AbstractHFileWriter (Apache HBase 1.2.12 API)

java.lang.Object
- org.apache.hadoop.hbase.io.hfile.AbstractHFileWriter

All Implemented Interfaces:

Closeable, AutoCloseable, HFile.Writer

Direct Known Subclasses:

HFileWriterV2
```
@InterfaceAudience.Private
public abstract class AbstractHFileWriter
extends Object
implements HFile.Writer
```
Common functionality needed by all versions of HFile writers.

Field Summary

Fields
Modifier and Type	Field and Description
`protected HFileDataBlockEncoder`	`blockEncoder` The data block encoding which will be used.
`protected CacheConfig`	`cacheConf` Cache configuration for caching data on write.
`protected boolean`	`closeOutputStream` True if we opened the `outputStream` (and so will close it).
`protected KeyValue.KVComparator`	`comparator` Key comparator.
`protected long`	`entryCount` Total # of key/value entries, i.e.
`protected HFile.FileInfo`	`fileInfo` A "file info" block: a key-value map of file-wide metadata.
`protected Cell`	`firstCellInBlock` First cell in a block.
`protected HFileContext`	`hFileContext`
`protected Cell`	`lastCell` The Cell previously appended.
`protected List<org.apache.hadoop.io.Writable>`	`metaData` `Writable`s representing meta block data.
`protected List<byte[]>`	`metaNames` Meta block names.
`protected String`	`name` Name for this object used when logging or in toString.
`protected org.apache.hadoop.fs.FSDataOutputStream`	`outputStream` FileSystem stream to write into.
`protected org.apache.hadoop.fs.Path`	`path` May be null if we were passed a stream.
`protected long`	`totalKeyLength` Used for calculating the average key length.
`protected long`	`totalUncompressedBytes` Total uncompressed bytes, maybe calculate a compression ratio later.
`protected long`	`totalValueLength` Used for calculating the average value length.

Constructor Summary

Constructors
Constructor and Description
`AbstractHFileWriter(CacheConfig cacheConf, org.apache.hadoop.fs.FSDataOutputStream outputStream, org.apache.hadoop.fs.Path path, KeyValue.KVComparator comparator, HFileContext fileContext)`

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`appendFileInfo(byte[] k, byte[] v)` Add to the file info.
`protected boolean`	`checkKey(Cell cell)` Checks that the given Cell's key does not violate the key order.
`protected void`	`checkValue(byte[] value, int offset, int length)` Checks the given value for validity.
`static Compression.Algorithm`	`compressionByName(String algoName)`
`protected static org.apache.hadoop.fs.FSDataOutputStream`	`createOutputStream(org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path path, InetSocketAddress[] favoredNodes)` A helper method to create HFile output streams in constructors
`protected void`	`finishClose(FixedFileTrailer trailer)` Sets remaining trailer fields, writes the trailer to disk, and optionally closes the output stream.
`protected void`	`finishFileInfo()` Add last bits of metadata to file info before it is written out.
`org.apache.hadoop.fs.Path`	`getPath()`
`String`	`toString()`
`protected void`	`writeFileInfo(FixedFileTrailer trailer, DataOutputStream out)` Sets the file info offset in the trailer, finishes up populating fields in the file info, and writes the file info into the given data output.

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

Methods inherited from interface org.apache.hadoop.hbase.io.hfile.HFile.Writer
addDeleteFamilyBloomFilter, addGeneralBloomFilter, addInlineBlockWriter, append, appendMetaBlock, getFileContext

