javax.microedition.io.file
Interface FileConnection

All Superinterfaces:

Connection, InputConnection, OutputConnection, StreamConnection

All Known Subinterfaces:

ExtendedFileConnection

public interface FileConnection
extends StreamConnection

This interface is intended to access files or directories that are located on removeable media and/or file systems on a device.

The internal file systems that are in memory on a device can also be accessed through this class, provided there is underlying hardware and operating system support. If file connections are not supported for a particular media or file system, attempts to open a file connection to the media or file system through Connector.open() results in the javax.microedition.io.IOException being thrown.

Establishing a Connection

The format of the input string used to access a FileConnection through Connector.open() must follow the format of a fully-qualified, absolute path file name as described by the file URL format in IETF RFCs 1738 and 2396. Further detail for the File URL format can be found in the javax.microedition.io.file package description.

A single connection object only references one file or directory at a time. In some cases a connection object can be reused to refer to a different file or directory from the one it was originally associated with (see FileConnection.setFileConnection(java.lang.String)). In general, the best approach to reference a different file or directory is by establishing a completely separate connection through the Connector.open() method.

FileConnection Behavior

FileConnection is different from other Generic Connection Framework connections in that a connection object can be successfully returned from the Connector.open() method without actually referencing an existing entity (in this case, a file or directory). This behavior allows the creation of new files and directories on a file system. For example, the following code can be used to create a new file on a file system, where CFCard is a valid existing file system root name for a given implementation:

 try {
     FileConnection fconn = (FileConnection)Connector.open("file:///CFCard/newfile.txt");
     // If no exception is thrown, then the URI is valid, but the file may or may not exist.
     if (!fconn.exists())
         fconn.create();  // create the file if it doesn't exist

     fconn.close();
 }
 catch (IOException ioe) {
 }

You should always check for the existence of a file or directory after a connection is established to determine if the file or directory actually exists. Similarly, files or directories can be deleted using the FileConnection.delete() method, and you should close the connection immediately after deletion to prevent a connection from trying to access a nonexistent file or directory.

A file connection's open status is unaffected by the opening and closing of input and output streams from the file connection; the file connection stays open until close() is invoked on the FileConnection instance. Input and output streams can be opened and closed multiple times on a FileConnection instance.

All FileConnection instances have one underlying InputStream and one OutputStream. Opening a DataInputStream counts as opening an InputStream, and opening a DataOutputStream counts as opening an OutputStream. A FileConnection instance can have only one InputStream and one OutputStream open at any one time. Trying to open more than one InputStream or more than one OutputStream from a StreamConnection causes an IOException. Trying to open an InputStream or an OutputStream after the FileConnection has been closed causes an IOException.

The inherited StreamConnection methods in a FileConnection instance are not synchronized. The only stream method that can be called safely from another thread is close. When close is invoked on a stream that is executing in another thread, any pending I/O method must throw an InterruptedIOException. In the above case, implementations should try to throw the exception in a timely manner. When all open streams are closed and the FileConnection is closed, any pending I/O operations must be interrupted in a timely manner.

Data written to the output streams of these FileConnection objects is not guaranteed to be flushed to the stream's destination (and subsequently made available to any input streams) until either flush() or close() is invoked on the stream.

Security

Access to file connections is restricted to prevent unauthorized manipulation of data. The access security model applied to the file connection is defined by the implementing profile. The security model is applied on the invocation of the Connector.open() method with a valid file connection string. The mode provided in the open() method (Connector.READ_WRITE by default) indicates the application's request for access rights for the indicated file or directory and is therefore checked against the security scheme. All three connections modes (READ_WRITE, WRITE, and READ) are supported for a file connection and determine the access requested from the security model.

The security model is also applied during use of the returned FileConnection, specifically when the methods openInputStream(), openDataInputStream(), openOutputStream(), and openDataOutputStream() are invoked. These methods have an implied request for access rights (input stream access requests read access, and output stream access requests write access). If the application is not granted the appropriate read or write access to the file or file system by the profile authorization scheme, the RuntimeException java.lang.SecurityException is thrown.

