/**
* Allocates the requested space in the file.
*
* @param len requested space
* @return allocated file position and length as FileEntry object
*/
private FileEntry allocate(int len) {
synchronized (freeList) {
// lookup a free entry of sufficient size
SortedSet<FileEntry> candidates = freeList.tailSet(new FileEntry(0, len));
for (Iterator<FileEntry> it = candidates.iterator(); it.hasNext(); ) {
FileEntry free = it.next();
// ignore entries that are still in use by concurrent readers
if (free.isLocked()) continue;
// There's no race condition risk between locking the entry on
// loading and checking whether it's locked (or store allocation),
// because for the entry to be lockable, it needs to be in the
// entries collection, in which case it's not in the free list.
// The only way an entry can be found in the free list is if it's
// been removed, and to remove it, lock on "entries" needs to be
// acquired, which is also a pre-requisite for loading data.
// found one, remove from freeList
it.remove();
return allocateExistingEntry(free, len);
}
// no appropriate free section available, append at end of file
FileEntry fe = new FileEntry(filePos, len);
filePos += len;
if (trace)
log.tracef(
"New entry allocated at %d:%d, %d free entries, file size is %d",
fe.offset, fe.size, freeList.size(), filePos);
return fe;
}
}
/**
* 创建Zipper对象
*
* @param out 输出流
* @param filter 文件过滤，不过滤可以为null。
* @param srcFilename 源文件名。可以有多个源文件，如果源文件是目录，那么所有子目录都将被包含。
*/
protected Zipper(OutputStream out, List<FileEntry> fileEntrys, String encoding) {
Assert.notEmpty(fileEntrys);
long begin = System.currentTimeMillis();
log.debug("开始制作压缩包");
try {
try {
zipOut = new ZipOutputStream(out);
if (!StringUtils.isBlank(encoding)) {
log.debug("using encoding: {}", encoding);
zipOut.setEncoding(encoding);
} else {
log.debug("using default encoding");
}
for (FileEntry fe : fileEntrys) {
zip(fe.getFile(), fe.getFilter(), fe.getZipEntry(), fe.getPrefix());
}
} finally {
zipOut.close();
}
} catch (IOException e) {
throw new RuntimeException("制作压缩包时，出现IO异常！", e);
}
long end = System.currentTimeMillis();
log.info("制作压缩包成功。耗时：{}ms。", end - begin);
}
@Override
public View getView(final int position, final View convertView, final ViewGroup parent) {
// We need to get the best view (re-used if possible) and then
// retrieve its corresponding ViewHolder, which optimizes lookup efficiency
final View view = getWorkingView(convertView);
final ViewHolder viewHolder = getViewHolder(view);
final FileEntry entry = getItem(position);
// Setting the title view is straightforward
viewHolder.titleView.setText(entry.getFilename());
// Setting the subTitle view requires a tiny bit of formatting
final String formattedSubTitle =
String.format(
"By %s on %s",
entry.getAuthor(),
DateFormat.getDateInstance(DateFormat.SHORT).format(entry.getPostDate()));
viewHolder.subTitleView.setText(formattedSubTitle);
// Setting image view is also simple
viewHolder.imageView.setImageResource(entry.getIcon());
return view;
}
@Override
public void clear() {
resizeLock.writeLock().lock();
try {
synchronized (entries) {
synchronized (freeList) {
// wait until all readers are done reading file entries
for (FileEntry fe : entries.values()) fe.waitUnlocked();
for (FileEntry fe : freeList) fe.waitUnlocked();
// clear in-memory state
entries.clear();
freeList.clear();
// reset file
if (trace) log.tracef("Truncating file, current size is %d", filePos);
channel.truncate(0);
channel.write(ByteBuffer.wrap(MAGIC), 0);
filePos = MAGIC.length;
}
}
