HFileLink (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.io.FileLink
- - org.apache.hadoop.hbase.io.HFileLink

```
@InterfaceAudience.Private
public class HFileLink
extends FileLink
```
HFileLink describes a link to an hfile. An hfile can be served from a region or from the hfile archive directory (/hbase/.archive) HFileLink allows to access the referenced hfile regardless of the location where it is.
Searches for hfiles in the following order and locations:
- /hbase/table/region/cf/hfile
- /hbase/.archive/table/region/cf/hfile
The link checks first in the original path if it is not present it fallbacks to the archived path.

Field Summary

Fields
Modifier and Type	Field and Description
`private org.apache.hadoop.fs.Path`	`archivePath`
`(package private) static Pattern`	`LINK_NAME_PATTERN` Define the HFile Link name parser in the form of: table=region-hfile
`static String`	`LINK_NAME_REGEX` A non-capture group, for HFileLink, so that this can be embedded.
`private static org.apache.commons.logging.Log`	`LOG`
`private org.apache.hadoop.fs.Path`	`originPath`
`private static Pattern`	`REF_OR_HFILE_LINK_PATTERN` The pattern should be used for hfile and reference links that can be found in /hbase/table/region/family/
`private org.apache.hadoop.fs.Path`	`tempPath`

Fields inherited from class org.apache.hadoop.hbase.io.FileLink
BACK_REFERENCES_DIRECTORY_PREFIX

Constructor Summary

Constructors
Constructor and Description
`HFileLink(org.apache.hadoop.fs.Path originPath, org.apache.hadoop.fs.Path tempPath, org.apache.hadoop.fs.Path archivePath)` Dead simple hfile link constructor

Method Summary

Methods
Modifier and Type	Method and Description
`static HFileLink`	`build(org.apache.hadoop.conf.Configuration conf, TableName table, String region, String family, String hfile)` Create an HFileLink instance from table/region/family/hfile location
`static HFileLink`	`buildFromHFileLinkPattern(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.Path hFileLinkPattern)`
`static HFileLink`	`buildFromHFileLinkPattern(org.apache.hadoop.fs.Path rootDir, org.apache.hadoop.fs.Path archiveDir, org.apache.hadoop.fs.Path hFileLinkPattern)`
`static boolean`	`create(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path dstFamilyPath, HRegionInfo hfileRegionInfo, String hfileName)` Create a new HFileLink
`static boolean`	`create(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path dstFamilyPath, HRegionInfo hfileRegionInfo, String hfileName, boolean createBackRef)` Create a new HFileLink
`static boolean`	`create(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path dstFamilyPath, TableName linkedTable, String linkedRegion, String hfileName)` Create a new HFileLink
`static boolean`	`create(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path dstFamilyPath, TableName linkedTable, String linkedRegion, String hfileName, boolean createBackRef)` Create a new HFileLink
`(package private) static String`	`createBackReferenceName(String tableNameStr, String regionName)` Create the back reference name
`static boolean`	`createFromHFileLink(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path dstFamilyPath, String hfileLinkName)` Create a new HFileLink starting from a hfileLink name
`static boolean`	`createFromHFileLink(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path dstFamilyPath, String hfileLinkName, boolean createBackRef)` Create a new HFileLink starting from a hfileLink name
`static String`	`createHFileLinkName(HRegionInfo hfileRegionInfo, String hfileName)` Create a new HFileLink name
`static String`	`createHFileLinkName(TableName tableName, String regionName, String hfileName)` Create a new HFileLink name
`static org.apache.hadoop.fs.Path`	`createPath(TableName table, String region, String family, String hfile)` Create an HFileLink relative path for the table/region/family/hfile location
`org.apache.hadoop.fs.Path`	`getArchivePath()`
`static org.apache.hadoop.fs.Path`	`getHFileFromBackReference(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.Path linkRefPath)` Get the full path of the HFile referenced by the back reference
`static org.apache.hadoop.fs.Path`	`getHFileFromBackReference(org.apache.hadoop.fs.Path rootDir, org.apache.hadoop.fs.Path linkRefPath)` Get the full path of the HFile referenced by the back reference
`private static org.apache.hadoop.fs.Path`	`getHFileLinkPatternRelativePath(org.apache.hadoop.fs.Path path)` Convert a HFileLink path to a table relative path.
`org.apache.hadoop.fs.Path`	`getOriginPath()`
`static String`	`getReferencedHFileName(String fileName)` Get the HFile name of the referenced link
`static String`	`getReferencedRegionName(String fileName)` Get the Region name of the referenced link
`static TableName`	`getReferencedTableName(String fileName)` Get the Table name of the referenced link
`static boolean`	`isHFileLink(org.apache.hadoop.fs.Path path)`
`static boolean`	`isHFileLink(String fileName)`
`(package private) static Pair<TableName,String>`	`parseBackReferenceName(String name)`