File access through the File Connection API may be restricted to files that are within a public context and not deemed private or sensitive. This restriction is intended to protect the device's and other users' files and data from both malicious and unintentional access. RMS databases cannot be accessed using the File Connection API. Access to files and directories that are private to another application, files and directories that are private to a different user than the current user, system configuration files, and device and OS specific files and directories may be restricted. In these situations, a RuntimeException java.lang.SecurityException is thrown from the Connector.open() method if the file, file system, or directory cannot be accessed.

See Also:

FileSystemRegistry

Since:

BlackBerry API 4.2.0, FileConnection 1.0

Method Summary
long	availableSize() Determines the free memory that is available on the file system that the file or directory resides on.
boolean	canRead() Checks if the file or directory is readable.
boolean	canWrite() Checks if the file or directory is writable.
void	create() Creates a file corresponding to the file string provided in the Connector.open() method for this FileConnection.
void	delete() Deletes the file or directory specified in the Connector.open() URL.
long	directorySize(boolean includeSubDirs) Determines the size in bytes on a file system of all of the files that are contained in a directory.
boolean	exists() Checks if the file or directory specified in the URL passed to the Connector.open() method exists.
long	fileSize() Determines the size of a file on the file system.
String	getName() Returns the name of a file or directory excluding the URL schema and all paths.
String	getPath() Returns the path, excluding the file or directory name and the "file" URL schema and host from where the file or directory specified in the Connector.open() method is opened.
String	getURL() Returns the full file URL including the scheme, host, and path from where the file or directory specified in the Connector.open() method is opened.
boolean	isDirectory() Checks if the URL passed to the Connector.open() is a directory.
boolean	isHidden() Checks if the file is hidden.
boolean	isOpen() Returns whether the file connection is currently open or not.
long	lastModified() Returns the time that the file denoted by the URL specified in the Connector.open() method was last modified.
Enumeration	list() Gets a list of all files and directories contained in a directory.
Enumeration	list(String filter, boolean includeHidden) Gets a filtered list of files and directories contained in a directory.
void	mkdir() Creates a directory corresponding to the directory string provided in the Connector.open() method.
DataInputStream	openDataInputStream() Opens and returns a data input stream for a connection.
DataOutputStream	openDataOutputStream() Opens and returns a data output stream for a connection.
InputStream	openInputStream() Opens and returns an input stream for a connection.
OutputStream	openOutputStream() Opens and returns an output stream for a connection.
OutputStream	openOutputStream(long byteOffset) Opens an output stream and positions it at the indicated byte offset in the file.
void	rename(String newName) Renames the selected file or directory to a new name in the same directory.
void	setFileConnection(String fileName) Resets this FileConnection object to another file or directory.
void	setHidden(boolean hidden) Sets the hidden attribute of the selected file to the value provided.
void	setReadable(boolean readable) Sets the file or directory readable attribute to the indicated value.
void	setWritable(boolean writable) Sets the selected file or directory writable attribute to the indicated value.
long	totalSize() Determines the total size of the file system the connection's target resides on.
void	truncate(long byteOffset) Truncates the file, discarding all data from the given byte offset to the current end of the file.
long	usedSize() Determines the used memory of the file system where the connection's target resides.

Methods inherited from interface javax.microedition.io.Connection

close

Methods inherited from interface javax.microedition.io.Connection

close

Method Detail

isOpen

boolean isOpen()

Returns whether the file connection is currently open or not.

Returns:

true if the file connection is open; otherwise false.

Since:

BlackBerry API 4.2.0

openInputStream

InputStream openInputStream()
                            throws IOException

Opens and returns an input stream for a connection. For the input stream to be created, the target of the connection must already exist and be accessible.

Specified by:

openInputStream in interface InputConnection

Returns:

An open input stream.

Throws:

IOException - If an I/O error occurs, if the method is invoked on a directory, if the connection's target does not yet exist, or if the connection's target is not accessible.

IllegalModeException - If the application does have read access to the connection's target but has opened the connection in Connector.WRITE mode.

