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## com.trolltech.qt.core
Class QTemporaryFile

    java.lang.Object
      com.trolltech.qt.internal.QSignalEmitterInternal
          com.trolltech.qt.QSignalEmitter
              com.trolltech.qt.QtJambiObject
                  com.trolltech.qt.core.QObject
                      com.trolltech.qt.core.QIODevice
                          com.trolltech.qt.core.QFile
                              com.trolltech.qt.core.QTemporaryFile

All Implemented Interfaces:
  QtJambiInterface

    public class QTemporaryFile

extends QFile

The `QTemporaryFile` class is an I/O device that operates on temporary files. `QTemporaryFile` is used to create unique temporary files safely. The file itself is created by calling `open()`. The name of the temporary file is guaranteed to be unique (i.e., you are guaranteed to not overwrite an existing file), and the file will subsequently be removed upon destruction of the `QTemporaryFile` object. This is an important technique that avoids data corruption for applications that store data in temporary files. The file name is either auto-generated, or created based on a template, which is passed to `QTemporaryFile`'s constructor.

Example:

            {
                QTemporaryFile file = new QTemporaryFile();
                if (file.open()) {
                    // file.fileName() returns the unique file name
                }

                // the QTemporaryFile destructor removes the temporary file
            }

Reopening a `QTemporaryFile` after calling `close()` is safe. For as long as the `QTemporaryFile` object itself is not destroyed, the unique temporary file will exist and be kept open internally by `QTemporaryFile`.

The file name of the temporary file can be found by calling fileName(). Note that this is only defined while the file is open; the function returns an empty string before the file is opened and after it is closed.

A temporary file will have some static part of the name and some part that is calculated to be unique. The default filename `qt_temp` will be placed into the temporary path as returned by `QDir::tempPath()`. If you specify your own filename, a relative file path will not be placed in the temporary directory by default, but be relative to the current working directory.

Specified filenames can contain the following template `XXXXXX`, which will be replaced by the auto-generated portion of the filename. Note that the template is case sensitive. If the template is not present in the filename, `QTemporaryFile` appends the generated part to the filename given.

See also:
  `QDir::tempPath()`, and `QFile`.

Nested Class Summary

Nested classes/interfaces inherited from class com.trolltech.qt.core.QFile
`QFile.FileError, QFile.MemoryMapFlags, QFile.Permission, QFile.Permissions`

Nested classes/interfaces inherited from class com.trolltech.qt.core.QIODevice
`QIODevice.OpenMode, QIODevice.OpenModeFlag`

Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
`QSignalEmitter.AbstractSignal, QSignalEmitter.Signal0, QSignalEmitter.Signal1, QSignalEmitter.Signal2, QSignalEmitter.Signal3, QSignalEmitter.Signal4, QSignalEmitter.Signal5, QSignalEmitter.Signal6, QSignalEmitter.Signal7, QSignalEmitter.Signal8, QSignalEmitter.Signal9`

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.core.QIODevice
`aboutToClose, bytesWritten, readChannelFinished, readyRead`

Fields inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
`currentSender`

Constructor Summary
`QTemporaryFile()` Constructs a `QTemporaryFile` in `QDir::tempPath()`, using the file template "qt_temp.XXXXXX".
`QTemporaryFile(QObject parent)` Constructs a `QTemporaryFile` (with the given `parent`) in `QDir::tempPath()`, using the file template "qt_temp.XXXXXX".
`QTemporaryFile(java.lang.String templateName)` Constructs a `QTemporaryFile` with a template filename of `templateName`.
`QTemporaryFile(java.lang.String templateName, QObject parent)` Constructs a `QTemporaryFile` with a template filename of `templateName` and the specified `parent`.

Method Summary
`boolean` | `autoRemove()` Returns true if the `QTemporaryFile` is in auto remove mode.
`static QTemporaryFile` | `createLocalFile(QFile file)` If `file` is not on a local disk, a temporary file is created on a local disk, `file` is copied into the temporary local file, and a pointer to the temporary local file is returned.
`static QTemporaryFile` | `createLocalFile(java.lang.String fileName)` Works on the given `fileName` rather than an existing `QFile` object.
`java.lang.String` | `fileTemplate()` Returns the set file template.
`boolean` | `open()` A `QTemporaryFile` will always be opened in `QIODevice::ReadWrite` mode, this allows easy access to the data in the file.
`void` | `setAutoRemove(boolean b)` Sets the `QTemporaryFile` into auto-remove mode if `b` is true.
`void` | `setFileTemplate(java.lang.String name)` Sets the static portion of the file name to `name`.
`java.lang.String` | `uniqueFilename()` Returns the complete unique filename backing the `QTemporaryFile` object.

