jsimple.io

Class File

java.lang.Object

jsimple.io.Path

jsimple.io.File

Direct Known Subclasses:

FileSystemFile

public abstract class File
extends Path

Since:

11/22/12 12:14 AM

Constructor Summary

Constructors

Constructor and Description
File()

Method Summary

Modifier and Type	Method and Description
void	copyTo(OutputStream outputStream) Copy the contents of this file to the specified output stream.
abstract void	delete() Delete this file if it exists.
abstract boolean	exists() See if the file exists.
abstract long	getLastModifiedTime() Get the last modified / last write timestamp of this file.
abstract Directory	getParent()
abstract long	getSize() Get the size of this file.
abstract void	moveTo(File destination)
abstract OutputStream	openForCreate() Open the file for writing.
OutputStream	openForCreateAtomic()
OutputStream	openForCreateAtomic(long lastModifiedTime) Open the file for writing/creating, replacing the current file if it already exists.
abstract InputStream	openForRead()
Utf8OutputStreamWriter	openUtf8ForCreate() This is a convenience method to open a UTF8 text file for writing.
Utf8OutputStreamWriter	openUtf8ForCreateAtomic() This is a convenience method to open a UTF8 text file for writing.
Utf8InputStreamReader	openUtf8ForRead() This is a convenience method to open a UTF8 text file for read.
abstract void	renameTo(java.lang.String newName) Rename this file, giving it a new name in the same directory.
abstract void	setLastModifiedTime(long time) Set the last modified / last write timestamp of this file.

Methods inherited from class jsimple.io.Path

getName, getNameExtension, getPathString, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

File

public File()

Method Detail

openForRead

public abstract InputStream openForRead()

copyTo

public void copyTo(OutputStream outputStream)

Copy the contents of this file to the specified output stream. If an error occurs when copying, the file input stream is closed (as you'd expect), an exception is thrown, and the output stream may be partially written to.

Parameters:

outputStream - output stream to write to

openUtf8ForRead

public Utf8InputStreamReader openUtf8ForRead()

This is a convenience method to open a UTF8 text file for read. It does the same thing as calling new Utf8InputStreamReader(openForRead()).

Returns:

Utf8InputStreamReader for reading from this text file

openForCreate

public abstract OutputStream openForCreate()

Open the file for writing. If the file already exists, it is truncated. If the file doesn't exist, it is created. Note that the current JSimple file I/O model is that files, when written, are completely rewritten.

Returns:

output stream, to write the file contents

openUtf8ForCreate

public Utf8OutputStreamWriter openUtf8ForCreate()

This is a convenience method to open a UTF8 text file for writing. It does the same thing as calling new Utf8OutputStreamWriter(openForWrite()).

Returns:

Utf8OutputStreamWriter for writing to this text file

openUtf8ForCreateAtomic

public Utf8OutputStreamWriter openUtf8ForCreateAtomic()

This is a convenience method to open a UTF8 text file for writing. It does the same thing as calling new Utf8OutputStreamWriter(openForCreateAtomic()).

Returns:

Utf8OutputStreamWriter for writing to this text file

openForCreateAtomic

public OutputStream openForCreateAtomic()

openForCreateAtomic

public OutputStream openForCreateAtomic(long lastModifiedTime)

Open the file for writing/creating, replacing the current file if it already exists.

All writes are first made to a temp file (filename + "-temp" suffix, in the same directory). When the returned stream is closed, the new file is committed by renaming the -temp file to the original. That way, the file is either completely updated or not updated at all, never left in a half-updated state.

If lastModifiedTime is non-zero, then it's set as the last modified time on the file, as part of the atomic update (the timestamp is set on the temp file first & preserved on the rename).

Parameters:

lastModifiedTime - modification time in millis, set on updated file; ignored if zero

Returns:

OutputStream, with a close handler attached to update the original file when closed

delete

public abstract void delete()

Delete this file if it exists. If the file doesn't exist, no exception is thrown.

exists

public abstract boolean exists()

See if the file exists. If there's an error checking if the file exists, this method throws an exception when possible, though for some platform implementations it'll just return false if platform can't distinguish not existing from there being an error checking.

Returns:

true if the file exists

renameTo

public abstract void renameTo(java.lang.String newName)

Rename this file, giving it a new name in the same directory. If a file with the specified name already exists, it's replaced. If/when there's the need to move a File to a different directory, we'll add separate support for that.

Parameters:

newName -

moveTo

public abstract void moveTo(File destination)

getLastModifiedTime

public abstract long getLastModifiedTime()

Get the last modified / last write timestamp of this file. Of the 3 file timestamps (created, modified, and accessed) on files, modified is most important in Windows. It's the one displayed by default with the "dir" command and shown in file details in Explorer. It's also the timestamp used for most other applications. So that's the timestamp that JSimple best supports querying and changing.

Returns:

last modified timestamp for file

getSize

public abstract long getSize()

Get the size of this file.

Returns:

file size

setLastModifiedTime

public abstract void setLastModifiedTime(long time)

Set the last modified / last write timestamp of this file. Of the 3 file timestamps (created, modified, and accessed) on files, modified is most important in Windows. It's the one displayed by default with the "dir" command and shown in file details in Explorer. It's also the timestamp used for most other applications. So that's the timestamp that JSimple best supports querying and changing.

Parameters:

time - time in millis (milliseconds since Jan 1, 1970 UTC)

getParent

public abstract Directory getParent()