Store

java.lang.Object
- org.elasticsearch.index.shard.AbstractIndexShardComponent
- - org.elasticsearch.index.store.Store

All Implemented Interfaces:

Closeable, AutoCloseable, RefCounted, CloseableIndexComponent, IndexShardComponent
```
public class Store
extends AbstractIndexShardComponent
implements CloseableIndexComponent, Closeable, RefCounted
```
A Store provides plain access to files written by an elasticsearch index shard. Each shard has a dedicated store that is uses to access Lucene's Directory which represents the lowest level of file abstraction in Lucene used to read and write Lucene indices. This class also provides access to metadata information like checksums for committed files. A committed file is a file that belongs to a segment written by a Lucene commit. Files that have not been committed ie. created during a merge or a shard refresh / NRT reopen are not considered in the MetadataSnapshot.
Note: If you use a store it's reference count should be increased before using it by calling #incRef and a corresponding #decRef must be called in a try/finally block to release the store again ie.:
```
      store.incRef();
      try {
        // use the store...

      } finally {
          store.decRef();
      }
 
```

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
`static class`	`Store.LegacyChecksums`
`static class`	`Store.MetadataSnapshot` Represents a snapshot of the current directory build from the latest Lucene commit.
`static interface`	`Store.OnClose` A listener that is executed once the store is closed and all references to it are released
`static class`	`Store.RecoveryDiff` A class representing the diff between a recovery source and recovery target
`class`	`Store.StoreDirectory` This exists so `BloomFilterPostingsFormat` can load its boolean setting; can we find a more straightforward way?

Field Summary

Fields

Modifier and Type	Field and Description
`static String`	`CHECKSUMS_PREFIX`
`static String`	`INDEX_STORE_STATS_REFRESH_INTERVAL`

Fields inherited from class org.elasticsearch.index.shard.AbstractIndexShardComponent
componentSettings, indexSettings, logger, shardId

Constructor Summary

Constructors

Constructor and Description
`Store(ShardId shardId, Settings indexSettings, DirectoryService directoryService, Distributor distributor, ShardLock shardLock)`
`Store(ShardId shardId, Settings indexSettings, DirectoryService directoryService, Distributor distributor, ShardLock shardLock, Store.OnClose onClose)`

Method Summary

All Methods

Static Methods

Instance Methods

Concrete Methods
Modifier and Type	Method and Description
`static boolean`	`canOpenIndex(ESLogger logger, File... indexLocations)` Returns `true` iff the given location contains an index an the index can be successfully opened.
`boolean`	`checkIntegrity(StoreFileMetaData md)`
`static boolean`	`checkIntegrity(StoreFileMetaData md, org.apache.lucene.store.Directory directory)`
`void`	`cleanup(String reason, Set<String> filesToClean)` This method deletes every file in this store that is not contained in the given source meta data or is a legacy checksum file.
`void`	`cleanupAndVerify(String reason, Store.MetadataSnapshot sourceMetaData)` This method deletes every file in this store that is not contained in the given source meta data or is a legacy checksum file.
`void`	`close()` Closes the index component.
`org.apache.lucene.store.IndexOutput`	`createVerifyingOutput(String fileName, StoreFileMetaData metadata, org.apache.lucene.store.IOContext context)` The returned IndexOutput might validate the files checksum if the file has been written with a newer lucene version and the metadata holds the necessary information to detect that it was been written by Lucene 4.8 or newer.
`void`	`decRef()` Decreases the refCount of this Store instance.If the refCount drops to 0, then this store is closed.
`void`	`deleteQuiet(String... files)`
`static String`	`digestToString(long digest)` Produces a string representation of the given digest value.
`org.apache.lucene.store.Directory`	`directory()`
`void`	`failIfCorrupted()`
`Store.MetadataSnapshot`	`getMetadata()` Returns a new MetadataSnapshot for the latest commit in this store.
`Store.MetadataSnapshot`	`getMetadata(org.apache.lucene.index.IndexCommit commit)` Returns a new MetadataSnapshot for the given commit.
`Store.MetadataSnapshot`	`getMetadataOrEmpty()` Returns a new MetadataSnapshot for the latest commit in this store or an empty snapshot if no index exists or can not be opened.
`void`	`incRef()` Increments the refCount of this Store instance.
`static boolean`	`isChecksum(String name)`
`boolean`	`isMarkedCorrupted()`
`static void`	`logDeleteFile(org.apache.lucene.store.Directory dir, String message, String fileName)` Log that we are about to delete this file, to the index.store.deletes component.
`void`	`logDeleteFile(String message, String fileName)` Log that we are about to delete this file, to the index.store.deletes component.
`void`	`markStoreCorrupted(IOException exception)` Marks this store as corrupted.
`org.apache.lucene.store.IndexInput`	`openVerifyingInput(String filename, org.apache.lucene.store.IOContext context, StoreFileMetaData metadata)`
`org.apache.lucene.index.SegmentInfos`	`readLastCommittedSegmentsInfo()` Returns the last committed segments info for this store
`static Store.MetadataSnapshot`	`readMetadataSnapshot(File[] indexLocations, ESLogger logger)` Reads a MetadataSnapshot from the given index locations or returns an empty snapshot if it can't be read.
`int`	`refCount()` Returns the current reference count.
`void`	`removeCorruptionMarker()` Deletes all corruption markers from this store.
`void`	`renameFile(String from, String to)`
`void`	`renameTempFilesSafe(Map<String,String> tempFileMap)` Renames all the given files form the key of the map to the value of the map.
`StoreStats`	`stats()`
`boolean`	`tryIncRef()` Tries to increment the refCount of this Store instance.
`static void`	`verify(org.apache.lucene.store.IndexInput input)`
`static void`	`verify(org.apache.lucene.store.IndexOutput output)`

