Package org.apache.jackrabbit.oak.segment

Class CachingSegmentReader

java.lang.Object

org.apache.jackrabbit.oak.segment.CachingSegmentReader

All Implemented Interfaces:

SegmentReader

public class CachingSegmentReader
extends Object
implements SegmentReader

This SegmentReader implementation implements caching for strings and templates. It can also optionally rely on a BlobStore for resolving blobs.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_STRING_CACHE_MB
static final int	DEFAULT_TEMPLATE_CACHE_MB

Constructor Summary

Constructors

Constructor	Description
CachingSegmentReader(@NotNull Supplier<SegmentWriter> writer, @Nullable BlobStore blobStore, long stringCacheMB, long templateCacheMB, MeterStats readStats)	Create a new instance based on the supplied arguments.

Method Summary

Modifier and Type	Method	Description
@NotNull CacheStats	getStringCacheStats()
@NotNull CacheStats	getTemplateCacheStats()
@NotNull SegmentBlob	readBlob(@NotNull RecordId id)	Read the blob identified by id.
@NotNull SegmentNodeState	readHeadState(@NotNull Revisions revisions)	Read the current head state based on the head of revisions
@NotNull MapRecord	readMap(@NotNull RecordId id)	Read the map identified by id.
@NotNull SegmentNodeState	readNode(@NotNull RecordId id)	Read the node identified by id.
@NotNull SegmentPropertyState	readProperty(@NotNull RecordId id, @NotNull PropertyTemplate template)	Read the property identified by id and template
@NotNull String	readString(@NotNull RecordId id)	Cached reading of a string.
@NotNull Template	readTemplate(@NotNull RecordId id)	Cached reading of a template.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_STRING_CACHE_MB

public static final int DEFAULT_STRING_CACHE_MB

See Also:

• Constant Field Values

DEFAULT_TEMPLATE_CACHE_MB

public static final int DEFAULT_TEMPLATE_CACHE_MB

See Also:

• Constant Field Values

Constructor Details

CachingSegmentReader

public CachingSegmentReader(@NotNull
 @NotNull Supplier<SegmentWriter> writer,
 @Nullable
 @Nullable BlobStore blobStore,
 long stringCacheMB,
 long templateCacheMB,
 MeterStats readStats)

Create a new instance based on the supplied arguments.

Parameters:

writer - A Supplier for a the SegmentWriter used by the segment builders returned from NodeState.builder() to write ahead changes. writer.get() must not return null.

blobStore - BlobStore instance of the underlying SegmentStore, or null if none.

stringCacheMB - the size of the string cache in MBs or 0 for no cache.

templateCacheMB - the size of the template cache in MBs or 0 for no cache.

Method Details

readString

@NotNull
public @NotNull String readString(@NotNull
 @NotNull RecordId id)

Cached reading of a string.

Specified by:

readString in interface SegmentReader

readMap

@NotNull
public @NotNull MapRecord readMap(@NotNull
 @NotNull RecordId id)

Description copied from interface: SegmentReader

Read the map identified by id.

Specified by:

readMap in interface SegmentReader

readTemplate

@NotNull
public @NotNull Template readTemplate(@NotNull
 @NotNull RecordId id)

Cached reading of a template.

Specified by:

readTemplate in interface SegmentReader

readNode

@NotNull
public @NotNull SegmentNodeState readNode(@NotNull
 @NotNull RecordId id)

Description copied from interface: SegmentReader

Read the node identified by id.

Specified by:

readNode in interface SegmentReader

readHeadState

@NotNull
public @NotNull SegmentNodeState readHeadState(@NotNull
 @NotNull Revisions revisions)

Description copied from interface: SegmentReader

Read the current head state based on the head of revisions

Specified by:

readHeadState in interface SegmentReader

readProperty

@NotNull
public @NotNull SegmentPropertyState readProperty(@NotNull
 @NotNull RecordId id,
 @NotNull
 @NotNull PropertyTemplate template)

Description copied from interface: SegmentReader

Read the property identified by id and template

Specified by:

readProperty in interface SegmentReader

readBlob

@NotNull
public @NotNull SegmentBlob readBlob(@NotNull
 @NotNull RecordId id)

Description copied from interface: SegmentReader

Read the blob identified by id.

Specified by:

readBlob in interface SegmentReader

getStringCacheStats

@NotNull
public @NotNull CacheStats getStringCacheStats()

getTemplateCacheStats

@NotNull
public @NotNull CacheStats getTemplateCacheStats()