FileOutputStream Class Reference

An output stream that writes into a local file. More...

Inheritance diagram for FileOutputStream:

Public Member Functions

 FileOutputStream (const File &fileToWriteTo, size_t bufferSizeToUse=16384)
 Creates a FileOutputStream. More...
 
 ~FileOutputStream ()
 Destructor. More...
 
const FilegetFile () const
 Returns the file that this stream is writing to. More...
 
const ResultgetStatus () const noexcept
 Returns the status of the file stream. More...
 
bool failedToOpen () const noexcept
 Returns true if the stream couldn't be opened for some reason. More...
 
bool openedOk () const noexcept
 Returns true if the stream opened without problems. More...
 
Result truncate ()
 Attempts to truncate the file to the current write position. More...
 
void flush () override
 If the stream is using a buffer, this will ensure it gets written out to the destination. More...
 
int64 getPosition () override
 Returns the stream's current position. More...
 
bool setPosition (int64) override
 Tries to move the stream's output position. More...
 
bool write (const void *, size_t) override
 Writes a block of data to the stream. More...
 
bool writeRepeatedByte (uint8 byte, size_t numTimesToRepeat) override
 Writes a byte to the output stream a given number of times. More...
 
- Public Member Functions inherited from OutputStream
virtual ~OutputStream ()
 Destructor. More...
 
virtual bool writeByte (char byte)
 Writes a single byte to the stream. More...
 
virtual bool writeBool (bool boolValue)
 Writes a boolean to the stream as a single byte. More...
 
virtual bool writeShort (short value)
 Writes a 16-bit integer to the stream in a little-endian byte order. More...
 
virtual bool writeShortBigEndian (short value)
 Writes a 16-bit integer to the stream in a big-endian byte order. More...
 
virtual bool writeInt (int value)
 Writes a 32-bit integer to the stream in a little-endian byte order. More...
 
virtual bool writeIntBigEndian (int value)
 Writes a 32-bit integer to the stream in a big-endian byte order. More...
 
virtual bool writeInt64 (int64 value)
 Writes a 64-bit integer to the stream in a little-endian byte order. More...
 
virtual bool writeInt64BigEndian (int64 value)
 Writes a 64-bit integer to the stream in a big-endian byte order. More...
 
virtual bool writeFloat (float value)
 Writes a 32-bit floating point value to the stream in a binary format. More...
 
virtual bool writeFloatBigEndian (float value)
 Writes a 32-bit floating point value to the stream in a binary format. More...
 
virtual bool writeDouble (double value)
 Writes a 64-bit floating point value to the stream in a binary format. More...
 
virtual bool writeDoubleBigEndian (double value)
 Writes a 64-bit floating point value to the stream in a binary format. More...
 
virtual bool writeCompressedInt (int value)
 Writes a condensed binary encoding of a 32-bit integer. More...
 
virtual bool writeString (const String &text)
 Stores a string in the stream in a binary format. More...
 
virtual bool writeText (const String &text, bool asUTF16, bool writeUTF16ByteOrderMark)
 Writes a string of text to the stream. More...
 
virtual int64 writeFromInputStream (InputStream &source, int64 maxNumBytesToWrite)
 Reads data from an input stream and writes it to this stream. More...
 
void setNewLineString (const String &newLineString)
 Sets the string to write to the stream when a new line is written. More...
 
const StringgetNewLineString () const noexcept
 Returns the current new-line string that was set by setNewLineString(). More...
 

Additional Inherited Members

- Protected Member Functions inherited from OutputStream
 OutputStream ()
 

Detailed Description

An output stream that writes into a local file.

See also
OutputStream, FileInputStream, File::createOutputStream

Constructor & Destructor Documentation

◆ FileOutputStream()

FileOutputStream::FileOutputStream ( const File fileToWriteTo,
size_t  bufferSizeToUse = 16384 
)

Creates a FileOutputStream.

If the file doesn't exist, it will first be created. If the file can't be created or opened (for example, because the parent directory of the file does not exist), the failedToOpen() method will return true.

If the file already exists when opened, the stream's write-position will be set to the end of the file. To overwrite an existing file, use File::deleteFile() before opening the stream, or use setPosition(0) after it's opened (although this won't truncate the file).

Destroying a FileOutputStream object does not force the operating system to write the buffered data to disk immediately. If this is required you should call flush() before triggering the destructor.

See also
TemporaryFile

◆ ~FileOutputStream()

FileOutputStream::~FileOutputStream ( )

Destructor.

Member Function Documentation

◆ getFile()

const File& FileOutputStream::getFile ( ) const

Returns the file that this stream is writing to.

◆ getStatus()

const Result& FileOutputStream::getStatus ( ) const
noexcept

Returns the status of the file stream.

The result will be ok if the file opened successfully. If an error occurs while opening or writing to the file, this will contain an error message.

◆ failedToOpen()

bool FileOutputStream::failedToOpen ( ) const
noexcept

Returns true if the stream couldn't be opened for some reason.

See also
getResult()

◆ openedOk()

bool FileOutputStream::openedOk ( ) const
noexcept

◆ truncate()

Result FileOutputStream::truncate ( )

Attempts to truncate the file to the current write position.

To truncate a file to a specific size, first use setPosition() to seek to the appropriate location, and then call this method.

◆ flush()

void FileOutputStream::flush ( )
overridevirtual

If the stream is using a buffer, this will ensure it gets written out to the destination.

Implements OutputStream.

◆ getPosition()

int64 FileOutputStream::getPosition ( )
overridevirtual

Returns the stream's current position.

See also
setPosition

Implements OutputStream.

◆ setPosition()

bool FileOutputStream::setPosition ( int64  newPosition)
overridevirtual

Tries to move the stream's output position.

Not all streams will be able to seek to a new position - this will return false if it fails to work.

See also
getPosition

Implements OutputStream.

◆ write()

bool FileOutputStream::write ( const void *  dataToWrite,
size_t  numberOfBytes 
)
overridevirtual

Writes a block of data to the stream.

When creating a subclass of OutputStream, this is the only write method that needs to be overloaded - the base class has methods for writing other types of data which use this to do the work.

Parameters
dataToWritethe target buffer to receive the data. This must not be null.
numberOfBytesthe number of bytes to write.
Returns
false if the write operation fails for some reason

Implements OutputStream.

◆ writeRepeatedByte()

bool FileOutputStream::writeRepeatedByte ( uint8  byte,
size_t  numTimesToRepeat 
)
overridevirtual

Writes a byte to the output stream a given number of times.

Returns
false if the write operation fails for some reason

Reimplemented from OutputStream.


The documentation for this class was generated from the following file: