/**
* Returns the number of volumes contained in this partition.
*
* <p>If the total list of volumes or volume names have already been collected (see {@link
* #getVolumes()}), then the returning value will be calculated based upon the current list.
* Otherwise, AFS will be explicitly queried for the information.
*
* <p>The product of this method is not saved, and is recalculated with every call.
*
* @return the number of volumes contained in this partition.
* @exception AFSException If an error occurs in any of the associated native methods
*/
public int getVolumeCount() throws AFSException {
if (volumes != null) {
return volumes.size();
} else if (volumeNames != null) {
return volumeNames.size();
} else {
return getVolumeCount(cell.getCellHandle(), server.getVosHandle(), getID());
}
}
/**
* Obtains the most current list of volume names of this partition.
*
* @exception AFSException If an error occurs in the native code
*/
protected void refreshVolumeNames() throws AFSException {
String currName;
long iterationID = getVolumesBegin(cell.getCellHandle(), server.getVosHandle(), getID());
volumeNames = new ArrayList();
while ((currName = getVolumesNextString(iterationID)) != null) {
volumeNames.add(currName);
}
getVolumesDone(iterationID);
}
/**
* Obtains the most current list of <code>Volume</code> objects of this partition.
*
* @exception AFSException If an error occurs in the native code
*/
protected void refreshVolumes() throws AFSException {
Volume currVolume;
long iterationID = getVolumesBegin(cell.getCellHandle(), server.getVosHandle(), getID());
volumes = new ArrayList();
currVolume = new Volume(this);
while (getVolumesNext(iterationID, currVolume) != 0) {
volumes.add(currVolume);
currVolume = new Volume(this);
}
getVolumesDone(iterationID);
}
/**
* Salvages (restores consistency to) this partition. Uses default values for most salvager
* options in order to simplify the API.
*
* @exception AFSException If an error occurs in the native code
*/
public void salvage() throws AFSException {
server.salvage(
cell.getCellHandle(),
server.getBosHandle(),
name,
null,
4,
null,
null,
false,
false,
false,
false,
false,
false);
}
/**
* Returns an array containing a subset of the names of volumes associated with this <code>
* Partition</code>. The subset is a point-in-time list of volume names starting at the complete
* array's index of <code>startIndex</code> and containing up to <code>length</code> elements.
*
* <p>If <code>length</code> is larger than the number of remaining elements, respective to <code>
* startIndex</code>, then this method will ignore the remaining positions requested by <code>
* length</code> and return an array that contains the remaining number of elements found in this
* partition's complete array of volume names.
*
* <p>This method is especially useful when managing iterations of very large lists. {@link
* #getVolumeCount()} can be used to determine if iteration management is practical.
*
* <p>This method does not save the resulting data and therefore queries AFS for each call.
*
* <p><B>Example:</B> If there are more than 50,000 volumes within this partition then only render
* them in increments of 10,000.
*
* <PRE>
* ...
* String[] volumes;
* if (partition.getVolumeCount() > 50000) {
* int index = 0;
* int length = 10000;
* while (index < partition.getVolumeCount()) {
* volumes = partition.<B>getVolumeNames</B>(index, length);
* for (int i = 0; i < volumes.length; i++) {
* ...
* }
* index += length;
* ...
* }
* } else {
* volumes = partition.getVolumeNames();
* for (int i = 0; i < volumes.length; i++) {
* ...
* }
* }
* ...
* </PRE>
*
* @param startIndex the base zero index position at which the subset array should start from,
* relative to the complete list of elements present in AFS.
* @param length the number of elements that the subset should contain
* @return a subset array of volume names hosted by this partition
* @exception AFSException If an error occurs in the native code
* @see #getVolumeCount()
* @see #getVolumes(int, int)
* @see #getVolumes()
*/
public String[] getVolumeNames(int startIndex, int length) throws AFSException {
String[] volumes = new String[length];
String currName;
int i = 0;
long iterationID =
getVolumesBeginAt(cell.getCellHandle(), server.getVosHandle(), getID(), startIndex);
while ((currName = getVolumesNextString(iterationID)) != null && i < length) {
volumes[i] = currName;
i++;
}
getVolumesDone(iterationID);
if (i < length) {
String[] v = new String[i];
System.arraycopy(volumes, 0, v, 0, i);
return v;
} else {
return volumes;
}
}
/**
* Returns an array containing a subset of the <code>Volume</code> objects associated with this
* <code>Partition</code>, each of which is an abstract representation of an actual AFS volume of
* the AFS partition. The subset is a point-in-time list of volumes (<code>Volume</code> objects
* representing AFS volumes) starting at the complete array's index of <code>startIndex</code> and
* containing up to <code>length</code> elements.
*
* <p>If <code>length</code> is larger than the number of remaining elements, respective to <code>
* startIndex</code>, then this method will ignore the remaining positions requested by <code>
* length</code> and return an array that contains the remaining number of elements found in this
* partition's complete array of volumes.
*
* <p>This method is especially useful when managing iterations of very large lists. {@link
* #getVolumeCount()} can be used to determine if iteration management is practical.
*
* <p>This method does not save the resulting data and therefore queries AFS for each call.
*
* <p><B>Example:</B> If there are more than 50,000 volumes within this partition then only render
* them in increments of 10,000.
*
* <PRE>
* ...
* Volume[] volumes;
* if (partition.getVolumeCount() > 50000) {
* int index = 0;
* int length = 10000;
* while (index < partition.getVolumeCount()) {
* volumes = partition.<B>getVolumes</B>(index, length);
* for (int i = 0; i < volumes.length; i++) {
* ...
* }
* index += length;
* ...
* }
* } else {
* volumes = partition.getVolumes();
* for (int i = 0; i < volumes.length; i++) {
* ...
* }
* }
* ...
* </PRE>
*
* @param startIndex the base zero index position at which the subset array should start from,
* relative to the complete list of elements present in AFS.
* @param length the number of elements that the subset should contain
* @return a subset array of volumes hosted by this partition
* @exception AFSException If an error occurs in the native code
* @see #getVolumeCount()
* @see #getVolumeNames(int, int)
* @see #getVolumes()
*/
public Volume[] getVolumes(int startIndex, int length) throws AFSException {
Volume[] volumes = new Volume[length];
Volume currVolume = new Volume(this);
int i = 0;
long iterationID =
getVolumesBeginAt(cell.getCellHandle(), server.getVosHandle(), getID(), startIndex);
while (getVolumesNext(iterationID, currVolume) != 0 && i < length) {
volumes[i] = currVolume;
currVolume = new Volume(this);
i++;
}
getVolumesDone(iterationID);
if (i < length) {
Volume[] v = new Volume[i];
System.arraycopy(volumes, 0, v, 0, i);
return v;
} else {
return volumes;
}
}
/**
* Syncs the VLDB to this partition.
*
* @exception AFSException If an error occurs in the native code
*/
public void syncVLDB() throws AFSException {
server.syncVLDBWithServer(cell.getCellHandle(), server.getVosHandle(), getID(), false);
}
/**
* Syncs this partition to the VLDB.
*
* @exception AFSException If an error occurs in the native code
*/
public void syncPartition() throws AFSException {
server.syncServerWithVLDB(cell.getCellHandle(), server.getVosHandle(), getID());
}
/**
* Refreshes the information fields of this <code>Partition</code> to reflect the current state of
* the AFS partition. These include total free space, id, etc.
*
* @exception AFSException If an error occurs in the native code
*/
protected void refreshInfo() throws AFSException {
getPartitionInfo(cell.getCellHandle(), server.getVosHandle(), getID(), this);
cachedInfo = true;
}