Methods inherited from class org.apache.hadoop.hbase.io.FileLink
equals, exists, getAvailablePath, getBackReferenceFileName, getBackReferencesDir, getFileStatus, getLocations, hashCode, isBackReferencesDir, open, open, setLocations, toString

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

- Field Detail
  - LOG
```
private static final org.apache.commons.logging.Log LOG
```
  - LINK_NAME_REGEX
```
public static final String LINK_NAME_REGEX
```
    A non-capture group, for HFileLink, so that this can be embedded. The HFileLink describe a link to an hfile in a different table/region and the name is in the form: table=region-hfile.
    Table name is ([a-zA-Z_0-9][a-zA-Z_0-9.-]*), so '=' is an invalid character for the table name. Region name is ([a-f0-9]+), so '-' is an invalid character for the region name. HFile is ([0-9a-f]+(?:_SeqId_[0-9]+_)?) covering the plain hfiles (uuid) and the bulk loaded (_SeqId_[0-9]+_) hfiles.
  - LINK_NAME_PATTERN
```
static final Pattern LINK_NAME_PATTERN
```
    Define the HFile Link name parser in the form of: table=region-hfile
  - REF_OR_HFILE_LINK_PATTERN
```
private static final Pattern REF_OR_HFILE_LINK_PATTERN
```
    The pattern should be used for hfile and reference links that can be found in /hbase/table/region/family/
  - archivePath
```
private final org.apache.hadoop.fs.Path archivePath
```
  - originPath
```
private final org.apache.hadoop.fs.Path originPath
```
  - tempPath
```
private final org.apache.hadoop.fs.Path tempPath
```
- Constructor Detail
  - HFileLink
```
public HFileLink(org.apache.hadoop.fs.Path originPath,
         org.apache.hadoop.fs.Path tempPath,
         org.apache.hadoop.fs.Path archivePath)
```
    Dead simple hfile link constructor
- Method Detail
  - buildFromHFileLinkPattern
```
public static final HFileLink buildFromHFileLinkPattern(org.apache.hadoop.conf.Configuration conf,
                                  org.apache.hadoop.fs.Path hFileLinkPattern)
                                                 throws IOException
```
    Parameters:
    conf - Configuration from which to extract specific archive locations
    hFileLinkPattern - The path ending with a HFileLink pattern. (table=region-hfile)
    
    Throws:
    
    IOException - on unexpected error.
  - buildFromHFileLinkPattern
```
public static final HFileLink buildFromHFileLinkPattern(org.apache.hadoop.fs.Path rootDir,
                                  org.apache.hadoop.fs.Path archiveDir,
                                  org.apache.hadoop.fs.Path hFileLinkPattern)
```
    Parameters:
    rootDir - Path to the root directory where hbase files are stored
    archiveDir - Path to the hbase archive directory
    hFileLinkPattern - The path of the HFile Link.
  - createPath
```
public static org.apache.hadoop.fs.Path createPath(TableName table,
                                   String region,
                                   String family,
                                   String hfile)
```
    Create an HFileLink relative path for the table/region/family/hfile location
    
    Parameters:
    table - Table name
    region - Region Name
    family - Family Name
    hfile - HFile Name
    
    Returns:
    the relative Path to open the specified table/region/family/hfile link
  - build
```
public static HFileLink build(org.apache.hadoop.conf.Configuration conf,
              TableName table,
              String region,
              String family,
              String hfile)
                       throws IOException
```
    Create an HFileLink instance from table/region/family/hfile location
    
    Parameters:
    conf - Configuration from which to extract specific archive locations
    table - Table name
    region - Region Name
    family - Family Name
    hfile - HFile Name
    
    Returns:
    Link to the file with the specified table/region/family/hfile location
    
    Throws:
    
    IOException - on unexpected error.
  - getOriginPath
```
public org.apache.hadoop.fs.Path getOriginPath()
```
    Returns:
    the origin path of the hfile.
  - getArchivePath
```
public org.apache.hadoop.fs.Path getArchivePath()
```
    Returns:
    the path of the archived hfile.
  - isHFileLink
```
public static boolean isHFileLink(org.apache.hadoop.fs.Path path)
```
    Parameters:
    path - Path to check.
    
    Returns:
    True if the path is a HFileLink.
  - isHFileLink
```
public static boolean isHFileLink(String fileName)
```
    Parameters:
    fileName - File name to check.
    
