using the writer as the source of INLINE_VECTORS or LVQ).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	OnDiskGraphIndexWriter.Builder	Builder for OnDiskGraphIndexWriter, with optional features.
static class	OnDiskGraphIndexWriter.IdentityMapper
static interface	OnDiskGraphIndexWriter.OrdinalMapper

Method Summary

Modifier and Type	Method	Description
long	checksum()	CRC32 checksum of bytes written since the starting offset
void	close()
FeatureSource	getFeatureSource()
int	getMaxOrdinal()
BufferedRandomAccessWriter	getOutput()
static Map<Integer,Integer>	sequentialRenumbering(GraphIndex graph)
void	write(Map<FeatureId,IntFunction<Feature.State>> featureStateSuppliers)	Write the complete index to the given output.
void	writeInline(int ordinal, Map<FeatureId,Feature.State> stateMap)	Write the inline features of the given ordinal to the output at the correct offset.

Methods inherited from class java.lang.Object

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

Method Details

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

getOutput

public BufferedRandomAccessWriter getOutput()

writeInline

public void writeInline(int ordinal,
 Map<FeatureId,Feature.State> stateMap)
                 throws IOException

Write the inline features of the given ordinal to the output at the correct offset. Nothing else is written (no headers, no edges).

Throws:

IOException

getMaxOrdinal

public int getMaxOrdinal()

getFeatureSource

public FeatureSource getFeatureSource()

write

public void write(Map<FeatureId,IntFunction<Feature.State>> featureStateSuppliers)
           throws IOException

Write the complete index to the given output. Features that do not have a supplier are assumed to have already been written by calls to writeInline. The supplier takes node ordinals and returns FeatureState suitable for Feature.writeInline.

Throws:

IOException

sequentialRenumbering

public static Map<Integer,Integer> sequentialRenumbering(GraphIndex graph)

Returns:

a Map of old to new graph ordinals where the new ordinals are sequential starting at 0, while preserving the original relative ordering in `graph`. That is, for all node ids i and j, if i < j in `graph` then map[i] < map[j] in the returned map. "Holes" left by deleted nodes are filled in by shifting down the new ordinals.

checksum

public long checksum()
              throws IOException

CRC32 checksum of bytes written since the starting offset

Throws:

IOException