/**
* Sets the length.
*
* @param length The length to set
*/
public synchronized void setLength(long length) throws IOException {
if (getFileSystem().isReadOnly()) {
throw new ReadOnlyFileSystemException("setLength in readonly filesystem");
}
if (this.length == length) {
// Do nothing
return;
}
final FatFileSystem fs = getFatFileSystem();
final Fat fat = fs.getFat();
final int nrClusters = (int) ((length + clusterSize - 1) / clusterSize);
if (this.length == 0) {
final long[] chain = fat.allocNew(nrClusters);
this.startCluster = chain[0];
this.myEntry.setStartCluster((int) startCluster);
} else {
final long[] chain = fs.getFat().getChain(startCluster);
if (nrClusters != chain.length) {
if (nrClusters > chain.length) {
// Grow
int count = nrClusters - chain.length;
while (count > 0) {
fat.allocAppend(getStartCluster());
count--;
}
} else {
// Shrink
fat.setEof(chain[nrClusters - 1]);
for (int i = nrClusters; i < chain.length; i++) {
fat.setFree(chain[i]);
}
}
}
}
this.length = length;
this.myEntry.updateLength(length);
}