    Returns:
    True if the path is a HFileLink.
  - getHFileLinkPatternRelativePath
```
private static org.apache.hadoop.fs.Path getHFileLinkPatternRelativePath(org.apache.hadoop.fs.Path path)
```
    Convert a HFileLink path to a table relative path. e.g. the link: /hbase/test/0123/cf/testtb=4567-abcd becomes: /hbase/testtb/4567/cf/abcd
    
    Parameters:
    path - HFileLink path
    
    Returns:
    Relative table path
    
    Throws:
    
    IOException - on unexpected error.
  - getReferencedHFileName
```
public static String getReferencedHFileName(String fileName)
```
    Get the HFile name of the referenced link
    
    Parameters:
    fileName - HFileLink file name
    
    Returns:
    the name of the referenced HFile
  - getReferencedRegionName
```
public static String getReferencedRegionName(String fileName)
```
    Get the Region name of the referenced link
    
    Parameters:
    fileName - HFileLink file name
    
    Returns:
    the name of the referenced Region
  - getReferencedTableName
```
public static TableName getReferencedTableName(String fileName)
```
    Get the Table name of the referenced link
    
    Parameters:
    fileName - HFileLink file name
    
    Returns:
    the name of the referenced Table
  - createHFileLinkName
```
public static String createHFileLinkName(HRegionInfo hfileRegionInfo,
                         String hfileName)
```
    Create a new HFileLink name
    
    Parameters:
    hfileRegionInfo - - Linked HFile Region Info
    hfileName - - Linked HFile name
    
    Returns:
    file name of the HFile Link
  - createHFileLinkName
```
public static String createHFileLinkName(TableName tableName,
                         String regionName,
                         String hfileName)
```
    Create a new HFileLink name
    
    Parameters:
    tableName - - Linked HFile table name
    regionName - - Linked HFile region name
    hfileName - - Linked HFile name
    
    Returns:
    file name of the HFile Link
  - create
```
public static boolean create(org.apache.hadoop.conf.Configuration conf,
             org.apache.hadoop.fs.FileSystem fs,
             org.apache.hadoop.fs.Path dstFamilyPath,
             HRegionInfo hfileRegionInfo,
             String hfileName)
                      throws IOException
```
    Create a new HFileLink
    It also adds a back-reference to the hfile back-reference directory to simplify the reference-count and the cleaning process.
    
    Parameters:
    conf - Configuration to read for the archive directory name
    fs - FileSystem on which to write the HFileLink
    dstFamilyPath - - Destination path (table/region/cf/)
    hfileRegionInfo - - Linked HFile Region Info
    hfileName - - Linked HFile name
    
    Returns:
    true if the file is created, otherwise the file exists.
    
    Throws:
    
    IOException - on file or parent directory creation failure
  - create
```
public static boolean create(org.apache.hadoop.conf.Configuration conf,
             org.apache.hadoop.fs.FileSystem fs,
             org.apache.hadoop.fs.Path dstFamilyPath,
             HRegionInfo hfileRegionInfo,
             String hfileName,
             boolean createBackRef)
                      throws IOException
```
    Create a new HFileLink
    It also adds a back-reference to the hfile back-reference directory to simplify the reference-count and the cleaning process.
    
    Parameters:
    conf - Configuration to read for the archive directory name
    fs - FileSystem on which to write the HFileLink
    dstFamilyPath - - Destination path (table/region/cf/)
    hfileRegionInfo - - Linked HFile Region Info
    hfileName - - Linked HFile name
    createBackRef - - Whether back reference should be created. Defaults to true.
    
    Returns:
    true if the file is created, otherwise the file exists.
    
    Throws:
    
    IOException - on file or parent directory creation failure
  - create
```
public static boolean create(org.apache.hadoop.conf.Configuration conf,
             org.apache.hadoop.fs.FileSystem fs,
             org.apache.hadoop.fs.Path dstFamilyPath,
             TableName linkedTable,
             String linkedRegion,
             String hfileName)
                      throws IOException
```
    Create a new HFileLink
    It also adds a back-reference to the hfile back-reference directory to simplify the reference-count and the cleaning process.
    
    Parameters:
    conf - Configuration to read for the archive directory name
    fs - FileSystem on which to write the HFileLink
    dstFamilyPath - - Destination path (table/region/cf/)
    linkedTable - - Linked Table Name
    linkedRegion - - Linked Region Name
    hfileName - - Linked HFile name
    
    Returns:
    true if the file is created, otherwise the file exists.
    