SecurityException - If the application is not granted read access to the connection's target.

Since:

BlackBerry API 4.2.0

openDataInputStream

DataInputStream openDataInputStream()
                                    throws IOException

Opens and returns a data input stream for a connection. For the input stream to be created, the target of the connection must already exist and be accessible.

Specified by:

openDataInputStream in interface InputConnection

Returns:

An open input stream

Throws:

IOException - If an I/O error occurs, if the method is invoked on a directory, if the connection's target does not yet exist, or if the connection's target is not accessible.

IllegalModeException - If the application has read access to the connection's target but has opened the connection in Connector.WRITE mode.

SecurityException - If the application is not granted read access to the connection's target.

Since:

BlackBerry API 4.2.0

openOutputStream

OutputStream openOutputStream()
                              throws IOException

Opens and returns an output stream for a connection. The output stream is positioned at the start of the file. Writing data to the output stream overwrites the contents of the files. Writing data to output streams beyond the current end of the file automatically extends the file size. For the output stream to be created, the connection's target must already exist and be accessible. FileConnection.openOutputStream(long) should be used to position an output stream at a different position in the file.

Changes made to a file through an output stream may not be immediately made to the actual file residing on the file system because platform and implementation specific use of caching and buffering of the data. Steam contents and file length extensions may not be immediately visible outside of the application unless flush() is called on the stream. The returned output stream is automatically and synchronously flushed when it is closed.

Specified by:

openOutputStream in interface OutputConnection

Returns:

An open output stream

Throws:

IOException - If an I/O error occurs, if the method is invoked on a directory, if the connection's target does not yet exist, or if the connection's target is not accessible.

IllegalModeException - If the application does have write access to the connection's target but has opened the connection in Connector.READ mode.

SecurityException - If the application is not granted write access to the connection's target.

See Also:

FileConnection.openOutputStream(long)

Since:

BlackBerry API 4.2.0

openDataOutputStream

DataOutputStream openDataOutputStream()
                                      throws IOException

Opens and returns a data output stream for a connection. The output stream is positioned at the start of the file. Writing data to the output stream overwrites the contents of the files. Writing data to output streams beyond the current end of the file automatically extends the file size. For the output stream to be created, the connection's target must already exist and be accessible. FileConnection.openOutputStream(long) should be used to position an output stream at a different position in the file.

Changes made to a file through an output stream may not be immediately made to the actual file residing on the file system because platform and implementation specific use of caching and buffering of the data. Steam contents and file length extensions may not be immediately visible outside of the application unless flush() is called on the stream. The returned output stream is automatically and synchronously flushed when it is closed.

Specified by:

openDataOutputStream in interface OutputConnection

Returns:

An open output stream.

Throws:

IOException - If an I/O error occurs, if the method is invoked on a directory, if the connection's target does not yet exist, or if the connection's target is not accessible.

IllegalModeException - If the application does have write access to the connection's target but has opened the connection in Connector.READ mode.

SecurityException - If the application is not granted write access to the connection's target.

See Also:

FileConnection.openOutputStream(long)

Since:

BlackBerry API 4.2.0

openOutputStream

OutputStream openOutputStream(long byteOffset)
                              throws IOException

Opens an output stream and positions it at the indicated byte offset in the file. Data written to the returned output stream at that position overwrites any existing data until EOF is reached, and then additional data is appended. The connection's target must already exist and be accessible for the output stream to be created.

Changes made to a file through an output stream may not be immediately made to the actual file residing on the file system because platform and implementation specific use of caching and buffering of the data. Steam contents and file length extensions are not necessarily visible outside of the application immediately unless flush() is called on the stream. The returned output stream is automatically and synchronously flushed when it is closed.

Parameters:

byteOffset - Number of bytes to skip over from the beginning of the file when positioning the start of the OutputStream. If the provided offset is larger than or equal to the current file size, the OutputStream is positioned at the current end of the file for appending.

Returns:

An open OutputStream positioned at the byte offset in the file, or at the end of the file if the offset is greater than the size of the file.

