org.apache.hadoop.hbase.io

Class Reference

java.lang.Object

org.apache.hadoop.hbase.io.Reference

@InterfaceAudience.Private
public class Reference
extends Object

A reference to the top or bottom half of a store file where 'bottom' is the first half of the file containing the keys that sort lowest and 'top' is the second half of the file with keys that sort greater than those of the bottom half. The file referenced lives under a different region. References are made at region split time.

References work with a special half store file type. References know how to write out the reference format in the file system and are what is juggled when references are mixed in with direct store files. The half store file type is used reading the referred to file.

References to store files located over in some other region look like this in the file system 1278437856009925445.3323223323: i.e. an id followed by hash of the referenced region. Note, a region is itself not splittable if it has instances of store file references. References are cleaned up by compactions.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	Reference.Range For split HStoreFiles, it specifies if the file covers the lower half or the upper half of the key range

Field Summary

Fields

Modifier and Type	Field and Description
private Reference.Range	region
private byte[]	splitkey

Constructor Summary

Constructors

Constructor and Description
Reference() Deprecated. need by pb serialization
Reference(byte[] splitRow, Reference.Range fr) Constructor

Method Summary

Modifier and Type	Method and Description
org.apache.hadoop.hbase.shaded.protobuf.generated.FSProtos.Reference	convert()
static Reference	convert(org.apache.hadoop.hbase.shaded.protobuf.generated.FSProtos.Reference r)
static Reference	createBottomReference(byte[] splitRow)
static Reference	createTopReference(byte[] splitRow)
boolean	equals(Object o)
Reference.Range	getFileRegion()
byte[]	getSplitKey()
int	hashCode()
static boolean	isTopFileRegion(Reference.Range r)
static Reference	read(org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path p) Read a Reference from FileSystem.
void	readFields(DataInput in) Deprecated. Writables are going away. Use the pb serialization methods instead. Remove in a release after 0.96 goes out. This is here only to migrate old Reference files written with Writables before 0.96.
(package private) byte[]	toByteArray() Use this when writing to a stream and you want to use the pb mergeDelimitedFrom (w/o the delimiter, pb reads to EOF which may not be what you want).
String	toString()
org.apache.hadoop.fs.Path	write(org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.Path p)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

splitkey

private byte[] splitkey

region

private Reference.Range region

Constructor Detail

Reference

Reference(byte[] splitRow,
          Reference.Range fr)

Constructor

Parameters:

splitRow - This is row we are splitting around.

fr -

Reference

@Deprecated
public Reference()

Deprecated. need by pb serialization

Used by serializations.

Method Detail

createTopReference

public static Reference createTopReference(byte[] splitRow)

Parameters:

splitRow -

Returns:

A Reference that points at top half of a an hfile

createBottomReference

public static Reference createBottomReference(byte[] splitRow)

Parameters:

splitRow -

Returns:

A Reference that points at the bottom half of a an hfile

getFileRegion

public Reference.Range getFileRegion()

Returns:

Range

getSplitKey

public byte[] getSplitKey()

Returns:

splitKey

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

isTopFileRegion

public static boolean isTopFileRegion(Reference.Range r)

readFields

@Deprecated
public void readFields(DataInput in)
                            throws IOException

Deprecated. Writables are going away. Use the pb serialization methods instead. Remove in a release after 0.96 goes out. This is here only to migrate old Reference files written with Writables before 0.96.

Throws:

IOException

write

public org.apache.hadoop.fs.Path write(org.apache.hadoop.fs.FileSystem fs,
                                       org.apache.hadoop.fs.Path p)
                                throws IOException

Throws:

IOException

read

public static Reference read(org.apache.hadoop.fs.FileSystem fs,
                             org.apache.hadoop.fs.Path p)
                      throws IOException

Read a Reference from FileSystem.

Parameters:

fs -

p -

Returns:

New Reference made from passed p

Throws:

IOException

convert

public org.apache.hadoop.hbase.shaded.protobuf.generated.FSProtos.Reference convert()

convert

public static Reference convert(org.apache.hadoop.hbase.shaded.protobuf.generated.FSProtos.Reference r)

toByteArray

byte[] toByteArray()
            throws IOException

Use this when writing to a stream and you want to use the pb mergeDelimitedFrom (w/o the delimiter, pb reads to EOF which may not be what you want).

Returns:

This instance serialized as a delimited protobuf w/ a magic pb prefix.

Throws:

IOException

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object