com.limegroup.gnutella.downloader
Class ResumeDownloader

java.lang.Object
  com.limegroup.gnutella.downloader.ManagedDownloader
      com.limegroup.gnutella.downloader.ResumeDownloader

All Implemented Interfaces:

BandwidthTracker, Downloader, java.io.Serializable

public class ResumeDownloader

extends ManagedDownloader

implements java.io.Serializable

A ManagedDownloader that tries to resume to a specific incomplete file. The ResumeDownloader initially has no locations to download from. Instead it immediately requeries--by hash if possible--and only accepts results that would result in resumes from the specified incomplete file. Do not be confused by the name; ManagedDownloader CAN resume from incomplete files, but it is less strict about its choice of download.

See Also:

Serialized Form

Field Summary

Fields inherited from class com.limegroup.gnutella.downloader.ManagedDownloader

UNKNOWN_FILENAME

Fields inherited from interface com.limegroup.gnutella.Downloader

ABORTED, COMPLETE, CONNECTING, CORRUPT_FILE, COULDNT_MOVE_TO_LIBRARY, DOWNLOADING, GAVE_UP, HASHING, QUEUED, REMOTE_QUEUED, SAVING, WAITING_FOR_CONNECTIONS, WAITING_FOR_RESULTS, WAITING_FOR_RETRY, WAITING_FOR_USER

Constructor Summary

ResumeDownloader(IncompleteFileManager incompleteFileManager, java.io.File incompleteFile, java.lang.String name, int size)
Creates a RequeryDownloader to finish downloading incompleteFile.

Method Summary

protected boolean	allowAddition(RemoteFileDesc other) Overrides ManagedDownloader to allow any RemoteFileDesc that would resume from _incompleteFile.
boolean	conflicts(java.io.File incompleteFile) Overrides ManagedDownloader to reserve _incompleteFile for this download.
int	getContentLength() Overrides ManagedDownloader to display a reasonable file size even when no locations have been found.
java.lang.String	getFileName() Overrides ManagedDownloader to display a reasonable file name even when no locations have been found.
void	initialize(DownloadManager manager, FileManager fileManager, ActivityCallback callback, boolean deserialized) Overrides ManagedDownloader to ensure that progress is initially non-zero and file previewing works.
protected QueryRequest	newRequery(int numRequeries) Overrides ManagedDownloader to use the filename and hash (if present) of the incomplete file.
protected boolean	pauseForRequery(int numRequeries, boolean deserializedFromDisk) This dictates whether this downloader should wait for user input before spawning a Requery.
protected boolean	shouldInitAltLocs(boolean deserializedFromDisk) Subclasses should override this method when necessary.

Methods inherited from class com.limegroup.gnutella.downloader.ManagedDownloader

acceptDownload, addDownload, addDownloadForced, conflicts, discardCorruptDownload, finish, getAddress, getAmountRead, getAverageBandwidth, getBrowseEnabledHost, getBusyHostCount, getChatEnabledHost, getDownloadFragment, getFailedState, getHosts, getMeasuredBandwidth, getNumberOfAlternateLocations, getNumDownloaders, getPossibleHostCount, getQueryCount, getQueuedHostCount, getQueuePosition, getRemainingStateTime, getRetriesWaiting, getState, getVendor, hasBrowseEnabledHost, hasChatEnabledHost, hasRFD, initializeIncompleteFile, measureBandwidth, resume, stop, tryAllDownloads

Methods inherited from class java.lang.Object

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

Constructor Detail

ResumeDownloader

public ResumeDownloader(IncompleteFileManager incompleteFileManager,
                        java.io.File incompleteFile,
                        java.lang.String name,
                        int size)

Creates a RequeryDownloader to finish downloading incompleteFile. This constructor has preconditions on several parameters; putting the burden on the caller makes the method easier to implement, since the superclass constructor immediately starts a download thread.

Parameters:

incompleteFile - the incomplete file to resume to, which MUST be the result of IncompleteFileManager.getFile.

name - the name of the completed file, which MUST be the result of IncompleteFileManager.getCompletedName(incompleteFile)

size - the size of the completed file, which MUST be the result of IncompleteFileManager.getCompletedSize(incompleteFile)

Method Detail

initialize

public void initialize(DownloadManager manager,
                       FileManager fileManager,
                       ActivityCallback callback,
                       boolean deserialized)

Overrides ManagedDownloader to ensure that progress is initially non-zero and file previewing works.

Overrides:

initialize in class ManagedDownloader

Parameters:

deserialized - True if this downloader is being initialized after being read from disk, false otherwise.

conflicts

public boolean conflicts(java.io.File incompleteFile)

Overrides ManagedDownloader to reserve _incompleteFile for this download. That is, any download that would use the same incomplete file is rejected, even if this is not currently downloading.

Overrides:

conflicts in class ManagedDownloader

allowAddition

protected boolean allowAddition(RemoteFileDesc other)

Overrides ManagedDownloader to allow any RemoteFileDesc that would resume from _incompleteFile.

Overrides:

allowAddition in class ManagedDownloader

getContentLength

public int getContentLength()

Overrides ManagedDownloader to display a reasonable file size even when no locations have been found.

Specified by:

getContentLength in interface Downloader

Overrides:

getContentLength in class ManagedDownloader

getFileName

public java.lang.String getFileName()

Overrides ManagedDownloader to display a reasonable file name even when no locations have been found.

Specified by:

getFileName in interface Downloader

Overrides:

getFileName in class ManagedDownloader

pauseForRequery

protected boolean pauseForRequery(int numRequeries,
                                  boolean deserializedFromDisk)
                           throws java.lang.InterruptedException

Description copied from class: ManagedDownloader

This dictates whether this downloader should wait for user input before spawning a Requery. Subclasses should override with desired behavior as necessary.

Overrides:

pauseForRequery in class ManagedDownloader

Parameters:

numRequeries - The number of requeries sent so far.

deserializedFromDisk - If the downloader was deserialized from a snapshot. May be useful for subclasses.

Returns:

true if we the pause was broken because of new results. false if the user woke us up.

Throws:

java.lang.InterruptedException

shouldInitAltLocs

protected boolean shouldInitAltLocs(boolean deserializedFromDisk)

Description copied from class: ManagedDownloader

Subclasses should override this method when necessary. If you return false, then AltLocs are not initialized from the incomplete file upon invocation of tryAllDownloads. The true case can be used when the partial file is being shared through PFS and we've learned about AltLocs we want to use.

Overrides:

shouldInitAltLocs in class ManagedDownloader

newRequery

protected QueryRequest newRequery(int numRequeries)

Overrides ManagedDownloader to use the filename and hash (if present) of the incomplete file.

Overrides:

newRequery in class ManagedDownloader

Parameters:

numRequeries - the number of requeries that have already happened

Returns:

a new QueryRequest for making the requery