Throws:

IOException - If an I/O error occurs, if the method is invoked on a directory, if the connection's target does not yet exist, or if the connection's target is not accessible.

IllegalModeException - If the application does have write access to the connection's target but has opened the connection in Connector.READ mode.

SecurityException - If the security if the application does not allow write access to the file.

IllegalArgumentException - If byteOffset has a negative value.

Since:

BlackBerry API 4.2.0

totalSize

long totalSize()

Determines the total size of the file system the connection's target resides on.

Returns:

The total size of the file system in bytes, or -1 if the file system is not accessible.

Throws:

SecurityException - If the security of the application does not have read access to the root volume.

IllegalModeException - If the application does have read access to the connection's target but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

availableSize

long availableSize()

Determines the free memory that is available on the file system that the file or directory resides on. This may only be an estimate and may vary based on platform-specific file system blocking and metadata information.

Returns:

The available size in bytes on a file system, or -1 if the file system is not accessible.

Throws:

SecurityException - If the security of the application does not have read access to the root volume.

IllegalModeException - If the application does have read access to the directory but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

usedSize

long usedSize()

Determines the used memory of the file system where the connection's target resides. This may only be an estimate and may vary based on platform-specific file system blocking and metadata information.

Returns:

The used number of bytes on a file system, or -1 if the file system is not accessible.

Throws:

SecurityException - If the security of the application does not have read access to the root volume.

IllegalModeException - If the application has read access to the directory but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

directorySize

long directorySize(boolean includeSubDirs)
                   throws IOException

Determines the size in bytes on a file system of all of the files that are contained in a directory.

Parameters:

includeSubdirs - If set to true, the method determines the size of the given directory and all subdirectories recursively. If false, the method returns the size of the files in the directory only.

Returns:

The size in bytes occupied by the files included in the directory, or -1 if the directory does not exist or is not accessible.

Throws:

IOException - If the method is invoked on a file.

SecurityException - If the security of the application does not have read access for the directory.

IllegalModeException - If the application has read access to the directory but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

fileSize

long fileSize()
              throws IOException

Determines the size of a file on the file system. The size of a file always represents the number of bytes contained in the file; there is no pre-allocated but empty space in a file.

fileSize() always returns size of the file on the file system, and not in any pending output stream. flush() should be used before calling fileSize() to ensure the contents of the output streams opened to the file get written to the file system.

Returns:

The size in bytes of the selected file, or -1 if the file does not exist or is not accessible.

Throws:

IOException - If the method is invoked on a directory.

SecurityException - If the security of the application does not have read access for the file.

IllegalModeException - If the application has read access to the file but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

canRead

boolean canRead()

Checks if the file or directory is readable. This method checks the attributes associated with a file or directory by the underlying file system. Some file systems may not support associating attributes with a file, in which case this method returns true.

Returns:

true if the connection's target exists, is accessible, and is readable; otherwise false.

Throws:

SecurityException - If the security of the application does not have read access for the connection's target.

IllegalModeException - If the application has read access to the connection's target but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

See Also:

FileConnection.setReadable(boolean)

Since:

BlackBerry API 4.2.0

canWrite

boolean canWrite()

Checks if the file or directory is writable. This method checks the attributes associated with a file or directory by the underlying file system. Some file systems may not support associating attributes with a file, in which case this method returns true.

Returns:

true if the connection's target exists, is accessible, and is writable; otherwise false.

Throws:

SecurityException - If the security of the application does not have read access for the connection's target.

IllegalModeException - If the application has read access to the connection's target but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

See Also:

FileConnection.setWritable(boolean)

Since:

BlackBerry API 4.2.0

isHidden

boolean isHidden()

Checks if the file is hidden. The exact definition of hidden is system-dependent. For example, on UNIX systems a file is considered to be hidden if its name begins with a period character ('.'). On Win32 and FAT file systems, a file is considered to be hidden if it has been marked as such in the file's attributes. If hidden files are not supported on the referenced file system, this method always returns false.