} catch (Exception e) {
throw new PersistenceException(e);
} finally {
resizeLock.writeLock().unlock();
}
}
/**
* Coalesces adjacent free entries to create larger free entries (so that the probability of
* finding a free entry during allocation increases)
*/
private void mergeFreeEntries(List<FileEntry> entries) {
long startTime = 0;
if (trace) startTime = timeService.wallClockTime();
FileEntry lastEntry = null;
FileEntry newEntry = null;
int mergeCounter = 0;
for (Iterator<FileEntry> it = entries.iterator(); it.hasNext(); ) {
FileEntry fe = it.next();
if (fe.isLocked()) {
continue;
}
// Merge any holes created (consecutive free entries) in the file
if ((lastEntry != null) && (lastEntry.offset == (fe.offset + fe.size))) {
if (newEntry == null) {
newEntry = new FileEntry(fe.offset, fe.size + lastEntry.size);
freeList.remove(lastEntry);
mergeCounter++;
} else {
newEntry = new FileEntry(fe.offset, fe.size + newEntry.size);
}
freeList.remove(fe);
mergeCounter++;
} else {
if (newEntry != null) {
try {
addNewFreeEntry(newEntry);
if (trace)
log.tracef(
"Merged %d entries at %d:%d, %d free entries",
mergeCounter, newEntry.offset, newEntry.size, freeList.size());
} catch (IOException e) {
throw new PersistenceException("Could not add new merged entry", e);
}
newEntry = null;
mergeCounter = 0;
}
}
lastEntry = fe;
}
if (newEntry != null) {
try {
addNewFreeEntry(newEntry);
if (trace)
log.tracef(
"Merged %d entries at %d:%d, %d free entries",
mergeCounter, newEntry.offset, newEntry.size, freeList.size());
} catch (IOException e) {
throw new PersistenceException("Could not add new merged entry", e);
}
}
if (trace)
log.tracef(
"Total time taken for mergeFreeEntries: "
+ (timeService.wallClockTime() - startTime)
+ " (ms)");
}
/**
* Initialize the observer.
*
* @throws Exception if an error occurs
*/
public void initialize() throws Exception {
rootEntry.refresh(rootEntry.getFile());
File[] files = listFiles(rootEntry.getFile());
FileEntry[] children = files.length > 0 ? new FileEntry[files.length] : FileEntry.EMPTY_ENTRIES;
for (int i = 0; i < files.length; i++) {
children[i] = createFileEntry(rootEntry, files[i]);
}
rootEntry.setChildren(children);
}
/**
* Fire directory/file delete events to the registered listeners.
*
* @param entry The file entry
*/
private void doDelete(FileEntry entry) {
for (FileAlterationListener listener : listeners) {
if (entry.isDirectory()) {
listener.onDirectoryDelete(entry.getFile());
} else {
listener.onFileDelete(entry.getFile());
}
}
}
/**
* Create a new file entry for the specified file.
*
* @param parent The parent file entry
* @param file The file to create an entry for
* @return A new file entry
*/
private FileEntry createFileEntry(FileEntry parent, File file) {
FileEntry entry = parent.newChildInstance(file);
entry.refresh(file);
File[] files = listFiles(file);
FileEntry[] children = files.length > 0 ? new FileEntry[files.length] : FileEntry.EMPTY_ENTRIES;
for (int i = 0; i < files.length; i++) {
children[i] = createFileEntry(entry, files[i]);
}
entry.setChildren(children);
return entry;
}
/**
* Fire directory/file change events to the registered listeners.
*
* @param entry The previous file system entry
* @param file The current file
*/
private void doMatch(FileEntry entry, File file) {
if (entry.refresh(file)) {
for (FileAlterationListener listener : listeners) {
if (entry.isDirectory()) {
listener.onDirectoryChange(file);
} else {
listener.onFileChange(file);
}
}
}
}
/**
* Fire directory/file created events to the registered listeners.