Methods inherited from class com.trolltech.qt.core.QFile
`copy, copy, decodeName, decodeName, encodeName, error, exists, exists, fileName, flush, handle, link, link, open, open, open, permissions, permissions, remove, remove, rename, rename, resize, resize, setFileName, setPermissions, setPermissions, setPermissions, setPermissions, symLinkTarget, symLinkTarget, unsetError`

Methods inherited from class com.trolltech.qt.core.QIODevice
`atEnd, bytesAvailable, bytesToWrite, canReadLine, close, errorString, getByte, isOpen, isReadable, isSequential, isTextModeEnabled, isWritable, open, openMode, peek, peek, pos, putByte, read, read, readAll, readData, readLine, readLine, readLine, readLineData, reset, seek, setErrorString, setOpenMode, setOpenMode, setTextModeEnabled, size, ungetByte, waitForBytesWritten, waitForReadyRead, write, write, writeData`

Methods inherited from class com.trolltech.qt.core.QObject
`childEvent, children, connectSlotsByName, customEvent, disposeLater, dumpObjectInfo, dumpObjectTree, dynamicPropertyNames, event, eventFilter, findChild, findChild, findChild, findChildren, findChildren, findChildren, findChildren, indexOfProperty, installEventFilter, isWidgetType, killTimer, moveToThread, objectName, parent, properties, property, removeEventFilter, setObjectName, setParent, setProperty, startTimer, timerEvent, toString, userProperty`

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, wait, wait, wait`

Methods inherited from interface com.trolltech.qt.QtJambiInterface
`disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership`

Constructor Detail

### QTemporaryFile

    public QTemporaryFile()

  Constructs a `QTemporaryFile` in `QDir::tempPath()`, using the file template "qt_temp.XXXXXX". The file is stored in the system's temporary directory.

See also:
  `setFileTemplate()`, and `QDir::tempPath()`.

### QTemporaryFile

    public QTemporaryFile(QObject parent)

  Constructs a `QTemporaryFile` (with the given `parent`) in `QDir::tempPath()`, using the file template "qt_temp.XXXXXX".

See also:
  `setFileTemplate()`.

### QTemporaryFile

    public QTemporaryFile(java.lang.String templateName)

  Constructs a `QTemporaryFile` with a template filename of `templateName`. Upon opening the temporary file this will be used to create a unique filename. If the `templateName` does not contain XXXXXX it will automatically be appended and used as the dynamic portion of the filename.

  If `templateName` is a relative path, the path will be relative to the current working directory. You can use `QDir::tempPath()` to construct `templateName` if you want use the system's temporary directory.

See also:
  `open()`, and `fileTemplate()`.

### QTemporaryFile

    public QTemporaryFile(java.lang.String templateName,
                          QObject parent)

  Constructs a `QTemporaryFile` with a template filename of `templateName` and the specified `parent`. Upon opening the temporary file this will be used to create a unique filename. If the `templateName` does end in XXXXXX it will automatically be appended and used as the dynamic portion of the filename.

  If `templateName` is a relative path, the path will be relative to the current working directory. You can use `QDir::tempPath()` to construct `templateName` if you want use the system's temporary directory.

See also:
  `open()`, and `fileTemplate()`.

Method Detail

### autoRemove

    public final boolean autoRemove()

  Returns true if the `QTemporaryFile` is in auto remove mode. Auto-remove mode will automatically delete the filename from disk upon destruction. This makes it very easy to create your `QTemporaryFile` object on the stack, fill it with data, read from it, and finally on function return it will automatically clean up after itself.

  Auto-remove is on by default.

See also:
  `setAutoRemove()`, and `remove()`.

### uniqueFilename

    public final java.lang.String uniqueFilename()

  Returns the complete unique filename backing the `QTemporaryFile` object. This string is null before the `QTemporaryFile` is opened, afterwards it will contain the `fileTemplate()` plus additional characters to make it unique.

See also:
  `fileTemplate()`.

### fileTemplate

    public final java.lang.String fileTemplate()

  Returns the set file template. The default file template will be called qt_temp and be placed in `QDir::tempPath()`.

See also:
  `setFileTemplate()`.

### open

    public final boolean open()

  A `QTemporaryFile` will always be opened in `QIODevice::ReadWrite` mode, this allows easy access to the data in the file. This function will return true upon success and will set the fileName() to the unique filename used.

See also:
  fileName().

### setAutoRemove

    public final void setAutoRemove(boolean b)

  Sets the `QTemporaryFile` into auto-remove mode if `b` is true.

  Auto-remove is on by default.

See also:
  `autoRemove()`, and `remove()`.

### setFileTemplate

    public final void setFileTemplate(java.lang.String name)

  Sets the static portion of the file name to `name`. If the file template ends in XXXXXX that will automatically be replaced with the unique part of the filename, otherwise a filename will be determined automatically based on the static portion specified.

  If `name` contains a relative file path, the path will be relative to the current working directory. You can use `QDir::tempPath()` to construct `name` if you want use the system's temporary directory.

See also:
  `fileTemplate()`.

### createLocalFile

    public static QTemporaryFile createLocalFile(QFile file)

  If `file` is not on a local disk, a temporary file is created on a local disk, `file` is copied into the temporary local file, and a pointer to the temporary local file is returned. If `file` is already on a local disk, a copy is not created and 0 is returned.

### createLocalFile

    public static QTemporaryFile createLocalFile(java.lang.String fileName)

  Works on the given `fileName` rather than an existing `QFile` object.

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