Java SDK Documentation  8.1
com.vertica.sdk.FileManager Class Referenceabstract
Collaboration diagram for com.vertica.sdk.FileManager:
Collaboration graph

Public Member Functions

abstract void closeReader (long readerID) throws UdfException, DestroyInvocation
 
abstract void closeWriter (long writerID) throws UdfException, DestroyInvocation
 
abstract int deleteIt (String fileName, boolean isRecursively) throws UdfException, DestroyInvocation
 
abstract void finalize ()
 
abstract boolean initDFSFile (DFSFile file) throws UdfException, DestroyInvocation
 
abstract List< DFSFilelistFiles (String fileName) throws UdfException, DestroyInvocation
 
abstract long openForRead (String fileName) throws UdfException, DestroyInvocation
 
abstract long openForWrite (String fileName, DFSFile.DFSScope dfsScope, DFSFile.DFSDistribution dfsDistrib) throws UdfException, DestroyInvocation
 
abstract int read (long readerID, ByteBuffer buffer, int size) throws UdfException, DestroyInvocation
 
abstract long seek (long readerID, long offset, int origin) throws UdfException, DestroyInvocation
 
abstract int write (long writerID, ByteBuffer buffer) throws UdfException, DestroyInvocation
 

Detailed Description

File Manager is a session level co-ordinator, which will be used by DFSFile, DFSFileReader and DFSFileWriter to interact with Catalog and Storage system of Vertica.

Member Function Documentation

abstract void com.vertica.sdk.FileManager.closeReader ( long  readerID) throws UdfException, DestroyInvocation
abstract

Closes the file opened for reading, identified by 'readerID'

abstract void com.vertica.sdk.FileManager.closeWriter ( long  writerID) throws UdfException, DestroyInvocation
abstract

Closes teh file opened for writing, identified by 'writerID'

abstract int com.vertica.sdk.FileManager.deleteIt ( String  fileName,
boolean  isRecursively 
) throws UdfException, DestroyInvocation
abstract

Deletes a DFSFile, identified by full path 'fileName'.

Returns
0 if successful, throw exceptions if there are errors
abstract void com.vertica.sdk.FileManager.finalize ( )
abstract

Finalizes a plan/query/statement. Should only invoke on the initiator node of a query. Complete file replication and commit metadata into the catalog. returns nothing, throws exceptions if there are errors.

abstract boolean com.vertica.sdk.FileManager.initDFSFile ( DFSFile  file) throws UdfException, DestroyInvocation
abstract

Initialize a DFSFile upon constructing. returns true if file exists in the DFS, false otherwise, throws exceptions if there are errors.

abstract List<DFSFile> com.vertica.sdk.FileManager.listFiles ( String  fileName) throws UdfException, DestroyInvocation
abstract

Lists file under the path specified by 'fileName'

Returns
a list of DFSFile found under the path.
abstract long com.vertica.sdk.FileManager.openForRead ( String  fileName) throws UdfException, DestroyInvocation
abstract

Opens a file for reading

Returns
A unique identifier for the file opened. Return value is less than 0 if there are errors
abstract long com.vertica.sdk.FileManager.openForWrite ( String  fileName,
DFSFile.DFSScope  dfsScope,
DFSFile.DFSDistribution  dfsDistrib 
) throws UdfException, DestroyInvocation
abstract

Opens a file for writing

Returns
A unique identifier for the file opened. Return value is less tan 0 if there are errors
abstract int com.vertica.sdk.FileManager.read ( long  readerID,
ByteBuffer  buffer,
int  size 
) throws UdfException, DestroyInvocation
abstract

Reads 'size' of bytes into buffer from the file identified by 'readerID'.

Returns
number of bytes read, 0 if no bytes were read, indicates the EOF. throws exceptions if there are errors
abstract long com.vertica.sdk.FileManager.seek ( long  readerID,
long  offset,
int  origin 
) throws UdfException, DestroyInvocation
abstract

Reposition the read file offset

Returns
the new file offset.
abstract int com.vertica.sdk.FileManager.write ( long  writerID,
ByteBuffer  buffer 
) throws UdfException, DestroyInvocation
abstract

Writes bytes into the file identified by 'writerID' from the buffer. Bytes are retrieved from buffer starting from the current position till it's limit. Current position will be advanced depending on how many bytes are written.

Returns
number of bytes written, less than 0 if there are any errors.