Methods inherited from class org.elasticsearch.index.shard.AbstractIndexShardComponent
indexSettings, nodeName, shardId

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - INDEX_STORE_STATS_REFRESH_INTERVAL
```
public static final String INDEX_STORE_STATS_REFRESH_INTERVAL
```
    See Also:
    
    Constant Field Values
  - CHECKSUMS_PREFIX
```
public static final String CHECKSUMS_PREFIX
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Store
```
public Store(ShardId shardId,
             @IndexSettings
             Settings indexSettings,
             DirectoryService directoryService,
             Distributor distributor,
             ShardLock shardLock)
      throws IOException
```
    Throws:
    
    IOException
  - Store
```
@Inject
public Store(ShardId shardId,
                     @IndexSettings
                     Settings indexSettings,
                     DirectoryService directoryService,
                     Distributor distributor,
                     ShardLock shardLock,
                     Store.OnClose onClose)
              throws IOException
```
    Throws:
    
    IOException
- Method Detail
  - directory
```
public org.apache.lucene.store.Directory directory()
```
  - readLastCommittedSegmentsInfo
```
public org.apache.lucene.index.SegmentInfos readLastCommittedSegmentsInfo()
                                                                   throws IOException
```
    Returns the last committed segments info for this store
    
    Throws:
    
    IOException - if the index is corrupted or the segments file is not present
  - getMetadataOrEmpty
```
public Store.MetadataSnapshot getMetadataOrEmpty()
                                          throws IOException
```
    Returns a new MetadataSnapshot for the latest commit in this store or an empty snapshot if no index exists or can not be opened.
    
    Throws:
    
    org.apache.lucene.index.CorruptIndexException - if the lucene index is corrupted. This can be caused by a checksum mismatch or an unexpected exception when opening the index reading the segments file.
    
    IOException
  - getMetadata
```
public Store.MetadataSnapshot getMetadata()
                                   throws IOException
```
    Returns a new MetadataSnapshot for the latest commit in this store.
    
    Throws:
    
    org.apache.lucene.index.CorruptIndexException - if the lucene index is corrupted. This can be caused by a checksum mismatch or an unexpected exception when opening the index reading the segments file.
    
    FileNotFoundException - if one or more files referenced by a commit are not present.
    
    NoSuchFileException - if one or more files referenced by a commit are not present.
    
    org.apache.lucene.index.IndexNotFoundException - if no index / valid commit-point can be found in this store
    
    IOException
  - getMetadata
```
public Store.MetadataSnapshot getMetadata(org.apache.lucene.index.IndexCommit commit)
                                   throws IOException
```
    Returns a new MetadataSnapshot for the given commit. If the given commit is null the latest commit point is used.
    
    Throws:
    
    org.apache.lucene.index.CorruptIndexException - if the lucene index is corrupted. This can be caused by a checksum mismatch or an unexpected exception when opening the index reading the segments file.
    
    FileNotFoundException - if one or more files referenced by a commit are not present.
    
    NoSuchFileException - if one or more files referenced by a commit are not present.
    
    org.apache.lucene.index.IndexNotFoundException - if the commit point can't be found in this store
    
    IOException
  - renameTempFilesSafe
```
public void renameTempFilesSafe(Map<String,String> tempFileMap)
                         throws IOException
```
    Renames all the given files form the key of the map to the value of the map. All successfully renamed files are removed from the map in-place.
    
    Throws:
    
    IOException
  - stats
```
public StoreStats stats()
                 throws IOException
```
    Throws:
    
    IOException
  - renameFile
```
public void renameFile(String from,
                       String to)
                throws IOException
```
    Throws:
    
    IOException
  - incRef
```
public final void incRef()
```
