org.apache.hadoop.hbase.io.hfile.bucket

类 FileIOEngine

java.lang.Object

org.apache.hadoop.hbase.io.hfile.bucket.FileIOEngine

所有已实现的接口:

IOEngine

@InterfaceAudience.Private
public class FileIOEngine
extends Object
implements IOEngine

IO engine that stores data to a file on the local file system.

字段概要

字段

限定符和类型	字段和说明
static String	FILE_DELIMITER

构造器概要

构造器

构造器和说明
FileIOEngine(long capacity, boolean maintainPersistence, String... filePaths)

方法概要

限定符和类型	方法和说明
boolean	isPersistent() File IO engine is always able to support persistent storage for the cache
Cacheable	read(long offset, int length, CacheableDeserializer<Cacheable> deserializer) Transfers data from file to the given byte buffer
void	shutdown() Close the file
void	sync() Sync the data to file after writing
String	toString()
void	write(ByteBuffer srcBuffer, long offset) Transfers data from the given byte buffer to file
void	write(ByteBuff srcBuffer, long offset) Transfers the data from the given MultiByteBuffer to IOEngine

从类继承的方法 java.lang.Object

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

从接口继承的方法 org.apache.hadoop.hbase.io.hfile.bucket.IOEngine

usesSharedMemory

字段详细资料

FILE_DELIMITER

public static final String FILE_DELIMITER

另请参阅:

常量字段值

构造器详细资料

FileIOEngine

public FileIOEngine(long capacity,
                    boolean maintainPersistence,
                    String... filePaths)
             throws IOException

抛出:

IOException

方法详细资料

toString

public String toString()

覆盖:

toString 在类中 Object

isPersistent

public boolean isPersistent()

File IO engine is always able to support persistent storage for the cache

指定者:

isPersistent 在接口中 IOEngine

返回:

true

read

public Cacheable read(long offset,
                      int length,
                      CacheableDeserializer<Cacheable> deserializer)
               throws IOException

Transfers data from file to the given byte buffer

指定者:

read 在接口中 IOEngine

参数:

offset - The offset in the file where the first byte to be read

length - The length of buffer that should be allocated for reading from the file channel

deserializer - The deserializer to be used to make a Cacheable from the data.

返回:

number of bytes read

抛出:

IOException

write

public void write(ByteBuffer srcBuffer,
                  long offset)
           throws IOException

Transfers data from the given byte buffer to file

指定者:

write 在接口中 IOEngine

参数:

srcBuffer - the given byte buffer from which bytes are to be read

offset - The offset in the file where the first byte to be written

抛出:

IOException

sync

public void sync()
          throws IOException

Sync the data to file after writing

指定者:

sync 在接口中 IOEngine

抛出:

IOException

shutdown

public void shutdown()

Close the file

指定者:

shutdown 在接口中 IOEngine

write

public void write(ByteBuff srcBuffer,
                  long offset)
           throws IOException

从接口复制的说明: IOEngine

Transfers the data from the given MultiByteBuffer to IOEngine

指定者:

write 在接口中 IOEngine

参数:

srcBuffer - the given MultiBytebufffers from which bytes are to be read

offset - the offset in the IO engine where the first byte to be written

抛出:

IOException