    Throws:
    
    IOException - on file or parent directory creation failure
  - create
```
public static boolean create(org.apache.hadoop.conf.Configuration conf,
             org.apache.hadoop.fs.FileSystem fs,
             org.apache.hadoop.fs.Path dstFamilyPath,
             TableName linkedTable,
             String linkedRegion,
             String hfileName,
             boolean createBackRef)
                      throws IOException
```
    Create a new HFileLink
    It also adds a back-reference to the hfile back-reference directory to simplify the reference-count and the cleaning process.
    
    Parameters:
    conf - Configuration to read for the archive directory name
    fs - FileSystem on which to write the HFileLink
    dstFamilyPath - - Destination path (table/region/cf/)
    linkedTable - - Linked Table Name
    linkedRegion - - Linked Region Name
    hfileName - - Linked HFile name
    createBackRef - - Whether back reference should be created. Defaults to true.
    
    Returns:
    true if the file is created, otherwise the file exists.
    
    Throws:
    
    IOException - on file or parent directory creation failure
  - createFromHFileLink
```
public static boolean createFromHFileLink(org.apache.hadoop.conf.Configuration conf,
                          org.apache.hadoop.fs.FileSystem fs,
                          org.apache.hadoop.fs.Path dstFamilyPath,
                          String hfileLinkName)
                                   throws IOException
```
    Create a new HFileLink starting from a hfileLink name
    It also adds a back-reference to the hfile back-reference directory to simplify the reference-count and the cleaning process.
    
    Parameters:
    conf - Configuration to read for the archive directory name
    fs - FileSystem on which to write the HFileLink
    dstFamilyPath - - Destination path (table/region/cf/)
    hfileLinkName - - HFileLink name (it contains hfile-region-table)
    
    Returns:
    true if the file is created, otherwise the file exists.
    
    Throws:
    
    IOException - on file or parent directory creation failure
  - createFromHFileLink
```
public static boolean createFromHFileLink(org.apache.hadoop.conf.Configuration conf,
                          org.apache.hadoop.fs.FileSystem fs,
                          org.apache.hadoop.fs.Path dstFamilyPath,
                          String hfileLinkName,
                          boolean createBackRef)
                                   throws IOException
```
    Create a new HFileLink starting from a hfileLink name
    It also adds a back-reference to the hfile back-reference directory to simplify the reference-count and the cleaning process.
    
    Parameters:
    conf - Configuration to read for the archive directory name
    fs - FileSystem on which to write the HFileLink
    dstFamilyPath - - Destination path (table/region/cf/)
    hfileLinkName - - HFileLink name (it contains hfile-region-table)
    createBackRef - - Whether back reference should be created. Defaults to true.
    
    Returns:
    true if the file is created, otherwise the file exists.
    
    Throws:
    
    IOException - on file or parent directory creation failure
  - createBackReferenceName
```
static String createBackReferenceName(String tableNameStr,
                             String regionName)
```
    Create the back reference name
  - getHFileFromBackReference
```
public static org.apache.hadoop.fs.Path getHFileFromBackReference(org.apache.hadoop.fs.Path rootDir,
                                                  org.apache.hadoop.fs.Path linkRefPath)
```
    Get the full path of the HFile referenced by the back reference
    
    Parameters:
    rootDir - root hbase directory
    linkRefPath - Link Back Reference path
    
    Returns:
    full path of the referenced hfile
  - parseBackReferenceName
```
static Pair<TableName,String> parseBackReferenceName(String name)
```
  - getHFileFromBackReference
```
public static org.apache.hadoop.fs.Path getHFileFromBackReference(org.apache.hadoop.conf.Configuration conf,
                                                  org.apache.hadoop.fs.Path linkRefPath)
                                                           throws IOException
```
    Get the full path of the HFile referenced by the back reference
    
    Parameters:
    conf - Configuration to read for the archive directory name
    linkRefPath - Link Back Reference path
    
    Returns:
    full path of the referenced hfile
    
    Throws:
    
    IOException - on unexpected error.

Class HFileLink

Field Summary

Fields inherited from class org.apache.hadoop.hbase.io.FileLink

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.hbase.io.FileLink

Methods inherited from class java.lang.Object

Field Detail

LOG

LINK_NAME_REGEX

LINK_NAME_PATTERN

REF_OR_HFILE_LINK_PATTERN

archivePath

originPath

tempPath

Constructor Detail

HFileLink

Method Detail

buildFromHFileLinkPattern

buildFromHFileLinkPattern

createPath

build

getOriginPath

getArchivePath

isHFileLink

isHFileLink

getHFileLinkPatternRelativePath

getReferencedHFileName

getReferencedRegionName

getReferencedTableName

createHFileLinkName

createHFileLinkName

create

create

create

create

createFromHFileLink

createFromHFileLink

createBackReferenceName

getHFileFromBackReference

parseBackReferenceName

getHFileFromBackReference