org.apache.jackrabbit.oak.segment

Class SegmentWriter

java.lang.Object

org.apache.jackrabbit.oak.segment.SegmentWriter

public class SegmentWriter
extends Object

A SegmentWriter converts nodes, properties, values, etc. to records and persists them with the help of a WriteOperationHandler. All public methods of this class are thread safe if and only if the WriteOperationHandler passed to the constructor is thread safe.

Constructor Summary

Constructors

Constructor and Description
SegmentWriter(SegmentStore store, SegmentReader reader, org.apache.jackrabbit.oak.spi.blob.BlobStore blobStore, WriterCacheManager cacheManager, org.apache.jackrabbit.oak.segment.WriteOperationHandler writeOperationHandler) Create a new instance of a SegmentWriter.

Method Summary

Modifier and Type	Method and Description
void	flush()
String	getNodeCacheOccupancyInfo() Get occupancy information for the node deduplication cache indicating occupancy and evictions per priority.
org.apache.jackrabbit.oak.api.jmx.CacheStatsMBean	getNodeCacheStats()
org.apache.jackrabbit.oak.api.jmx.CacheStatsMBean	getStringCacheStats()
org.apache.jackrabbit.oak.api.jmx.CacheStatsMBean	getTemplateCacheStats()
void	setCompactionMonitor(GCNodeWriteMonitor compactionMonitor)
SegmentBlob	writeBlob(org.apache.jackrabbit.oak.api.Blob blob) Write a blob (as list of block records)
RecordId	writeBlock(byte[] bytes, int offset, int length) Writes a block record containing the given block of bytes.
RecordId	writeList(List<RecordId> list) Write a list record.
MapRecord	writeMap(MapRecord base, Map<String,RecordId> changes) Write a map record.
SegmentNodeState	writeNode(org.apache.jackrabbit.oak.spi.state.NodeState state) Write a node state.
SegmentNodeState	writeNode(org.apache.jackrabbit.oak.spi.state.NodeState state, com.google.common.base.Supplier<Boolean> cancel) Write a node state, unless cancelled.
SegmentPropertyState	writeProperty(org.apache.jackrabbit.oak.api.PropertyState state) Write a property.
SegmentBlob	writeStream(InputStream stream) Writes a stream value record.
RecordId	writeString(String string) Write a string record.

Methods inherited from class java.lang.Object

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

Constructor Detail

SegmentWriter

public SegmentWriter(@Nonnull
                     SegmentStore store,
                     @Nonnull
                     SegmentReader reader,
                     @Nullable
                     org.apache.jackrabbit.oak.spi.blob.BlobStore blobStore,
                     @Nonnull
                     WriterCacheManager cacheManager,
                     @Nonnull
                     org.apache.jackrabbit.oak.segment.WriteOperationHandler writeOperationHandler)

Create a new instance of a SegmentWriter. Note the thread safety properties pointed out in the class comment.

Parameters:

store - store to write to

reader - segment reader for the store

blobStore - the blog store or null for inlined blobs

cacheManager - cache manager instance for the de-duplication caches used by this writer

writeOperationHandler - handler for write operations.

Method Detail

getNodeCacheOccupancyInfo

@CheckForNull
public String getNodeCacheOccupancyInfo()

Get occupancy information for the node deduplication cache indicating occupancy and evictions per priority.

Returns:

occupancy information for the node deduplication cache.

flush

public void flush()
           throws IOException

Throws:

IOException

getStringCacheStats

@CheckForNull
public org.apache.jackrabbit.oak.api.jmx.CacheStatsMBean getStringCacheStats()

Returns:

Statistics for the string deduplication cache or null if not available.

getTemplateCacheStats

@CheckForNull
public org.apache.jackrabbit.oak.api.jmx.CacheStatsMBean getTemplateCacheStats()

Returns:

Statistics for the template deduplication cache or null if not available.

getNodeCacheStats

@CheckForNull
public org.apache.jackrabbit.oak.api.jmx.CacheStatsMBean getNodeCacheStats()

Returns:

Statistics for the node deduplication cache or null if not available.

writeMap

@Nonnull
public MapRecord writeMap(@Nullable
                                   MapRecord base,
                                   @Nonnull
                                   Map<String,RecordId> changes)
                            throws IOException

Write a map record.

Parameters:

base - base map relative to which the changes are applied ot null for the empty map.

changes - the changed mapping to apply to the base map.

Returns:

the map record written

Throws:

IOException

writeList

@Nonnull
public RecordId writeList(@Nonnull
                                   List<RecordId> list)
                            throws IOException

Write a list record.

Parameters:

list - the list to write.

Returns:

the record id of the list written

Throws:

IOException

writeString

@Nonnull
public RecordId writeString(@Nonnull
                                     String string)
                              throws IOException

Write a string record.

Parameters:

string - the string to write.

Returns:

the record id of the string written.

Throws:

IOException

writeBlob

@Nonnull
public SegmentBlob writeBlob(@Nonnull
                                      org.apache.jackrabbit.oak.api.Blob blob)
                               throws IOException

Write a blob (as list of block records)

Parameters:

blob - blob to write

Returns:

The segment blob written

Throws:

IOException

writeBlock

@Nonnull
public RecordId writeBlock(@Nonnull
                                    byte[] bytes,
                                    int offset,
                                    int length)
                             throws IOException

Writes a block record containing the given block of bytes.

Parameters:

bytes - source buffer

offset - offset within the source buffer

length - number of bytes to write

Returns:

block record identifier

Throws:

IOException

writeStream

@Nonnull
public SegmentBlob writeStream(@Nonnull
                                        InputStream stream)
                                 throws IOException

Writes a stream value record. The given stream is consumed and closed by this method.

Parameters:

stream - stream to be written

Returns:

blob for the passed stream

Throws:

IOException - if the input stream could not be read or the output could not be written

writeProperty

@Nonnull
public SegmentPropertyState writeProperty(@Nonnull
                                                   org.apache.jackrabbit.oak.api.PropertyState state)
                                            throws IOException

Write a property.

Parameters:

state - the property to write

Returns:

the property state written

Throws:

IOException

writeNode

@Nonnull
public SegmentNodeState writeNode(@Nonnull
                                           org.apache.jackrabbit.oak.spi.state.NodeState state)
                                    throws IOException

Write a node state.

Note: the returned SegmentNodeState instance is bound to this SegmentWriter instance. That is, future calls to #builder() return a NodeBuilder that is also bound to the same SegmentWriter instance and uses it for writing any changes. This might not always be desired and callers of this method need to take care not to proliferate this writer through the returned node states beyond the intended bounds.

Parameters:

state - node state to write

Returns:

segment node state equal to state

Throws:

IOException

writeNode

@CheckForNull
public SegmentNodeState writeNode(@Nonnull
                                                org.apache.jackrabbit.oak.spi.state.NodeState state,
                                                @Nonnull
                                                com.google.common.base.Supplier<Boolean> cancel)
                                         throws IOException

Write a node state, unless cancelled.

Note: the returned SegmentNodeState instance is bound to this SegmentWriter instance. That is, future calls to #builder() return a NodeBuilder that is also bound to the same SegmentWriter instance and uses it for writing any changes. This might not always be desired and callers of this method need to take care not to proliferate this writer through the returned node states beyond the intended bounds.

Parameters:

state - node state to write

cancel - supplier to signal cancellation of this write operation

Returns:

segment node state equal to state or null if cancelled.

Throws:

IOException

setCompactionMonitor

public void setCompactionMonitor(@Nonnull
                                 GCNodeWriteMonitor compactionMonitor)