uk.ac.rdg.resc.jstyx.server
Class URLFile

java.lang.Object
  uk.ac.rdg.resc.jstyx.server.StyxFile
      uk.ac.rdg.resc.jstyx.server.URLFile

public class URLFile
extends StyxFile

StyxFile that contains a URL.

Author:

Jon Blower $Revision: 609 $ $Date: 2006-03-31 18:09:42 +0100 (Fri, 31 Mar 2006) $ $Log$ Revision 1.3 2005/11/07 21:14:44 jonblower Fixed null pointer bug in getLength() Revision 1.2 2005/11/07 12:22:25 jonblower Added getLength() method Revision 1.1 2005/11/04 17:32:11 jonblower Initial import

Field Summary

Fields inherited from class uk.ac.rdg.resc.jstyx.server.StyxFile

auth, directory, lastModifiedTime, name, parent

Constructor Summary

URLFile(java.lang.String name)
Creates a new instance of URLFile with read-write permissions for everyone (0666).

Method Summary

ULong	getLength()
java.net.URL	getURL()
void	read(StyxFileClient client, long offset, int count, int tag) Reads data from this file.
void	write(StyxFileClient client, long offset, int count, org.apache.mina.common.ByteBuffer data, boolean truncate, int tag) The new value for the URL must come in a single message (i.e.

Methods inherited from class uk.ac.rdg.resc.jstyx.server.StyxFile

addChangeListener, addClient, checkSetLastModifiedTime, checkSetLength, checkSetMode, checkSetName, clientConnected, clientDisconnected, contentsChanged, delete, fireContentsChanged, getClient, getDirEntry, getFullPath, getGroup, getName, getNumClients, getOwner, getParent, getPermissions, getQid, getVersion, incrementVersion, isAppendOnly, isAuth, isDirectory, isExclusive, processAndReplyRead, processAndReplyRead, processAndReplyRead, refresh, remove, removeChangeListener, removeClient, rename, replyRead, replyRead, replyRead, replyRead, replyRead, replyWrite, setLastAccessTime, setLastModified, setLength, setMode, setName, setPermissions, setReadOnly

Methods inherited from class java.lang.Object

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

Constructor Detail

URLFile

public URLFile(java.lang.String name)
        throws StyxException

Creates a new instance of URLFile with read-write permissions for everyone (0666).

Throws:

StyxException

Method Detail

read

public void read(StyxFileClient client,
                 long offset,
                 int count,
                 int tag)
          throws StyxException

Description copied from class: StyxFile

Reads data from this file. This method could be synchronized in subclasses, but watch out for blocks if the read is expected to take some time to complete. Subclasses must make sure they reply to the read request by creating a java.nio.ByteBuffer or byte array of data, then calling the appropriate readReply() (this can be done at any time; it does not have to be done within the read() method). This default implementation simply throws a StyxException, which will result in an Rerror message being sent back to the client. Subclasses should override this to provide the desired behaviour when the file is read.

Overrides:

read in class StyxFile

Parameters:

client - The client that is performing the read

offset - The point in the file at which to start reading

count - The maximum number of bytes to read

tag - The tag of the incoming Tread message (this is needed when calling readReply())

Throws:

StyxException

write

public void write(StyxFileClient client,
                  long offset,
                  int count,
                  org.apache.mina.common.ByteBuffer data,
                  boolean truncate,
                  int tag)
           throws StyxException

The new value for the URL must come in a single message (i.e. the offset must be zero and the incoming ByteBuffer must contain the entire URL). Must also write with truncation.

Overrides:

write in class StyxFile

Parameters:

client - The client that is performing the write operation

offset - The place in the file where the new data will be added

count - The number of bytes to write

data - The data to write. The position and limit of this ByteBuffer will be set correctly, but subclasses should note that the position might not be zero.

truncate - If this is true the file will be truncated at the end of the new data

tag - The tag of the incoming Twrite message (this is needed when calling writeReply())

Throws:

StyxException

getLength

public ULong getLength()

Overrides:

getLength in class StyxFile

Returns:

the size of this file in bytes

getURL

public java.net.URL getURL()

Returns:

the URL contained in this file or null if it hasn't been set