    Increments the refCount of this Store instance. RefCounts are used to determine when a Store can be closed safely, i.e. as soon as there are no more references. Be sure to always call a corresponding decRef(), in a finally clause; otherwise the store may never be closed. Note that close() simply calls decRef(), which means that the Store will not really be closed until decRef() has been called for all outstanding references.
    Note: Close can safely be called multiple times.
    
    Specified by:
    
    incRef in interface RefCounted
    
    Throws:
    
    org.apache.lucene.store.AlreadyClosedException - iff the reference counter can not be incremented.
    
    See Also:
    
    decRef(), tryIncRef()
  - tryIncRef
```
public final boolean tryIncRef()
```
    Tries to increment the refCount of this Store instance. This method will return true iff the refCount was incremented successfully otherwise false. RefCounts are used to determine when a Store can be closed safely, i.e. as soon as there are no more references. Be sure to always call a corresponding decRef(), in a finally clause; otherwise the store may never be closed. Note that close() simply calls decRef(), which means that the Store will not really be closed until decRef() has been called for all outstanding references.
    Note: Close can safely be called multiple times.
    
    Specified by:
    
    tryIncRef in interface RefCounted
    
    See Also:
    
    decRef(), incRef()
  - decRef
```
public final void decRef()
```
    Decreases the refCount of this Store instance.If the refCount drops to 0, then this store is closed.
    
    Specified by:
    
    decRef in interface RefCounted
    
    See Also:
    
    incRef()
  - close
```
public void close()
```
    Description copied from interface: CloseableIndexComponent
    
    Closes the index component. A boolean indicating if its part of an actual index deletion or not is passed.
  - readMetadataSnapshot
```
public static Store.MetadataSnapshot readMetadataSnapshot(File[] indexLocations,
                                                          ESLogger logger)
                                                   throws IOException
```
    Reads a MetadataSnapshot from the given index locations or returns an empty snapshot if it can't be read.
    
    Throws:
    
    IOException - if the index we try to read is corrupted
  - canOpenIndex
```
public static boolean canOpenIndex(ESLogger logger,
                                   File... indexLocations)
                            throws IOException
```
    Returns true iff the given location contains an index an the index can be successfully opened. This includes reading the segment infos and possible corruption markers.
    
    Throws:
    
    IOException
  - createVerifyingOutput
```
public org.apache.lucene.store.IndexOutput createVerifyingOutput(String fileName,
                                                                 StoreFileMetaData metadata,
                                                                 org.apache.lucene.store.IOContext context)
                                                          throws IOException
```
    The returned IndexOutput might validate the files checksum if the file has been written with a newer lucene version and the metadata holds the necessary information to detect that it was been written by Lucene 4.8 or newer. If it has only a legacy checksum, returned IndexOutput will not verify the checksum.
    Note: Checksums are calculated nevertheless since lucene does it by default since version 4.8.0. This method only adds the verification against the checksum in the given metadata and does not add any significant overhead.
    
    Throws:
    
    IOException
  - verify
```
public static void verify(org.apache.lucene.store.IndexOutput output)
                   throws IOException
```
    Throws:
    
    IOException
  - openVerifyingInput
```
public org.apache.lucene.store.IndexInput openVerifyingInput(String filename,
                                                             org.apache.lucene.store.IOContext context,
                                                             StoreFileMetaData metadata)
                                                      throws IOException
```
    Throws:
    
    IOException
  - verify
```
public static void verify(org.apache.lucene.store.IndexInput input)
                   throws IOException
