Package org.h2.store
Class FileStore
java.lang.Object
org.h2.store.FileStore
- Direct Known Subclasses:
SecureFileStore
This class is an abstraction of a random access file.
Each file contains a magic header, and reading / writing is done in blocks.
See also
SecureFileStore
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate static final boolean
private Reference
<?> private boolean
private FileChannel
private long
private long
private final DataHandler
The callback object is responsible to check access rights, and free up disk space if required.private static final String
The magic file header.static final int
The size of the file header in bytes.private FileLock
private final String
protected String
The file name. -
Constructor Summary
ConstructorsModifierConstructorDescriptionprotected
FileStore
(DataHandler handler, String name, String mode) Create a new file using the given settings. -
Method Summary
Modifier and TypeMethodDescriptionvoid
Automatically delete the file once it is no longer in use.private void
private void
void
close()
Close the file.void
Close the file (ignoring exceptions) and delete the file.void
Close the file.private void
Just close the file, without setting the reference to null.void
Close the file without throwing any exceptions.protected byte[]
Generate the random salt bytes if required.long
Get the current location of the file pointer.void
init()
Initialize the file.protected void
initKey
(byte[] salt) Initialize the key using the given salt.long
length()
Get the file size in bytes.static FileStore
open
(DataHandler handler, String name, String mode) Open a non encrypted file store with the given settings.static FileStore
open
(DataHandler handler, String name, String mode, String cipher, byte[] key) Open an encrypted file store with the given settings.static FileStore
open
(DataHandler handler, String name, String mode, String cipher, byte[] key, int keyIterations) Open an encrypted file store with the given settings.void
openFile()
Re-open the file.void
readFully
(byte[] b, int off, int len) Read a number of bytes.void
readFullyDirect
(byte[] b, int off, int len) Read a number of bytes without decrypting.void
Release the file lock.void
seek
(long pos) Go to the specified file location.void
setCheckedWriting
(boolean value) void
setLength
(long newLength) Set the length of the file.void
No longer automatically delete the file once it is no longer in use.void
sync()
Call fsync.private static void
boolean
tryLock()
Try to lock the file.void
write
(byte[] b, int off, int len) Write a number of bytes.protected void
writeDirect
(byte[] b, int off, int len) Write a number of bytes without encrypting.
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Field Details
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HEADER_LENGTH
public static final int HEADER_LENGTHThe size of the file header in bytes.- See Also:
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HEADER
The magic file header. -
ASSERT
private static final boolean ASSERT -
name
The file name. -
handler
The callback object is responsible to check access rights, and free up disk space if required. -
file
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filePos
private long filePos -
fileLength
private long fileLength -
autoDeleteReference
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checkedWriting
private boolean checkedWriting -
mode
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lock
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Constructor Details
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FileStore
Create a new file using the given settings.- Parameters:
handler
- the callback objectname
- the file namemode
- the access mode ("r", "rw", "rws", "rwd")
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Method Details
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open
Open a non encrypted file store with the given settings.- Parameters:
handler
- the data handlername
- the file namemode
- the access mode (r, rw, rws, rwd)- Returns:
- the created object
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open
public static FileStore open(DataHandler handler, String name, String mode, String cipher, byte[] key) Open an encrypted file store with the given settings.- Parameters:
handler
- the data handlername
- the file namemode
- the access mode (r, rw, rws, rwd)cipher
- the name of the cipher algorithmkey
- the encryption key- Returns:
- the created object
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open
public static FileStore open(DataHandler handler, String name, String mode, String cipher, byte[] key, int keyIterations) Open an encrypted file store with the given settings.- Parameters:
handler
- the data handlername
- the file namemode
- the access mode (r, rw, rws, rwd)cipher
- the name of the cipher algorithmkey
- the encryption keykeyIterations
- the number of iterations the key should be hashed- Returns:
- the created object
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generateSalt
protected byte[] generateSalt()Generate the random salt bytes if required.- Returns:
- the random salt or the magic
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initKey
protected void initKey(byte[] salt) Initialize the key using the given salt.- Parameters:
salt
- the salt
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setCheckedWriting
public void setCheckedWriting(boolean value) -
checkWritingAllowed
private void checkWritingAllowed() -
checkPowerOff
private void checkPowerOff() -
init
public void init()Initialize the file. This method will write or check the file header if required. -
close
public void close()Close the file. -
closeSilently
public void closeSilently()Close the file without throwing any exceptions. Exceptions are simply ignored. -
closeAndDeleteSilently
public void closeAndDeleteSilently()Close the file (ignoring exceptions) and delete the file. -
readFullyDirect
public void readFullyDirect(byte[] b, int off, int len) Read a number of bytes without decrypting.- Parameters:
b
- the target bufferoff
- the offsetlen
- the number of bytes to read
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readFully
public void readFully(byte[] b, int off, int len) Read a number of bytes.- Parameters:
b
- the target bufferoff
- the offsetlen
- the number of bytes to read
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seek
public void seek(long pos) Go to the specified file location.- Parameters:
pos
- the location
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writeDirect
protected void writeDirect(byte[] b, int off, int len) Write a number of bytes without encrypting.- Parameters:
b
- the source bufferoff
- the offsetlen
- the number of bytes to write
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write
public void write(byte[] b, int off, int len) Write a number of bytes.- Parameters:
b
- the source bufferoff
- the offsetlen
- the number of bytes to write
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setLength
public void setLength(long newLength) Set the length of the file. This will expand or shrink the file.- Parameters:
newLength
- the new file size
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length
public long length()Get the file size in bytes.- Returns:
- the file size
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getFilePointer
public long getFilePointer()Get the current location of the file pointer.- Returns:
- the location
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sync
public void sync()Call fsync. Depending on the operating system and hardware, this may or may not in fact write the changes. -
autoDelete
public void autoDelete()Automatically delete the file once it is no longer in use. -
stopAutoDelete
public void stopAutoDelete()No longer automatically delete the file once it is no longer in use. -
closeFile
Close the file. The file may later be re-opened using openFile.- Throws:
IOException
- on failure
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closeFileSilently
private void closeFileSilently()Just close the file, without setting the reference to null. This method is called when writing failed. The reference is not set to null so that there are no NullPointerExceptions later on. -
openFile
Re-open the file. The file pointer will be reset to the previous location.- Throws:
IOException
- on failure
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trace
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tryLock
public boolean tryLock()Try to lock the file.- Returns:
- true if successful
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releaseLock
public void releaseLock()Release the file lock.
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