| com.sun.midp.io.j2me.file.BaseFileHandler
All known Subclasses: com.sun.midp.io.j2me.file.DefaultFileHandler,
| BaseFileHandler | | interface BaseFileHandler (Code) | | Base file handler.
|
| Method Summary | |
| public long | availableSize()
Determines the free memory that is available on the file system the file
or directory resides on. | | public boolean | canRead()
Check if file corresponding to this filehandler exists and has a
read permission. | | public boolean | canWrite()
Check is file corresponding to this filehandler exists and has a
write permission. | | public void | close()
Close file associated with this handler. | | public void | closeForRead()
Closes for reading the file that was open by openForRead method. | | public void | closeForReadWrite()
Closes the file for both reading and writing. | | public void | closeForWrite()
Closes for writing the file that was open by openForWrite method. | | public void | connect(String rootName, String absFile)
Connect file handler to the abstract file target. | | public void | create()
Create file corresponding to this file handler. | | public void | createPrivateDir(String rootName)
Creates dedicated private working directory for the MIDlet suite. | | public void | delete()
Deletes the file or directory associated with this handler.
The file or directory is deleted immediately on
the actual file system upon invocation of this method. | | public long | directorySize(boolean includeSubDirs)
Determines the size in bytes on a file system of all of the files
that are contained in a directory.
Parameters:
includeSubDirs - if true, size calculation willinclude all subdirectories' size. | | public boolean | exists()
Check is file or directory corresponding to this filehandler exists. | | public long | fileSize()
Determines the size of a file on the file system. | | public void | flush()
Forces any buffered output bytes to be written out. | | public String | illegalFileNameChars()
Returns a string that contains all characters forbidden for the use on
the given platform except "/" (forward slash) which is always considered
illegal. | | public boolean | isDirectory()
Check is file corresponding to this filehandler exists and is a
directory. | | public boolean | isHidden()
Check is file corresponding to this filehandler exists and is
hidden. | | public long | lastModified()
Returns the time that the file denoted by this file handler
was last modified. | | public Vector | list(String filter, boolean includeHidden)
Gets a filtered list of files and directories contained in a directory.
The directory is the handler's target as specified in
create().
Parameters:
filter - String against which all files and directories arematched for retrieval. | | public Vector | listRoots()
List filesystem roots available on the device. | | public void | mkdir()
Creates a directory corresponding to the directory
string provided in the connect() method.
The directory is created immediately on the actual
file system upon invocation of this method. | | public void | openForRead()
Open the file for reading, on the underlying file system. | | public void | openForWrite()
Open the file for writing, on the underlying file system. | | public void | positionForWrite(long offset)
Sets the location for the next write operation. | | public int | read(byte b, int off, int len)
Reads up to len bytes of data from the input stream into
an array of bytes, blocks until at least one byte is available.
Parameters:
b - the buffer into which the data is read.
Parameters:
off - the start offset in array bat which the data is written.
Parameters:
len - the maximum number of bytes to read. | | public void | rename(String newName)
Renames the selected file or directory to a new name in the same
directory. | | public void | setHidden(boolean hidden)
Sets the hidden attribute of the file associated with this file handler
to the value provided. | | public void | setReadable(boolean readable)
Sets the file or directory readable attribute to the
indicated value. | | public void | setWritable(boolean writable)
Sets the file or directory associated with this file handler writable
attribute to the
indicated value. | | public long | totalSize()
Determines the total size of the file system the connection's target
resides on. | | public void | truncate(long byteOffset)
Truncates the file, discarding all data from the given byte offset to
the current end of the file. | | public long | usedSize()
Determines the used memory of a file system the connection's target
resides on. | | public int | write(byte b, int off, int len)
Writes len bytes from the specified byte array
starting at offset off to this output stream.
Polling the native code is done here to allow for simple
asynchronous native code to be written. |
| availableSize | | public long availableSize()(Code) | | Determines the free memory that is available on the file system 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.
The available size in bytes on a file system, or -1 if anerror occurs. |
| canRead | | public boolean canRead()(Code) | | Check if file corresponding to this filehandler exists and has a
read permission.
true if file has read permission, otherwise false |
| canWrite | | public boolean canWrite()(Code) | | Check is file corresponding to this filehandler exists and has a
write permission.
true if file has write permission, otherwise false |
| close | | public void close() throws IOException(Code) | | Close file associated with this handler. Open file and all system
resources should be released by this call. Handler object can be
reused by subsequent call to connect().
throws:
IOException - if I/O error occurs |
| closeForRead | | public void closeForRead() throws IOException(Code) | | Closes for reading the file that was open by openForRead method.
