org.h2.store.fs
Class FileSystemMemory

java.lang.Object
  org.h2.store.fs.FileSystem
      org.h2.store.fs.FileSystemMemory

public class FileSystemMemory
extends FileSystem

This file system keeps files fully in memory. There is an option to compress file blocks to safe memory.

Field Summary

static java.lang.String	PREFIX The prefix used for an in-memory file system.
static java.lang.String	PREFIX_LZF The prefix used for a compressed in-memory file system.

Method Summary

protected boolean	accepts(java.lang.String fileName) Check if the file system is responsible for this file name.
boolean	canWrite(java.lang.String fileName) Check if the file is writable.
void	copy(java.lang.String source, java.lang.String target) Copy a file from one directory to another, or to another file.
void	createDirs(java.lang.String fileName) Create all required directories that are required for this file.
boolean	createNewFile(java.lang.String fileName) Create a new file.
void	delete(java.lang.String fileName) Delete a file.
void	deleteRecursive(java.lang.String fileName, boolean tryOnly) Delete a directory or file and all subdirectories and files.
boolean	exists(java.lang.String fileName) Checks if a file exists.
boolean	fileStartsWith(java.lang.String fileName, java.lang.String prefix) Check if a file starts with a given prefix.
java.lang.String	getCanonicalPath(java.lang.String fileName) Normalize a file name.
java.lang.String	getFileName(java.lang.String name) Get the file name (without directory part).
static FileSystemMemory	getInstance()
long	getLastModified(java.lang.String fileName) Get the last modified date of a file
java.lang.String	getParent(java.lang.String fileName) Get the parent directory of a file or directory.
boolean	isAbsolute(java.lang.String fileName) Check if the file name includes a path.
boolean	isDirectory(java.lang.String fileName) Check if it is a file or a directory.
boolean	isReadOnly(java.lang.String fileName) Check if a file is read-only.
long	length(java.lang.String fileName) Get the length of a file.
java.lang.String[]	listFiles(java.lang.String path) List the files in the given directory.
java.io.InputStream	openFileInputStream(java.lang.String fileName) Create an input stream to read from the file.
FileObject	openFileObject(java.lang.String fileName, java.lang.String mode) Open a random access file object.
java.io.OutputStream	openFileOutputStream(java.lang.String fileName, boolean append) Create an output stream to write into the file.
void	rename(java.lang.String oldName, java.lang.String newName) Rename a file if this is allowed.
boolean	setReadOnly(java.lang.String fileName) Disable the ability to write.
boolean	tryDelete(java.lang.String fileName) Try to delete a file.
java.lang.String	unwrap(java.lang.String fileName) Get the unwrapped file name (without wrapper prefixes if wrapping / delegating file systems are used).

Methods inherited from class org.h2.store.fs.FileSystem

createTempFile, getInstance, getNextTempFileNamePart, mkdirs, register, unregister

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

PREFIX

public static final java.lang.String PREFIX

The prefix used for an in-memory file system.

See Also:

Constant Field Values

PREFIX_LZF

public static final java.lang.String PREFIX_LZF

The prefix used for a compressed in-memory file system.

See Also:

Constant Field Values

Method Detail

getInstance

public static FileSystemMemory getInstance()

length

public long length(java.lang.String fileName)

Description copied from class: FileSystem

Get the length of a file.

Specified by:

length in class FileSystem

Parameters:

fileName - the file name

Returns:

the length in bytes

rename

public void rename(java.lang.String oldName,
                   java.lang.String newName)

Description copied from class: FileSystem

Rename a file if this is allowed.

Specified by:

rename in class FileSystem

Parameters:

oldName - the old fully qualified file name

newName - the new fully qualified file name

createNewFile

public boolean createNewFile(java.lang.String fileName)

Description copied from class: FileSystem

Create a new file.

Specified by:

createNewFile in class FileSystem

Parameters:

fileName - the file name

Returns:

true if creating was successful

exists

public boolean exists(java.lang.String fileName)

Description copied from class: FileSystem

Checks if a file exists.

Specified by:

exists in class FileSystem

Parameters:

fileName - the file name

Returns:

true if it exists

delete

public void delete(java.lang.String fileName)

Description copied from class: FileSystem

Delete a file.

Specified by:

delete in class FileSystem

Parameters:

fileName - the file name

tryDelete

public boolean tryDelete(java.lang.String fileName)

Description copied from class: FileSystem

Try to delete a file.

Specified by:

tryDelete in class FileSystem

Parameters:

fileName - the file name

Returns:

true if it could be deleted

listFiles

public java.lang.String[] listFiles(java.lang.String path)

Description copied from class: FileSystem

List the files in the given directory.

