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FileDownloadCache

public class FileDownloadCache
extends Object

java.lang.Object
↳	com.android.tradefed.build.FileDownloadCache

A helper class that maintains a local filesystem LRU cache of downloaded files.

Summary

Public methods
`void`	`deleteCacheEntry(String remoteFilePath)` Allow deleting an entry from the cache.
`void`	`fetchRemoteFile(IFileDownloader downloader, String remoteFilePath, File destFile)` Download the file or link the cache to the destination file.
`File`	`fetchRemoteFile(IFileDownloader downloader, String remoteFilePath)` Returns a local file corresponding to the given `remotePath` The local `ERROR(/File)` will be copied from the cache if it exists, otherwise will be downloaded via the given `IFileDownloader`.
`void`	`setMaxCacheSize(long numBytes)` Set the maximum size of the local file cache.

Protected methods
`void`	`lockFile(String remoteFilePath)` Acquires the lock for a file.
`boolean`	`tryLockFile(String remoteFilePath)` Acquire the lock for a file only if it is not held by another thread.
`void`	`unlockFile(String remoteFilePath)` Attempt to release a lock for a file.

Public methods

deleteCacheEntry

public void deleteCacheEntry (String remoteFilePath)

Allow deleting an entry from the cache. In case the entry is invalid or corrupted.

Parameters
`remoteFilePath`	`String`

fetchRemoteFile

public void fetchRemoteFile (IFileDownloader downloader, 
                String remoteFilePath, 
                File destFile)

Download the file or link the cache to the destination file.

Parameters
`downloader`	`IFileDownloader`: the `IFileDownloader`
`remoteFilePath`	`String`: the remote file.
`destFile`	`File`: The destination file of the download.

Throws
	com.android.tradefed.build.BuildRetrievalError
`BuildRetrievalError`

fetchRemoteFile

public File fetchRemoteFile (IFileDownloader downloader, 
                String remoteFilePath)

Returns a local file corresponding to the given remotePath

The local ERROR(/File) will be copied from the cache if it exists, otherwise will be downloaded via the given IFileDownloader.

Parameters
`downloader`	`IFileDownloader`: the `IFileDownloader`
`remoteFilePath`	`String`: the remote file.

Returns
`File`	a local `ERROR(/File)` containing contents of remotePath

Throws
`BuildRetrievalError`	if file could not be retrieved

setMaxCacheSize

public void setMaxCacheSize (long numBytes)

Set the maximum size of the local file cache.

Cache will not be adjusted immediately if set to a smaller size than current, but will take effect on next file download.

Protected methods

lockFile

protected void lockFile (String remoteFilePath)

Acquires the lock for a file.

Parameters
`remoteFilePath`	`String`

tryLockFile

protected boolean tryLockFile (String remoteFilePath)

Acquire the lock for a file only if it is not held by another thread.

Parameters
`remoteFilePath`	`String`

Returns
`boolean`	true if the lock was acquired, and false otherwise.

unlockFile

protected void unlockFile (String remoteFilePath)

Attempt to release a lock for a file.

Parameters
`remoteFilePath`	`String`