com.gpudb.filesystem.download

Class FileDownloader

java.lang.Object

com.gpudb.filesystem.common.FileOperation

com.gpudb.filesystem.download.FileDownloader

public class FileDownloader
extends FileOperation

This is an internal class and not meant to be used by the end users of the filesystem API. The consequences of using this class directly in client code is not guaranteed and maybe undesirable. This class handles downloading of either single part file or multiple part downloads. This class extends the class FileOperation and provides additional functionalities of creating instances of DownloadIoJob, starting them and waiting for them to terminate. The main exposed method to call is download() ()} which calls two private methods named downloadFullFiles() ()} and downloadMultiPartFiles() ()} respectively. The method downloadFullFiles() ()} does the download by calling the Java endpoint to download all files in one go. The method downloadMultiPartFiles() ()} does the downloads by creating background threads since each file could take a long time to download. The multiple parts of a single file are downloaded sequentially in a single thread and multiple files are downloaded in different threads.

Field Summary

Fields inherited from class com.gpudb.filesystem.common.FileOperation

db, dirName, fileHandlerOptions, fileNames, fullFileBatchManager, fullFileList, fullRemoteFileNames, KIFS_PATH_SEPARATOR, multiPartList, multiPartRemoteFileNames, namesOfFilesUploaded, opMode, recursive

Constructor Summary

Constructors

Constructor and Description
FileDownloader(GPUdb db, List<String> fileNames, String localDirName, DownloadOptions downloadOptions, FileDownloadListener callback, GPUdbFileHandler.Options fileHandlerOptions) Constructor

Method Summary

Modifier and Type	Method and Description
void	download() This is the main download method which is to be called by the users of this class.
String	getEncoding()
void	setEncoding(String encoding)

Methods inherited from class com.gpudb.filesystem.common.FileOperation

decideMultiPart, getFileInfoFromServer, getFileInfoFromServer, getKifsPathSeparator, getNamesOfFilesUploaded, localDirExists, localFileExists, parseFileNames, sortFilesIntoFullAndMultipartLists, traverseLocalDirectories

Methods inherited from class java.lang.Object

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

Constructor Detail

FileDownloader

public FileDownloader(GPUdb db,
                      List<String> fileNames,
                      String localDirName,
                      DownloadOptions downloadOptions,
                      FileDownloadListener callback,
                      GPUdbFileHandler.Options fileHandlerOptions)
               throws GPUdbException

Constructor

Parameters:

db - - GPUdb - The GPUdb instance

fileNames - - List - The names of the files on the KIFS to be downloaded.

localDirName - - String - The name of the directory on the KIFS.

downloadOptions - - DownloadOptions - Various options

callback - - FileDownloadListener - The callback object used

fileHandlerOptions - - a GPUdbFileHandler.Options type object

Throws:

GPUdbException

Method Detail

getEncoding

public String getEncoding()

setEncoding

public void setEncoding(String encoding)

download

public void download()
              throws GPUdbException

This is the main download method which is to be called by the users of this class. Internally depending whether there are files to be downloaded one shot or in parts it will call the methods downloadFullFiles() ()} and downloadMultiPartFiles() ()}

Throws:

GPUdbException