*
* @param entry The file entry
*/
private void doCreate(FileEntry entry) {
for (FileAlterationListener listener : listeners) {
if (entry.isDirectory()) {
listener.onDirectoryCreate(entry.getFile());
} else {
listener.onFileCreate(entry.getFile());
}
}
FileEntry[] children = entry.getChildren();
for (FileEntry aChildren : children) {
doCreate(aChildren);
}
}
void assertFileEntryEquals(FileEntry actual, FileEntry expected) {
assertEquals(
actual.getType(), expected.getType(), "The first column, the entry type, is wrong");
assertEquals(
actual.getNewSHA(), expected.getNewSHA(), "The second column, the new SHA-256, is wrong");
assertEquals(
actual.getOldSHA(), expected.getOldSHA(), "The third column, the old SHA-256, is wrong");
assertEquals(
actual.getFile(), expected.getFile(), "The fourth column, the file name, is wrong");
}
@Override
public void purge(Executor threadPool, final PurgeListener task) {
long now = timeService.wallClockTime();
List<KeyValuePair<Object, FileEntry>> entriesToPurge =
new ArrayList<KeyValuePair<Object, FileEntry>>();
synchronized (entries) {
for (Iterator<Map.Entry<K, FileEntry>> it = entries.entrySet().iterator(); it.hasNext(); ) {
Map.Entry<K, FileEntry> next = it.next();
FileEntry fe = next.getValue();
if (fe.isExpired(now)) {
it.remove();
entriesToPurge.add(new KeyValuePair<Object, FileEntry>(next.getKey(), fe));
}
}
}
resizeLock.readLock().lock();
try {
for (Iterator<KeyValuePair<Object, FileEntry>> it = entriesToPurge.iterator();
it.hasNext(); ) {
KeyValuePair<Object, FileEntry> next = it.next();
FileEntry fe = next.getValue();
if (fe.isExpired(now)) {
it.remove();
try {
free(fe);
} catch (Exception e) {
throw new PersistenceException(e);
}
if (task != null) task.entryPurged(next.getKey());
}
}
// Disk space optimizations
synchronized (freeList) {
processFreeEntries();
}
} finally {
resizeLock.readLock().unlock();
}
}
/**
* Compare two file lists for files which have been created, modified or deleted.
*
* @param parent The parent entry
* @param previous The original list of files
* @param files The current list of files
*/
private void checkAndNotify(FileEntry parent, FileEntry[] previous, File[] files) {
int c = 0;
FileEntry[] current = files.length > 0 ? new FileEntry[files.length] : FileEntry.EMPTY_ENTRIES;
for (FileEntry entry : previous) {
while (c < files.length && comparator.compare(entry.getFile(), files[c]) > 0) {
current[c] = createFileEntry(parent, files[c]);
doCreate(current[c]);
c++;
}
if (c < files.length && comparator.compare(entry.getFile(), files[c]) == 0) {
doMatch(entry, files[c]);
checkAndNotify(entry, entry.getChildren(), listFiles(files[c]));
current[c] = entry;
c++;
} else {
checkAndNotify(entry, entry.getChildren(), FileUtils.EMPTY_FILE_ARRAY);
doDelete(entry);
}
}
for (; c < files.length; c++) {
current[c] = createFileEntry(parent, files[c]);
doCreate(current[c]);
}
parent.setChildren(current);
}
/** Check whether the file and its chlidren have been created, modified or deleted. */
public void checkAndNotify() {
/* fire onStart() */
for (FileAlterationListener listener : listeners) {
listener.onStart(this);
}
/* fire directory/file events */
File rootFile = rootEntry.getFile();
if (rootFile.exists()) {
checkAndNotify(rootEntry, rootEntry.getChildren(), listFiles(rootFile));
} else if (rootEntry.isExists()) {
checkAndNotify(rootEntry, rootEntry.getChildren(), FileUtils.EMPTY_FILE_ARRAY);
} else {
// Didn't exist and still doesn't
}
/* fire onStop() */
for (FileAlterationListener listener : listeners) {
listener.onStop(this);
}
}
/** Removes free entries towards the end of the file and truncates the file. */
private void truncateFile(List<FileEntry> entries) {
long startTime = 0;
if (trace) startTime = timeService.wallClockTime();
int reclaimedSpace = 0;
int removedEntries = 0;
long truncateOffset = -1;
for (Iterator<FileEntry> it = entries.iterator(); it.hasNext(); ) {
FileEntry fe = it.next();
// Till we have free entries at the end of the file,
// we can remove them and contract the file to release disk
// space.