If the file is already closed for reading this method does nothing.
throws:
IOException - if file is directory, file does not exists or otherI/O error occurs |
| closeForReadWrite | | public void closeForReadWrite() throws IOException(Code) | | Closes the file for both reading and writing.
If the file is already closed for reading and writing this method does
nothing.
throws:
IOException - if file is directory, file does not exists or otherI/O error occurs |
| closeForWrite | | public void closeForWrite() throws IOException(Code) | | Closes for writing the file that was open by openForWrite method.
If the file is already closed for writing this method does nothing.
throws:
IOException - if file is directory, file does not exists or otherI/O error occurs |
| connect | | public void connect(String rootName, String absFile)(Code) | | Connect file handler to the abstract file target. This operation should
not trigger any access to the native filesystem.
Parameters:
rootName - The name of the root directory.
Parameters:
absFile - Full path to the file to be handled by this handler.
throws:
IllegalArgumentException - if filename contains charactersnot allowed by the file system. This check should not involveany actual access to the filesystem. |
| create | | public void create() throws IOException(Code) | | Create file corresponding to this file handler. The
file is created immediately on the actual file system upon invocation of
this method. Files are created with zero length and data can be put
into the file through write method after opening the file.This method
does not create any directories specified in the file's path.
throws:
IOException - if invoked on the existing file or unexpected erroroccurs. |
| createPrivateDir | | public void createPrivateDir(String rootName) throws IOException(Code) | | Creates dedicated private working directory for the MIDlet suite.
Does nothing if specified root is not private root or the directory
already exists.
Parameters:
rootName - the name of file root |
| delete | | public void delete() throws IOException(Code) | | Deletes the file or directory associated with this handler.
The file or directory is deleted immediately on
the actual file system upon invocation of this method. Previously open
native file should be closed.The
handler instance object remains connected and available for use.
throws:
IOException - If the target is a directory and it is not empty,the connection target does not exist or is unaccessible, oran unspecified error occurs preventing deletion of the target. |
| directorySize | | public long directorySize(boolean includeSubDirs) throws IOException(Code) | | Determines the size in bytes on a file system of all of the files
that are contained in a directory.
Parameters:
includeSubDirs - if true, size calculation willinclude all subdirectories' size. The size in bytes occupied by the files included in thedirectory, or -1 if the directory does not exist or isnot accessible.
throws:
IOException - if some error occures while accessing the directory. |
| exists | | public boolean exists()(Code) | | Check is file or directory corresponding to this filehandler exists.
true if file exists, otherwise false |
| fileSize | | public long fileSize() throws IOException(Code) | | 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. Users should perform an
explicit flush() on any open output streams to the file
prior to invoking this method to ensure accurate results.
The size in bytes of the selected file, or -1 if thefile does not exist or is not accessible.
throws:
IOException - if the method is invoked on a directory. |
| flush | | public void flush() throws IOException(Code) | | Forces any buffered output bytes to be written out.
The general contract of flush is
that calling it is an indication that, if any bytes previously
written that have been buffered by the connection,
should immediately be written to their intended destination.
The flush method of ConnectionBaseAdapter
does nothing.
exception:
IOException - if an I/O error occurs. |
| illegalFileNameChars | | public String illegalFileNameChars()(Code) | | Returns a string that contains all characters forbidden for the use on
the given platform except "/" (forward slash) which is always considered
illegal. If there are no such characters an empty string is returned.
string of characters not allowed in file names |
| isDirectory | | public boolean isDirectory()(Code) | | Check is file corresponding to this filehandler exists and is a
directory.
true if directory exists, otherwise false |
| isHidden | | public boolean isHidden()(Code) | | Check is file corresponding to this filehandler exists and is
hidden.
true if file is hidden, otherwise false |
| lastModified | | public long lastModified()(Code) | | Returns the time that the file denoted by this file handler
was last modified.
time when the file was last modified. |
| list | | public Vector list(String filter, boolean includeHidden) throws IOException(Code) | | Gets a filtered list of files and directories contained in a directory.
The directory is the handler's target as specified in
create().
Parameters:
filter - String against which all files and directories arematched for retrieval. An asterisk ("*") can be used as awildcard to represent 0 or more occurrences of any character.If null no filtering is performed
Parameters:
includeHidden - boolean indicating whether files marked as hiddenshould be included or not in the list of files and directoriesreturned. An Enumeration of strings, denoting the files and directoriesin the directory matching the filter. Directories are denotedwith a trailing slash "/" in their returned name. TheEnumeration has zero length if the directory is empty or nofiles and/or directories are found matching the given filter.Any current directory indication (".") and any parent directoryindication ("..") is not included in the list of files anddirectories returned.
throws:
IOException - if invoked on a file, the directory does not exist,the directory is not accessible, or an I/O error occurs.
throws:
IllegalArgumentException - if filter contains any pathspecification or is an invalid filename for the platform(e.g. contains characters invalid for a filename on theplatform). |
| listRoots | | public Vector listRoots()(Code) | | List filesystem roots available on the device. For the description of
the correct root format see FileConnection documentation.
array of roots |
| mkdir | | public void mkdir() throws IOException(Code) | | Creates a directory corresponding to the directory
string provided in the connect() method.