Methods inherited from interface java.io.Closeable
close

- Field Detail
  - lastCell
```
protected Cell lastCell
```
    The Cell previously appended. Becomes the last cell in the file.
  - outputStream
```
protected org.apache.hadoop.fs.FSDataOutputStream outputStream
```
    FileSystem stream to write into.
  - closeOutputStream
```
protected final boolean closeOutputStream
```
    True if we opened the outputStream (and so will close it).
  - fileInfo
```
protected HFile.FileInfo fileInfo
```
    A "file info" block: a key-value map of file-wide metadata.
  - entryCount
```
protected long entryCount
```
    Total # of key/value entries, i.e. how many times add() was called.
  - totalKeyLength
```
protected long totalKeyLength
```
    Used for calculating the average key length.
  - totalValueLength
```
protected long totalValueLength
```
    Used for calculating the average value length.
  - totalUncompressedBytes
```
protected long totalUncompressedBytes
```
    Total uncompressed bytes, maybe calculate a compression ratio later.
  - comparator
```
protected final KeyValue.KVComparator comparator
```
    Key comparator. Used to ensure we write in order.
  - metaNames
```
protected List<byte[]> metaNames
```
    Meta block names.
  - metaData
```
protected List<org.apache.hadoop.io.Writable> metaData
```
    Writables representing meta block data.
  - firstCellInBlock
```
protected Cell firstCellInBlock
```
    First cell in a block. This reference should be short-lived since we write hfiles in a burst.
  - path
```
protected final org.apache.hadoop.fs.Path path
```
    May be null if we were passed a stream.
  - cacheConf
```
protected final CacheConfig cacheConf
```
    Cache configuration for caching data on write.
  - name
```
protected final String name
```
    Name for this object used when logging or in toString. Is either the result of a toString on stream or else name of passed file Path.
  - blockEncoder
```
protected final HFileDataBlockEncoder blockEncoder
```
    The data block encoding which will be used. NoOpDataBlockEncoder.INSTANCE if there is no encoding.
  - hFileContext
```
protected final HFileContext hFileContext
```
- Constructor Detail
  - AbstractHFileWriter
```
public AbstractHFileWriter(CacheConfig cacheConf,
                   org.apache.hadoop.fs.FSDataOutputStream outputStream,
                   org.apache.hadoop.fs.Path path,
                   KeyValue.KVComparator comparator,
                   HFileContext fileContext)
```
- Method Detail
  - finishFileInfo
```
protected void finishFileInfo()
                       throws IOException
```
    Add last bits of metadata to file info before it is written out.
    
    Throws:
    
    IOException
  - appendFileInfo
```
public void appendFileInfo(byte[] k,
                  byte[] v)
                    throws IOException
```
    Add to the file info. All added key/value pairs can be obtained using HFile.Reader.loadFileInfo().
    
    Specified by:
    
    appendFileInfo in interface HFile.Writer
    
    Parameters:
    k - Key
    v - Value
    
    Throws:
    
    IOException - in case the key or the value are invalid
  - writeFileInfo
```
protected final void writeFileInfo(FixedFileTrailer trailer,
                 DataOutputStream out)
                            throws IOException
```
    Sets the file info offset in the trailer, finishes up populating fields in the file info, and writes the file info into the given data output. The reason the data output is not always outputStream is that we store file info as a block in version 2.
    
    Parameters:
    trailer - fixed file trailer
    out - the data output to write the file info to
    
    Throws:
    
    IOException
  - checkKey
```
protected boolean checkKey(Cell cell)
                    throws IOException
```
    Checks that the given Cell's key does not violate the key order.
    
    Parameters:
    cell - Cell whose key to check.
    
    Returns:
    true if the key is duplicate
    
    Throws:
    
    IOException - if the key or the key order is wrong
  - checkValue
```
protected void checkValue(byte[] value,
              int offset,
              int length)
                   throws IOException
```
    Checks the given value for validity.
    
    Throws:
    
    IOException
  - getPath
```
public org.apache.hadoop.fs.Path getPath()
```
    Specified by:
    
    getPath in interface HFile.Writer
    
    Returns:
    Path or null if we were passed a stream rather than a Path.
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - finishClose
```
protected void finishClose(FixedFileTrailer trailer)
                    throws IOException
```
    Sets remaining trailer fields, writes the trailer to disk, and optionally closes the output stream.
    
    Throws:
    
    IOException
  - compressionByName
```
public static Compression.Algorithm compressionByName(String algoName)
```
  - createOutputStream
```
protected static org.apache.hadoop.fs.FSDataOutputStream createOutputStream(org.apache.hadoop.conf.Configuration conf,
                                                         org.apache.hadoop.fs.FileSystem fs,
                                                         org.apache.hadoop.fs.Path path,
                                                         InetSocketAddress[] favoredNodes)
                                                                     throws IOException
```
    A helper method to create HFile output streams in constructors
    
    Throws:
    
    IOException

Class AbstractHFileWriter

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.hadoop.hbase.io.hfile.HFile.Writer

Methods inherited from interface java.io.Closeable

Field Detail

lastCell

outputStream

closeOutputStream

fileInfo

entryCount

totalKeyLength

totalValueLength

totalUncompressedBytes

comparator

metaNames

metaData

firstCellInBlock

path

cacheConf

name

blockEncoder

hFileContext

Constructor Detail

AbstractHFileWriter

Method Detail

finishFileInfo

appendFileInfo

writeFileInfo

checkKey

checkValue

getPath

toString

finishClose

compressionByName

createOutputStream