if (!fe.isLocked() && ((fe.offset + fe.size) == filePos)) {
truncateOffset = fe.offset;
filePos = fe.offset;
freeList.remove(fe);
it.remove();
reclaimedSpace += fe.size;
removedEntries++;
} else {
break;
}
}
if (truncateOffset > 0) {
try {
channel.truncate(truncateOffset);
} catch (IOException e) {
throw new PersistenceException("Error while truncating file", e);
}
}
if (trace) {
log.tracef("Removed entries: " + removedEntries + ", Reclaimed Space: " + reclaimedSpace);
log.tracef(
"Time taken for truncateFile: " + (timeService.wallClockTime() - startTime) + " (ms)");
}
}
private MarshalledEntry<K, V> _load(Object key, boolean loadValue, boolean loadMetadata) {
final FileEntry fe;
resizeLock.readLock().lock();
try {
synchronized (entries) {
// lookup FileEntry of the key
fe = entries.get(key);
if (fe == null) return null;
// Entries are removed due to expiration from {@link SingleFileStore#purge}
if (fe.isExpired(timeService.wallClockTime())) {
return null;
} else {
// lock entry for reading before releasing entries monitor
fe.lock();
}
}
} finally {
resizeLock.readLock().unlock();
}
org.infinispan.commons.io.ByteBuffer valueBb = null;
org.infinispan.commons.io.ByteBuffer metadataBb = null;
// If we only require the key, then no need to read disk
if (!loadValue && !loadMetadata) {
try {
return ctx.getMarshalledEntryFactory().newMarshalledEntry(key, valueBb, metadataBb);
} finally {
fe.unlock();
}
}
final byte[] data;
try {
// load serialized data from disk
data = new byte[fe.keyLen + fe.dataLen + (loadMetadata ? fe.metadataLen : 0)];
// The entry lock will prevent clear() from truncating the file at this point
channel.read(ByteBuffer.wrap(data), fe.offset + KEY_POS);
} catch (Exception e) {
throw new PersistenceException(e);
} finally {
// No need to keep the lock for deserialization.
// FileEntry is immutable, so its members can't be changed by another thread.
fe.unlock();
}
if (trace) log.tracef("Read entry %s at %d:%d", key, fe.offset, fe.actualSize());
ByteBufferFactory factory = ctx.getByteBufferFactory();
org.infinispan.commons.io.ByteBuffer keyBb = factory.newByteBuffer(data, 0, fe.keyLen);
if (loadValue) {
valueBb = factory.newByteBuffer(data, fe.keyLen, fe.dataLen);
}
if (loadMetadata && fe.metadataLen > 0) {
metadataBb = factory.newByteBuffer(data, fe.keyLen + fe.dataLen, fe.metadataLen);
}
return ctx.getMarshalledEntryFactory().newMarshalledEntry(keyBb, valueBb, metadataBb);
}
/**
* Construct an observer for the specified directory, file filter and file comparator.
*
* @param rootEntry the root directory to observe
* @param fileFilter The file filter or null if none
* @param caseSensitivity what case sensitivity to use comparing file names, null means system
* sensitive
*/
protected FileAlterationObserver(
FileEntry rootEntry, FileFilter fileFilter, IOCase caseSensitivity) {
if (rootEntry == null) {
throw new IllegalArgumentException("Root entry is missing");
}
if (rootEntry.getFile() == null) {
throw new IllegalArgumentException("Root directory is missing");
}
this.rootEntry = rootEntry;
this.fileFilter = fileFilter;
if (caseSensitivity == null || caseSensitivity.equals(IOCase.SYSTEM)) {
this.comparator = NameFileComparator.NAME_SYSTEM_COMPARATOR;
} else if (caseSensitivity.equals(IOCase.INSENSITIVE)) {
this.comparator = NameFileComparator.NAME_INSENSITIVE_COMPARATOR;
} else {
this.comparator = NameFileComparator.NAME_COMPARATOR;
}
}
/**
* The base class implementation calls {@link #load(Object)} for this, we can do better because we
* keep all keys in memory.
*/
@Override
public boolean contains(Object key) {
FileEntry entry = entries.get(key);
return entry != null && !entry.isExpired(timeService.wallClockTime());
}
/**
* Return the directory being observed.
*
* @return the directory being observed
*/
public File getDirectory() {
return rootEntry.getFile();
}
