|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectcom.trolltech.qt.internal.QSignalEmitterInternal
com.trolltech.qt.QSignalEmitter
com.trolltech.qt.QtJambiObject
com.trolltech.qt.core.QAbstractFileEngine
public class QAbstractFileEngine
The QAbstractFileEngine class provides an abstraction for accessing the filesystem. The QDir
, QFile
, and QFileInfo
classes all make use of a QAbstractFileEngine internally. If you create your own QAbstractFileEngine subclass (and register it with Qt by creating a QAbstractFileEngineHandler
subclass), your file engine will be used when the path is one that your file engine handles.
A QAbstractFileEngine refers to one file or one directory. If the referent is a file, the setFileName()
, rename()
, and remove()
functions are applicable. If the referent is a directory the mkdir()
, rmdir()
, and entryList()
functions are applicable. In all cases the caseSensitive()
, isRelativePath()
, fileFlags()
, ownerId()
, owner()
, and fileTime()
functions are applicable.
A QAbstractFileEngine subclass can be created to do synchronous network I/O based file system operations, local file system operations, or to operate as a resource system to access file based resources.
QAbstractFileEngineHandler
.
Nested Class Summary | |
---|---|
static class |
QAbstractFileEngine.Extension
This enum describes the types of extensions that the file engine can support. |
static class |
QAbstractFileEngine.FileFlag
The permissions and types of a file, suitable for OR'ing together. |
static class |
QAbstractFileEngine.FileFlags
|
static class |
QAbstractFileEngine.FileName
These values are used to request a file name in a particular format. |
static class |
QAbstractFileEngine.FileOwner
See also. owner() , ownerId() , and setFileName() . |
static class |
QAbstractFileEngine.FileTime
These are used by the fileTime() function. |
Nested classes/interfaces inherited from class com.trolltech.qt.internal.QSignalEmitterInternal |
---|
com.trolltech.qt.internal.QSignalEmitterInternal.AbstractSignalInternal |
Field Summary |
---|
Fields inherited from class com.trolltech.qt.internal.QSignalEmitterInternal |
---|
currentSender |
Constructor Summary | |
---|---|
protected |
QAbstractFileEngine()
Constructs a new QAbstractFileEngine that does not refer to any file or directory. |
Method Summary | |
---|---|
static void |
addSearchPathForResourceEngine(java.lang.String path)
Adds path to the set of paths in which Qt Jambi should search for resources. |
boolean |
atEnd()
Returns true if the current position is at the end of the file; otherwise, returns false. |
boolean |
caseSensitive()
Should return true if the underlying file system is case-sensitive; otherwise return false. |
boolean |
close()
Closes the file, returning true if successful; otherwise returns false. |
boolean |
copy(java.lang.String newName)
Copies the contents of this file to a file with the name newName. |
static QAbstractFileEngine |
create(java.lang.String fileName)
Creates and returns a QAbstractFileEngine suitable for processing fileName. |
java.util.List |
entryList(QDir.Filters filters,
java.util.List filterNames)
Requests that a list of all the files matching the filters list based on the filterNames in the file engine's directory are returned. |
QFile.FileError |
error()
Returns the QFile::FileError that resulted from the last failed operation. |
java.lang.String |
errorString()
Returns the human-readable message appropriate to the current error reported by error() . |
QAbstractFileEngine.FileFlags |
fileFlags()
This function should return the set of OR'd flags that are true for the file engine's file, and that are in the type's OR'd members. |
QAbstractFileEngine.FileFlags |
fileFlags(QAbstractFileEngine.FileFlag[] type)
This is an overloaded method provided for convenience. |
QAbstractFileEngine.FileFlags |
fileFlags(QAbstractFileEngine.FileFlags type)
This function should return the set of OR'd flags that are true for the file engine's file, and that are in the type's OR'd members. |
java.lang.String |
fileName()
Return the file engine's current file name in the format specified by file. |
java.lang.String |
fileName(QAbstractFileEngine.FileName file)
Return the file engine's current file name in the format specified by file. |
QDateTime |
fileTime(QAbstractFileEngine.FileTime time)
If time is CreationTime, return when the file was created. |
boolean |
flush()
Flushes the open file, returning true if successful; otherwise returns false. |
int |
handle()
Returns the native file handle for this file engine. |
boolean |
isRelativePath()
Return true if the file referred to by this file engine has a relative path; otherwise return false. |
boolean |
isSequential()