Returns:

true if the file exists, is accessible, and is hidden, otherwise false.

Throws:

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have read access for the connection's target.

IllegalModeException - If the application has read access to the connection's target but has opened the connection in Connector.WRITE mode.

See Also:

FileConnection.setHidden(boolean)

Since:

BlackBerry API 4.2.0

setReadable

void setReadable(boolean readable)
                 throws IOException

Sets the file or directory readable attribute to the indicated value. The readable attribute for the file on the actual file system is set immediately upon invocation of this method. If the file system doesn't support a settable read attribute, this method is ignored and canRead() always returns true.

Parameters:

readable - The new state of the readable flag of the selected file.

Throws:

IOException - If the connection's target does not exist or is not accessible.

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have write access to the connection's target.

IllegalModeException - If the application has write access to the connection's target but has opened the connection in Connector.READ mode.

See Also:

FileConnection.canRead()

Since:

BlackBerry API 4.2.0

setWritable

void setWritable(boolean writable)
                 throws IOException

Sets the selected file or directory writable attribute to the indicated value. The writable attribute for the file on the actual file system is set immediately upon invocation of the method. If the file system doesn't support a settable write attribute, this method is ignored and canWrite() always returns true.

Parameters:

writable - The new state of the writable flag of the selected file.

Throws:

IOException - If the connection's target does not exist or is not accessible.

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have write access to the connection's target.

IllegalModeException - If the application has write access to the connection's target but has opened the connection in Connector.READ mode.

See Also:

FileConnection.canWrite()

Since:

BlackBerry API 4.2.0

setHidden

void setHidden(boolean hidden)
               throws IOException

Sets the hidden attribute of the selected file to the value provided. The attribute is applied to the file on the actual file system immediately upon invocation of this method if the file system and platform support it. If the file system doesn't support a hidden attribute, this method is ignored and isHidden() always returns false. Since the exact definition of hidden is system-dependent, this method only works on file systems that support a settable file attribute. For example, on Win32 and FAT file systems, a file may be considered hidden if it has been marked as such in the file's attributes; therefore this method is applicable. However on UNIX systems a file may be considered to be hidden if its name begins with a period character (.). In the UNIX case, this method can be ignored; to make a file hidden, use the rename() method.

Parameters:

hidden - The new state of the hidden flag of the selected file.

Throws:

IOException - If the connection's target does not exist or is not accessible.

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have write access to the connection's target.

IllegalModeException - If the application has write access to the connection's target but has opened the connection in Connector.READ mode.

See Also:

FileConnection.isHidden()

Since:

BlackBerry API 4.2.0

list

Enumeration list()
                 throws IOException

Gets a list of all files and directories contained in a directory. The directory is the connection's target as specified in Connector.open().

Returns:

An Enumeration of strings, denoting the files and directories in the directory. The string returned contains only the file or directory name and does not contain any path prefix. (To get a complete path for each file or directory, prepend FileConnection.getPath().) Directories are denoted with a trailing slash (/) in their returned name. The Enumeration has zero length if the directory is empty. Any hidden files and directories in the directory are not included in the returned list. Any current or parent directory indication ("." or "..") is not included in the list of files and directories that is returned.

Throws:

IOException - If invoked on a file and the directory does not exist, the directory is not accessible, or an I/O error occurs.

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have read access for the directory.

IllegalModeException - If the application has read access to the directory but has opened the connection in Connector.WRITE mode.

Since:

BlackBerry API 4.2.0

list

Enumeration list(String filter,
                 boolean includeHidden)
                 throws IOException

Gets a filtered list of files and directories contained in a directory. The directory is the connection's target as specified in Connector.open().

Parameters:

filter - String against which all files and directories are matched for retrieval. An asterisk (*) can be used as a wildcard to represent zero or more occurrences of any character.

includeHidden - Boolean indicating whether files that are marked as hidden should be included or not in the list of files and directories that is returned.

