/// <summary>
/// Initializes the Value Queues for the provided keys by calling the
/// fill Method with "numInitValues" values
/// </summary>
/// <param name="keyNames">Array of key Names</param>
/// <exception cref="ExecutionException"/>
public virtual void InitializeQueuesForKeys(params string[] keyNames)
{
foreach (string keyName in keyNames)
{
keyQueues.Get(keyName);
}
}
/// <summary>
/// Obtains the file status, first by checking the stat cache if it is
/// available, and then by getting it explicitly from the filesystem.
/// </summary>
/// <remarks>
/// Obtains the file status, first by checking the stat cache if it is
/// available, and then by getting it explicitly from the filesystem. If we got
/// the file status from the filesystem, it is added to the stat cache.
/// The stat cache is expected to be managed by callers who provided it to
/// FSDownload.
/// </remarks>
/// <exception cref="System.IO.IOException"/>
private static FileStatus GetFileStatus(FileSystem fs, Path path, LoadingCache <Path
, Future <FileStatus> > statCache)
{
// if the stat cache does not exist, simply query the filesystem
if (statCache == null)
{
return(fs.GetFileStatus(path));
}
try
{
// get or load it from the cache
return(statCache.Get(path).Get());
}
catch (ExecutionException e)
{
Exception cause = e.InnerException;
// the underlying exception should normally be IOException
if (cause is IOException)
{
throw (IOException)cause;
}
else
{
throw new IOException(cause);
}
}
catch (Exception e)
{
// should not happen
Sharpen.Thread.CurrentThread().Interrupt();
throw new IOException(e);
}
}
/// <summary>Get the group memberships of a given user.</summary>
/// <remarks>
/// Get the group memberships of a given user.
/// If the user's group is not cached, this method may block.
/// </remarks>
/// <param name="user">User's name</param>
/// <returns>the group memberships of the user</returns>
/// <exception cref="System.IO.IOException">if user does not exist</exception>
public virtual IList <string> GetGroups(string user)
{
// No need to lookup for groups of static users
IList <string> staticMapping = staticUserToGroupsMap[user];
if (staticMapping != null)
{
return(staticMapping);
}
// Check the negative cache first
if (IsNegativeCacheEnabled())
{
if (negativeCache.Contains(user))
{
throw NoGroupsForUser(user);
}
}
try
{
return(cache.Get(user));
}
catch (ExecutionException e)
{
throw (IOException)e.InnerException;
}
}
internal virtual DFSClient GetDfsClient(string userName)
{
DFSClient client = null;
try
{
client = clientCache.Get(userName);
}
catch (ExecutionException e)
{
Log.Error("Failed to create DFSClient for user:"******" Cause:" + e);
}
return(client);
}
internal virtual FSDataInputStream GetDfsInputStream(string userName, string inodePath
)
{
DFSClientCache.DFSInputStreamCaheKey k = new DFSClientCache.DFSInputStreamCaheKey
(userName, inodePath);
FSDataInputStream s = null;
try
{
s = inputstreamCache.Get(k);
}
catch (ExecutionException e)
{
Log.Warn("Failed to create DFSInputStream for user:"******" Cause:" + e);
}
return(s);
}