Returns true if the file is a sequential access device; returns false if the file is a direct access device. |
boolean |
link(java.lang.String newName)
Creates a link from the file currently specified by fileName() to newName. |
boolean |
mkdir(java.lang.String dirName,
boolean createParentDirectories)
Requests that the directory dirName be created. |
boolean |
open(QIODevice.OpenMode openMode)
Opens the file in the specified mode. |
boolean |
open(QIODevice.OpenModeFlag[] openMode)
This is an overloaded method provided for convenience. |
java.lang.String |
owner(QAbstractFileEngine.FileOwner arg__1)
If owner is OwnerUser return the name of the user who owns the file. |
int |
ownerId(QAbstractFileEngine.FileOwner arg__1)
If owner is OwnerUser return the ID of the user who owns the file. |
long |
pos()
Returns the current file position. |
long |
read(QNativePointer data,
long maxlen)
Reads a number of characters from the file into data. |
long |
readLine(QNativePointer data,
long maxlen)
This function reads one line, terminated by a '\n' character, from the file info data. |
boolean |
remove()
Requests that the file is deleted from the file system. |
static void |
removeSearchPathForResourceEngine(java.lang.String path)
Removes path from the set of paths in which Qt Jambi searches for resources. |
boolean |
rename(java.lang.String newName)
Requests that the file be renamed to newName in the file system. |
boolean |
rmdir(java.lang.String dirName,
boolean recurseParentDirectories)
Requests that the directory dirName is deleted from the file system. |
boolean |
seek(long pos)
Sets the file position to the given offset. |
protected void |
setError(QFile.FileError error,
java.lang.String str)
Sets the error type to error, and the error string to errorString. |
void |
setFileName(java.lang.String file)
Sets the file engine's file name to file. |
boolean |
setPermissions(int perms)
Requests that the file's permissions be set to perms. |
boolean |
setSize(long size)
Requests that the file be set to size size. |
long |
size()
Returns the size of the file. |
boolean |
supportsExtension(QAbstractFileEngine.Extension extension)
This virtual function returns true if the file engine supports extension; otherwise, false is returned. |
long |
write(QNativePointer data,
long len)
Writes len bytes from data to the file. |
Methods inherited from class com.trolltech.qt.QtJambiObject |
---|
dispose, disposed, equals, finalize, reassignNativeResources, tr, tr, tr |
Methods inherited from class com.trolltech.qt.QSignalEmitter |
---|
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread |
Methods inherited from class com.trolltech.qt.internal.QSignalEmitterInternal |
---|
__qt_signalInitialization |
Methods inherited from class java.lang.Object |
---|
clone, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Methods inherited from interface com.trolltech.qt.QtJambiInterface |
---|
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership |
Constructor Detail |
---|
protected QAbstractFileEngine()
setFileName()
.
Method Detail |
---|
public final boolean atEnd()
This function bases its behavior on calling extension() with AtEndExtension
. If the engine does not support this extension, false is returned.
supportsExtension()
, and QFile::atEnd().
public final QFile.FileError error()
QFile::FileError
that resulted from the last failed operation. If QFile::UnspecifiedError
is returned, QFile
will use its own idea of the error status. setError()
, QFile::FileError
, and errorString()
.
public final java.lang.String errorString()
error()
. If no suitable string is available, an empty string is returned. error()
.
protected final void setError(QFile.FileError error, java.lang.String str)
QFile::error()
, QIODevice::errorString()
, and QIODevice::setErrorString()
.
public boolean caseSensitive()
This virtual function must be reimplemented by all subclasses.
public boolean close()
The default implementation always returns false.
public boolean copy(java.lang.String newName)
public java.util.List entryList(QDir.Filters filters, java.util.List filterNames)
Should return an empty list if the file engine refers to a file rather than a directory, or if the directory is unreadable or does not exist or if nothing matches the specifications.
This virtual function must be reimplemented by all subclasses.
setFileName()
.
public final QAbstractFileEngine.FileFlags fileFlags(QAbstractFileEngine.FileFlag[] type)
public final QAbstractFileEngine.FileFlags fileFlags()
In your reimplementation you can use the type argument as an optimization hint and only return the OR'd set of members that are true and that match those in type; in other words you can ignore any members not mentioned in type, thus avoiding some potentially expensive lookups or system calls.