Returns:

An Enumeration of strings, denoting the files and directories in the directory that match the filter. Directories are denoted with a trailing slash (/) in their returned name. The Enumeration has zero length if the directory is empty or if no files or directories are found matching the given filter. Any current or parent directory indication ("." or "..") is not included in the list of files and directories that is returned.

Throws:

IOException - If invoked on a file, the directory does not exist, the directory is not accessible, or an I/O error occurs.

ConnectionClosedException - If the connection is closed.

SecurityException - if the security of the application does not have read access for the directory.

IllegalModeException - If the application does have read access to the connection's target but has opened the connection in Connector.WRITE mode.

NullPointerException - If filter is null.

IllegalArgumentException - If a filter contains any path specification or is an invalid filename for the platform.

Since:

BlackBerry API 4.2.0

create

void create()
            throws IOException

Creates a file corresponding to the file string provided in the Connector.open() method for this FileConnection. The Upon invocation of this method, the file is created immediately on the actual file system. Files are created with zero length and data can be put into the file through output streams opened on the file. This method does not create any directories specified in the file's path.

Throws:

SecurityException - If the security of the application does not have write access for the file.

IllegalModeException - If the application does have write access to the file but has opened the connection in Connector.READ mode.

IOException - If invoked on an existing file or on any directory (mkdir() is used to create directories), the connection's target has a trailing slash (/) to denote a directory, the target file system is not accessible, or an unspecified error occurs preventing creation of the file.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

mkdir

void mkdir()
           throws IOException

Creates a directory corresponding to the directory string provided in the Connector.open() method. Upon invocation of this method, the directory is created immediately on the actual file system. Directories in the specified path are not recursively created and must be explicitly created before subdirectories can be created.

Throws:

SecurityException - If the security of the application does not have write access to the directory.

IllegalModeException - If the application does have write access to the directory but has opened the connection in Connector.READ mode.

IOException - If invoked on an existing directory or on any file (create() is used to create files), the target file sytem is not accessible, or an unspecified error occurs preventing creation of the directory.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

exists

boolean exists()

Checks if the file or directory specified in the URL passed to the Connector.open() method exists.

Returns:

true if the connnection's target exists and is accessible, otherwise false.

Throws:

SecurityException - If the security of the application does not have read access for the connection's target.

IllegalModeException - If the application has read access to the connection's target but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0

isDirectory

boolean isDirectory()

Checks if the URL passed to the Connector.open() is a directory.

Returns:

true if the connection's target exists, is accessible, and is a directory; otherwise false.

Throws:

SecurityException - If the security of the application does not have read access for the connection's target.

ConnectionClosedException - If the connection is closed.

IllegalModeException - If the application has read access to the connection's target but has opened the connection in Connector.WRITE mode.

Since:

BlackBerry API 4.2.0

delete

void delete()
            throws IOException

Deletes the file or directory specified in the Connector.open() URL. Upon invocation of this method, the file or directory is deleted immediately on the actual file system. All open input and output streams are automatically flushed and closed. Attempts to further use those streams result in an IOException. The FileConnection instance object remains open and available for use.

Throws:

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have write access to the connection's target.

IllegalModeException - If the application does have write access to the connection's target but has opened the connection in Connector.READ mode.

IOException - If the target is a directory and it is not empty, the connection target does not exist or is unaccessible, or an unspecified error occurs preventing deletion of the target.

Since:

BlackBerry API 4.2.0

rename

void rename(String newName)
            throws IOException

Renames the selected file or directory to a new name in the same directory. Upon invocation of this method, the file or directory is renamed immediately on the actual file system. No file or directory by the original name exists after this method call. All previously open input and output streams are automatically flushed and closed. Attempts to further use those streams result in an IOException. The FileConnection instance object remains open and available for use, referring now to the file or directory by its new name.

Parameters:

newName - The new name of the file or directory. The name must not contain any path specification; the file or directory remains in its same directory as before this method call.

Throws:

IOException - If the connection's target does not exist, the connection's target is not accessible, a file or directory already exists by the newName, or newName is an invalid filename for the platform.

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have write access to the connection's target.

IllegalModeException - If the application has write access to the connection's target but has opened the connection in Connector.READ mode.