The directory is created immediately on the actual
file system upon invocation of this method. Directories in the
specified path are not recursively created and must be explicitly
created before subdirectories can be created.
throws:
IOException - if invoked on an existing directory or on any file(create() is used to create files), the targetfile system is not accessible, or an unspecified error occurspreventing creation of the directory. |
| openForRead | | public void openForRead() throws IOException(Code) | | Open the file for reading, on the underlying file system. File name is
passed in the link#connect() method.
throws:
IOException - if file is directory, file does not exists,if file is already open for read or otherI/O error occurs |
| openForWrite | | public void openForWrite() throws IOException(Code) | | Open the file for writing, on the underlying file system. File name is
passed in the link#connect() method.
throws:
IOException - if file is directory, file does not exists,i if file is already open for write or otherI/O error occurs |
| positionForWrite | | public void positionForWrite(long offset) throws IOException(Code) | | Sets the location for the next write operation.
Parameters:
offset - location for next write
throws:
IOException - if an error occurs |
| read | | public int read(byte b, int off, int len) throws IOException(Code) | | Reads up to len bytes of data from the input stream into
an array of bytes, blocks until at least one byte is available.
Parameters:
b - the buffer into which the data is read.
Parameters:
off - the start offset in array bat which the data is written.
Parameters:
len - the maximum number of bytes to read. the total number of bytes read into the buffer, or-1 if there is no more data because the end ofthe stream has been reached.
exception:
IOException - if an I/O error occurs. |
| rename | | public void rename(String newName) throws IOException(Code) | | Renames the selected file or directory to a new name in the same
directory. The file or directory is renamed immediately on the actual
file system upon invocation of this method. No file or directory by the
original name exists after this method call. Previously open native file
should be closed. The handler
instance object remains connected 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 mustbe the full qualified name of the new file
throws:
IOException - if the connection's target does not exist, theconnection's target is not accessible, a file or directoryalready exists by the newName, ornewName is an invalid filename for the platform(e.g. contains characters invalid in a filename onthe platform). |
| setHidden | | public void setHidden(boolean hidden) throws IOException(Code) | | Sets the hidden attribute of the file associated with this file handler
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 may be ignored and
the method to make a file hidden may be 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 notaccessible.
See Also: BaseFileHandler.isHidden |
| setReadable | | public void setReadable(boolean readable) throws IOException(Code) | | 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 theselected file.
throws:
IOException - if the connection's target does not exist or is notaccessible.
See Also: BaseFileHandler.canRead |
| setWritable | | public void setWritable(boolean writable) throws IOException(Code) | | Sets the file or directory associated with this file handler 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 selectedfile.
throws:
IOException - if the connection's target does not exist or is notaccessible.
See Also: BaseFileHandler.canWrite |
| totalSize | | public long totalSize()(Code) | | Determines the total size of the file system the connection's target
resides on.
The total size of the file system in bytes, or -1 if anerror occurs. |
| truncate | | public void truncate(long byteOffset) throws IOException(Code) | | Truncates the file, discarding all data from the given byte offset to
the current end of the file. If the byte offset provided is greater
than or equal to the file's current byte count, the method returns
without changing the file.
Parameters:
byteOffset - the offset into the file from which truncationoccurs.
throws:
IOException - if invoked on a directory or the file does notexist or is not accessible. |
| usedSize | | public long usedSize()(Code) | | Determines the used memory of a file system the connection's target
resides on. This may only be an estimate and may vary based
on platform-specific file system blocking and metadata information.
The used size of bytes on a file system, or -1 if anerror occurs. |
| write | | public int write(byte b, int off, int len) throws IOException(Code) | | Writes len bytes from the specified byte array
starting at offset off to this output stream.
Polling the native code is done here to allow for simple
asynchronous native code to be written. Not all implementations
work this way (they block in the native code) but the same
Java code works for both.
Parameters:
b - the data.
Parameters:
off - the start offset in the data.
Parameters:
len - the number of bytes to write. number of bytes written
exception:
IOException - if an I/O error occurs. In particular,an IOException is thrown if the outputstream is closed. |
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