This virtual function must be reimplemented by all subclasses.
setFileName()
.
public QAbstractFileEngine.FileFlags fileFlags(QAbstractFileEngine.FileFlags type)
In your reimplementation you can use the type argument as an optimization hint and only return the OR'd set of members that are true and that match those in type; in other words you can ignore any members not mentioned in type, thus avoiding some potentially expensive lookups or system calls.
This virtual function must be reimplemented by all subclasses.
setFileName()
.
public final java.lang.String fileName()
If you don't handle some FileName possibilities, return the file name set in setFileName()
when an unhandled format is requested.
This virtual function must be reimplemented by all subclasses.
setFileName()
, and FileName
.
public java.lang.String fileName(QAbstractFileEngine.FileName file)
If you don't handle some FileName possibilities, return the file name set in setFileName()
when an unhandled format is requested.
This virtual function must be reimplemented by all subclasses.
setFileName()
, and FileName
.
public QDateTime fileTime(QAbstractFileEngine.FileTime time)
This virtual function must be reimplemented by all subclasses.
setFileName()
, QDateTime
, QDateTime::isValid()
, and FileTime
.
public boolean flush()
The default implementation always returns false.
public int handle()
public boolean isRelativePath()
This virtual function must be reimplemented by all subclasses.
setFileName()
.
public boolean isSequential()
Operations involving size()
and seek(int) are not valid on sequential devices.
public boolean link(java.lang.String newName)
fileName()
to newName. What a link is depends on the underlying filesystem (be it a shortcut on Windows or a symbolic link on Unix). Returns true if successful; otherwise returns false.
public boolean mkdir(java.lang.String dirName, boolean createParentDirectories)
This virtual function must be reimplemented by all subclasses.
setFileName()
, rmdir()
, and isRelativePath()
.
public final boolean open(QIODevice.OpenModeFlag[] openMode)
public boolean open(QIODevice.OpenMode openMode)
The mode is an OR combination of QIODevice::OpenMode and QIODevice::HandlingMode values.
public java.lang.String owner(QAbstractFileEngine.FileOwner arg__1)
This virtual function must be reimplemented by all subclasses.
ownerId()
, setFileName()
, and FileOwner
.
public int ownerId(QAbstractFileEngine.FileOwner arg__1)
This virtual function must be reimplemented by all subclasses.
owner()
, setFileName()
, and FileOwner
.
public long pos()
This is the position of the data read/write head of the file.
public long read(QNativePointer data, long maxlen)
Returns -1 if a fatal error occurs, or 0 if there are no bytes to read.
public long readLine(QNativePointer data, long maxlen)
public boolean remove()
This virtual function must be reimplemented by all subclasses.
setFileName()
, and rmdir()
.
public boolean rename(java.lang.String newName)
This virtual function must be reimplemented by all subclasses.
setFileName()
.
public boolean rmdir(java.lang.String dirName, boolean recurseParentDirectories)
This virtual function must be reimplemented by all subclasses.
setFileName()
, remove()
, mkdir()
, and isRelativePath()
.
public boolean seek(long pos)
The offset is from the beginning of the file, unless the file is sequential.
isSequential()
.
public void setFileName(java.lang.String file)
This virtual function must be reimplemented by all subclasses.
fileName()
, and rename()
.
public boolean setPermissions(int perms)
QAbstractFileEngine::PermsMask
being honored. If the operations succceeds return true; otherwise return false; This virtual function must be reimplemented by all subclasses.
size()
.
public boolean setSize(long size)
This virtual function must be reimplemented by all subclasses.
size()
.
public long size()
setSize()
.
public boolean supportsExtension(QAbstractFileEngine.Extension extension)
public long write(QNativePointer data, long len)
public static QAbstractFileEngine create(java.lang.String fileName)
You should not need to call this function; use QFile
, QFileInfo
or QDir
directly instead.
If you reimplemnt this function, it should only return file engines that knows how to handle fileName; otherwise, it should return 0.
QAbstractFileEngineHandler
.
public static void addSearchPathForResourceEngine(java.lang.String path)
public static void removeSearchPathForResourceEngine(java.lang.String path)
|
|||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | ||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |