private static void registerDefaultProviders() {
if (providers == null || defaultProvider == null) {
Map<String, FilePath> map = Collections.synchronizedMap(New.<String, FilePath>hashMap());
// 默认是org.h2.store.fs.FilePathDisk, 所以这里不包含它
// 但是少了org.h2.store.fs.FilePathRec、org.h2.mvstore.cache.FilePathCache
// 不过org.h2.store.fs.FilePathRec是通过org.h2.store.fs.FilePath.register(FilePath)这个方法注册
// 见org.h2.store.fs.FilePathRec.register(),
// 在org.h2.engine.ConnectionInfo.ConnectionInfo(String, Properties)调用它了
for (String c :
new String[] {
"org.h2.store.fs.FilePathDisk",
"org.h2.store.fs.FilePathMem",
"org.h2.store.fs.FilePathMemLZF",
"org.h2.store.fs.FilePathNioMem",
"org.h2.store.fs.FilePathNioMemLZF",
"org.h2.store.fs.FilePathSplit",
"org.h2.store.fs.FilePathNio",
"org.h2.store.fs.FilePathNioMapped",
"org.h2.store.fs.FilePathZip"
}) {
try {
FilePath p = (FilePath) Class.forName(c).newInstance();
map.put(p.getScheme(), p);
if (defaultProvider == null) {
defaultProvider = p;
}
} catch (Exception e) {
// ignore - the files may be excluded in purpose
}
}
providers = map;
}
}
@Override
public FileChannel open(String mode) throws IOException {
InputStream in = newInputStream();
FilePath copy = FilePath.get(getBase().toString() + ".copy");
OutputStream out = copy.newOutputStream(false);
IOUtils.copy(in, out);
FileChannel base = getBase().open(mode);
FileChannel readBase = copy.open(mode);
return new FileReorderWrites(this, base, readBase);
}
public void delete() {
for (int i = 0; ; i++) {
FilePath f = getBase(i);
if (f.exists()) {
f.delete();
} else {
break;
}
}
}
public ArrayList<FilePath> newDirectoryStream() {
List<FilePath> list = getBase().newDirectoryStream();
ArrayList<FilePath> newList = New.arrayList();
for (int i = 0, size = list.size(); i < size; i++) {
FilePath f = list.get(i);
if (!f.getName().endsWith(PART_SUFFIX)) {
newList.add(wrap(f));
}
}
return newList;
}
public void moveTo(FilePath path) {
FilePathSplit newName = (FilePathSplit) path;
for (int i = 0; ; i++) {
FilePath o = getBase(i);
if (o.exists()) {
o.moveTo(newName.getBase(i));
} else {
break;
}
}
}
public long size() {
long length = 0;
for (int i = 0; ; i++) {
FilePath f = getBase(i);
if (f.exists()) {
length += f.size();
} else {
break;
}
}
return length;
}
public boolean setReadOnly() {
boolean result = false;
for (int i = 0; ; i++) {
FilePath f = getBase(i);
if (f.exists()) {
result = f.setReadOnly();
} else {
break;
}
}
return result;
}
private FileChannel getFileChannel() throws IOException {
int id = (int) (filePointer / maxLength);
while (id >= list.length) {
int i = list.length;
FileChannel[] newList = new FileChannel[i + 1];
System.arraycopy(list, 0, newList, 0, i);
FilePath f = file.getBase(i);
newList[i] = f.open(mode);
list = newList;
}
return list[id];
}
public long lastModified() {
long lastModified = 0;
for (int i = 0; ; i++) {
FilePath f = getBase(i);
if (f.exists()) {
long l = f.lastModified();
lastModified = Math.max(lastModified, l);
} else {
break;
}
}
return lastModified;
}
public InputStream newInputStream() throws IOException {
InputStream input = getBase().newInputStream();
for (int i = 1; ; i++) {
FilePath f = getBase(i);
if (f.exists()) {
InputStream i2 = f.newInputStream();
input = new SequenceInputStream(input, i2);
} else {
break;
}
}
return input;
}
/**
* Create a new temporary file.
*
* @param suffix the suffix
* @param deleteOnExit if the file should be deleted when the virtual machine exists
* @param inTempDir if the file should be stored in the temporary directory
* @return the name of the created file
*/
public FilePath createTempFile(String suffix, boolean deleteOnExit, boolean inTempDir)
throws IOException {
while (true) {
FilePath p = getPath(name + getNextTempFileNamePart(false) + suffix);
if (p.exists() || !p.createFile()) {
// in theory, the random number could collide
getNextTempFileNamePart(true);
continue;
}
p.open("rw").close();
return p;
}
}
public FileChannel open(String mode) throws IOException {
ArrayList<FileChannel> list = New.arrayList();
list.add(getBase().open(mode));
for (int i = 1; ; i++) {
FilePath f = getBase(i);
if (f.exists()) {
list.add(f.open(mode));
} else {
break;
}
}
FileChannel[] array = new FileChannel[list.size()];
list.toArray(array);
long maxLength = array[0].size();
long length = maxLength;
if (array.length == 1) {
long defaultMaxLength = getDefaultMaxLength();
if (maxLength < defaultMaxLength) {
maxLength = defaultMaxLength;
}
} else {
if (maxLength == 0) {
closeAndThrow(0, array, array[0], maxLength);
}
for (int i = 1; i < array.length - 1; i++) {
FileChannel c = array[i];
long l = c.size();
length += l;
if (l != maxLength) {
closeAndThrow(i, array, c, maxLength);
}
}
FileChannel c = array[array.length - 1];
long l = c.size();
length += l;
if (l > maxLength) {
closeAndThrow(array.length - 1, array, c, maxLength);
}
}
return new FileSplit(this, mode, array, length, maxLength);
}
/**
* Get the file path object for the given path. Windows-style '\' is replaced with '/'.
*
* @param path the path
* @return the file path object
*/
public static FilePath get(String path) {
path = path.replace('\\', '/');
int index = path.indexOf(':');
// 如E:\\H2\\tmp\\FileStoreTest\\my.txt
// 此时index为1，所以要用FilePathDisk
// 而memFS:E:\\H2\\tmp\\FileStoreTest\\my.txt
// index是5，所以用FilePathMem
registerDefaultProviders();
if (index < 2) {
// use the default provider if no prefix or
// only a single character (drive name)
return defaultProvider.getPath(path);
}
String scheme = path.substring(0, index);
FilePath p = providers.get(scheme);
if (p == null) {
// provider not found - use the default
p = defaultProvider;
}
return p.getPath(path);
}
/**
* Register the file system.
*
* @return the instance
*/
public static FilePathReorderWrites register() {
FilePath.register(INSTANCE);
return INSTANCE;
}
/**
* Unregister a file provider.
*
* @param provider the file provider
*/
public static void unregister(FilePath provider) {
registerDefaultProviders();
providers.remove(provider.getScheme());
}
/**
* Register a file provider.
*
* @param provider the file provider
*/
public static void register(FilePath provider) {
registerDefaultProviders();
providers.put(provider.getScheme(), provider);
}
@Override
public FilePath unwrap(String fileName) {
return FilePath.get(parse(fileName)[1]);
}
/** Register this file system. */
public static void register() {
FilePath.register(new FilePathEncrypt());
}
/**
* Try to open the file.
*
* @param fileName the file name
* @param readOnly whether the file should only be opened in read-only mode, even if the file is
* writable
* @param encryptionKey the encryption key, or null if encryption is not used
*/
public void open(String fileName, boolean readOnly, char[] encryptionKey) {
if (file != null) {
return;
}
if (fileName != null) {
FilePath p = FilePath.get(fileName);
// if no explicit scheme was specified, NIO is used
if (p instanceof FilePathDisk && !fileName.startsWith(p.getScheme() + ":")) {
// ensure the NIO file system is registered
FilePathNio.class.getName();
fileName = "nio:" + fileName;
}
}
this.fileName = fileName;
FilePath f = FilePath.get(fileName);
FilePath parent = f.getParent();
if (parent != null && !parent.exists()) {
throw DataUtils.newIllegalArgumentException("Directory does not exist: {0}", parent);
}
if (f.exists() && !f.canWrite()) {
readOnly = true;
}
this.readOnly = readOnly;
try {
file = f.open(readOnly ? "r" : "rw");
if (encryptionKey != null) {
byte[] key = FilePathEncrypt.getPasswordBytes(encryptionKey);
encryptedFile = file;
file = new FilePathEncrypt.FileEncrypt(fileName, key, file);
}
file = FilePathCache.wrap(file);
try {
if (readOnly) {
fileLock = file.tryLock(0, Long.MAX_VALUE, true);
} else {
fileLock = file.tryLock();
}
} catch (OverlappingFileLockException e) {
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_FILE_LOCKED, "The file is locked: {0}", fileName, e);
}
if (fileLock == null) {
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_FILE_LOCKED, "The file is locked: {0}", fileName);
}
fileSize = file.size();
} catch (IOException e) {
throw DataUtils.newIllegalStateException(
DataUtils.ERROR_READING_FAILED, "Could not open file {0}", fileName, e);
}
}
/**
* Get the file name of a part file.
*
* @param id the part id
* @return the file name including the part id
*/
FilePath getBase(int id) {
return FilePath.get(getName(id));
}