```
    Throws:
    
    IOException
  - checkIntegrity
```
public boolean checkIntegrity(StoreFileMetaData md)
```
  - checkIntegrity
```
public static boolean checkIntegrity(StoreFileMetaData md,
                                     org.apache.lucene.store.Directory directory)
```
  - isMarkedCorrupted
```
public boolean isMarkedCorrupted()
                          throws IOException
```
    Throws:
    
    IOException
  - removeCorruptionMarker
```
public void removeCorruptionMarker()
                            throws IOException
```
    Deletes all corruption markers from this store.
    
    Throws:
    
    IOException
  - failIfCorrupted
```
public void failIfCorrupted()
                     throws IOException
```
    Throws:
    
    IOException
  - cleanup
```
public void cleanup(String reason,
                    Set<String> filesToClean)
             throws IOException
```
    This method deletes every file in this store that is not contained in the given source meta data or is a legacy checksum file.
    
    Parameters:
    
    reason - the reason for this cleanup operation logged for each deleted file
    
    filesToClean - the file names used for cleanup. all files names in this metadata should be kept around.
    
    Throws:
    
    IOException - if an IOException occurs
  - cleanupAndVerify
```
public void cleanupAndVerify(String reason,
                             Store.MetadataSnapshot sourceMetaData)
                      throws IOException
```
    This method deletes every file in this store that is not contained in the given source meta data or is a legacy checksum file. After the delete it pulls the latest metadata snapshot from the store and compares it to the given snapshot. If the snapshots are inconsistent an illegal state exception is thrown
    
    Parameters:
    
    reason - the reason for this cleanup operation logged for each deleted file
    
    sourceMetaData - the metadata used for cleanup. all files in this metadata should be kept around.
    
    Throws:
    
    IOException - if an IOException occurs
    
    ElasticsearchIllegalStateException - if the latest snapshot in this store differs from the given one after the cleanup.
  - refCount
```
public int refCount()
```
    Returns the current reference count.
  - logDeleteFile
```
public void logDeleteFile(String message,
                          String fileName)
```
    Log that we are about to delete this file, to the index.store.deletes component.
  - logDeleteFile
```
public static void logDeleteFile(org.apache.lucene.store.Directory dir,
                                 String message,
                                 String fileName)
```
    Log that we are about to delete this file, to the index.store.deletes component.
  - isChecksum
```
public static final boolean isChecksum(String name)
```
  - digestToString
```
public static String digestToString(long digest)
```
    Produces a string representation of the given digest value.
  - deleteQuiet
```
public void deleteQuiet(String... files)
```
  - markStoreCorrupted
```
public void markStoreCorrupted(IOException exception)
                        throws IOException
```
    Marks this store as corrupted. This method writes a corrupted_${uuid} file containing the given exception message. If a store contains a corrupted_${uuid} file isMarkedCorrupted() will return true.
    
    Throws:
    
    IOException

Class Store

Nested Class Summary

Nested Classes

Field Summary

Fields

Fields inherited from class org.elasticsearch.index.shard.AbstractIndexShardComponent

Constructor Summary

Constructors

Method Summary

Methods inherited from class org.elasticsearch.index.shard.AbstractIndexShardComponent

Methods inherited from class java.lang.Object

Field Detail

INDEX_STORE_STATS_REFRESH_INTERVAL

CHECKSUMS_PREFIX

Constructor Detail

Store

Store

Method Detail

directory

readLastCommittedSegmentsInfo

getMetadataOrEmpty

getMetadata

getMetadata

renameTempFilesSafe

stats

renameFile

incRef

tryIncRef

decRef

close

readMetadataSnapshot

canOpenIndex

createVerifyingOutput

verify

openVerifyingInput

verify

checkIntegrity

checkIntegrity

isMarkedCorrupted

removeCorruptionMarker

failIfCorrupted

cleanup

cleanupAndVerify

refCount

logDeleteFile

logDeleteFile

isChecksum

digestToString

deleteQuiet

markStoreCorrupted