Specified by:

listFiles in class FileSystem

Parameters:

path - the directory

Returns:

the list of fully qualified file names

deleteRecursive

public void deleteRecursive(java.lang.String fileName,
                            boolean tryOnly)

Description copied from class: FileSystem

Delete a directory or file and all subdirectories and files.

Specified by:

deleteRecursive in class FileSystem

Parameters:

fileName - the directory

tryOnly - whether errors should be ignored

isReadOnly

public boolean isReadOnly(java.lang.String fileName)

Description copied from class: FileSystem

Check if a file is read-only.

Specified by:

isReadOnly in class FileSystem

Parameters:

fileName - the file name

Returns:

if it is read only

setReadOnly

public boolean setReadOnly(java.lang.String fileName)

Description copied from class: FileSystem

Disable the ability to write.

Specified by:

setReadOnly in class FileSystem

Parameters:

fileName - the file name

Returns:

true if the call was successful

getCanonicalPath

public java.lang.String getCanonicalPath(java.lang.String fileName)

Description copied from class: FileSystem

Normalize a file name.

Specified by:

getCanonicalPath in class FileSystem

Parameters:

fileName - the file name

Returns:

the normalized file name

getParent

public java.lang.String getParent(java.lang.String fileName)

Description copied from class: FileSystem

Get the parent directory of a file or directory.

Specified by:

getParent in class FileSystem

Parameters:

fileName - the file or directory name

Returns:

the parent directory name

isDirectory

public boolean isDirectory(java.lang.String fileName)

Description copied from class: FileSystem

Check if it is a file or a directory.

Specified by:

isDirectory in class FileSystem

Parameters:

fileName - the file or directory name

Returns:

true if it is a directory

isAbsolute

public boolean isAbsolute(java.lang.String fileName)

Description copied from class: FileSystem

Check if the file name includes a path.

Specified by:

isAbsolute in class FileSystem

Parameters:

fileName - the file name

Returns:

if the file name is absolute

getLastModified

public long getLastModified(java.lang.String fileName)

Description copied from class: FileSystem

Get the last modified date of a file

Specified by:

getLastModified in class FileSystem

Parameters:

fileName - the file name

Returns:

the last modified date

canWrite

public boolean canWrite(java.lang.String fileName)

Description copied from class: FileSystem

Check if the file is writable.

Specified by:

canWrite in class FileSystem

Parameters:

fileName - the file name

Returns:

if the file is writable

copy

public void copy(java.lang.String source,
                 java.lang.String target)

Description copied from class: FileSystem

Copy a file from one directory to another, or to another file.

Specified by:

copy in class FileSystem

Parameters:

source - the name of the original file

target - the file name of the copy

createDirs

public void createDirs(java.lang.String fileName)

Description copied from class: FileSystem

Create all required directories that are required for this file.

Specified by:

createDirs in class FileSystem

Parameters:

fileName - the file name (not directory name)

getFileName

public java.lang.String getFileName(java.lang.String name)

Description copied from class: FileSystem

Get the file name (without directory part).

Specified by:

getFileName in class FileSystem

Parameters:

name - the directory and file name

Returns:

just the file name

fileStartsWith

public boolean fileStartsWith(java.lang.String fileName,
                              java.lang.String prefix)

Description copied from class: FileSystem

Check if a file starts with a given prefix.

Specified by:

fileStartsWith in class FileSystem

Parameters:

fileName - the complete file name

prefix - the prefix

Returns:

true if it starts with the prefix

openFileOutputStream

public java.io.OutputStream openFileOutputStream(java.lang.String fileName,
                                                 boolean append)

Description copied from class: FileSystem

Create an output stream to write into the file.

Specified by:

openFileOutputStream in class FileSystem

Parameters:

fileName - the file name

append - if true, the file will grow, if false, the file will be truncated first

Returns:

the output stream

openFileInputStream

public java.io.InputStream openFileInputStream(java.lang.String fileName)

Description copied from class: FileSystem

Create an input stream to read from the file.

Specified by:

openFileInputStream in class FileSystem

Parameters:

fileName - the file name

Returns:

the input stream

openFileObject

public FileObject openFileObject(java.lang.String fileName,
                                 java.lang.String mode)

Description copied from class: FileSystem

Open a random access file object.

Specified by:

openFileObject in class FileSystem

Parameters:

fileName - the file name

mode - the access mode. Supported are r, rw, rws, rwd

Returns:

the file object

accepts

protected boolean accepts(java.lang.String fileName)

Description copied from class: FileSystem

Check if the file system is responsible for this file name.

Specified by:

accepts in class FileSystem

Parameters:

fileName - the file name

Returns:

true if it is

unwrap

public java.lang.String unwrap(java.lang.String fileName)

Description copied from class: FileSystem

Get the unwrapped file name (without wrapper prefixes if wrapping / delegating file systems are used).

Specified by:

unwrap in class FileSystem

Parameters:

fileName - the file name

Returns:

the unwrapped