NullPointerException - If newName is null.

IllegalArgumentException - If newName contains any path specification.

Since:

BlackBerry API 4.2.0

truncate

void truncate(long byteOffset)
              throws IOException

Truncates the file, discarding all data from the given byte offset to the current end of the file. If the byte offset that is provided is greater than or equal to the file's current byte count, this method returns without changing the file. Any open streams are flushed automatically before the truncation occurs.

Parameters:

byteOffset - The offset into the file from which truncation occurs.

Throws:

IOException - If invoked on a directory or the file does not exist or is not accessible.

ConnectionClosedException - If the connection is closed.

SecurityException - If the security of the application does not have write access to the file.

IllegalModeException - If the application does have write access to the file but has opened the connection in Connector.READ mode.

IllegalArgumentException - If byteOffset is less than zero.

Since:

BlackBerry API 4.2.0

setFileConnection

void setFileConnection(String fileName)
                       throws IOException

Resets this FileConnection object to another file or directory. This allows reuse of the FileConnection object for directory traversal. The current FileConnection object must refer to a directory, and the new file or directory must exist within this directory. The string ".." can be used to indicate the parent directory for the current connection. The FileConnection instance remains open and available for use, referring now to the newly specified file or directory.

Parameters:

fileName - The name of the file or directory to which this FileConnection is reset. The fileName must be one of the values returned from the FileConnection.list() method, or the string ".." to indicate the parent directory of the current connection. The fileName must not contain any additional path specification; i.e. the file or directory must reside within the current directory.

Throws:

NullPointerException - If fileName is null.

SecurityException - If the security of the application does not have the security access to the specified file or directory as requested in the Connector.open method invocation that originally opened this FileConnection.

IllegalArgumentException - If fileName contains any path specification or does not yet exist.

IOException - If the current FileConnection is opened on a file, the connection's target is not accessible, or fileName is an invalid filename for the platform (e.g. contains characters invalid in a filename on the platform), or the current connection is connected to the file system's root and the fileName parameter is "..".

ConnectionClosedException - if the connection is closed.

Since:

BlackBerry API 4.2.0

getName

String getName()

Returns the name of a file or directory excluding the URL schema and all paths. Directories are denoted with a trailing slash (/) in their returned name. TheString resulting from this method looks as follows:

   <directory>/
 

or

   <filename.extension>
 

or if no file extension

   <filename>
 

Returns:

The name of a file or directory.

Since:

BlackBerry API 4.2.0

getPath

String getPath()

Returns the path, excluding the file or directory name and the "file" URL schema and host from where the file or directory specified in the Connector.open() method is opened. FileConnection.getName() can be appended to this value to get a fully qualified path filename. The String resulting from this method looks as follows:

   /<root>/<directory>/
 

Returns:

The path of a file or directory in the format specified above.

Since:

BlackBerry API 4.2.0

getURL

String getURL()

Returns the full file URL including the scheme, host, and path from where the file or directory specified in the Connector.open() method is opened. The string that is returned is in escaped ASCII format as defined by RFC 2396. The resulting String looks as follows:

   file://<host>/<root>/<directory>/<filename.extension>
 

or

   file://<host>/<root>/<directory>/<directoryname>/
 

Returns:

The URL of a file or directory in the format specified above.

Since:

BlackBerry API 4.2.0

lastModified

long lastModified()

Returns the time that the file denoted by the URL specified in the Connector.open() method was last modified.

Returns:

A long value representing the time the file was last modified, measured in milliseconds since 00:00:00 GMT, January 1, 1970, or 0L if an I/O error occurs. If modification date is not supported by the underlying platform and/or file system, then 0L is also returned. If the connection's target does not exist or is not accessible, 0L is returned.

Throws:

SecurityException - If the security of the application does not have read access for the connection's target.

IllegalModeException - If the application does have read access to the connection's target but has opened the connection in Connector.WRITE mode.

ConnectionClosedException - If the connection is closed.

Since:

BlackBerry API 4.2.0