JUCE  v5.1.1-3-g1a0b28c73
JUCE API
BufferedInputStream Class Reference

Wraps another input stream, and reads from it using an intermediate buffer. More...

#include <juce_BufferedInputStream.h>

Inheritance diagram for BufferedInputStream:
Collaboration diagram for BufferedInputStream:

Public Member Functions

 BufferedInputStream (InputStream *sourceStream, int bufferSize, bool deleteSourceWhenDestroyed)
 Creates a BufferedInputStream from an input source. More...
 
 BufferedInputStream (InputStream &sourceStream, int bufferSize)
 Creates a BufferedInputStream from an input source. More...
 
 ~BufferedInputStream ()
 Destructor. More...
 
int64 getNumBytesRemaining ()
 Returns the number of bytes available for reading, or a negative value if the remaining length is not known. More...
 
int64 getPosition () override
 Returns the offset of the next byte that will be read from the stream. More...
 
int64 getTotalLength () override
 Returns the total number of bytes available for reading in this stream. More...
 
bool isExhausted () override
 Returns true if the stream has no more data to read. More...
 
char peekByte ()
 Returns the next byte that would be read by a call to readByte() More...
 
int read (void *destBuffer, int maxBytesToRead) override
 Reads some data from the stream into a memory buffer. More...
 
virtual bool readBool ()
 Reads a boolean from the stream. More...
 
virtual char readByte ()
 Reads a byte from the stream. More...
 
virtual int readCompressedInt ()
 Reads an encoded 32-bit number from the stream using a space-saving compressed format. More...
 
virtual double readDouble ()
 Reads eight bytes as a 64-bit floating point value. More...
 
virtual double readDoubleBigEndian ()
 Reads eight bytes as a 64-bit floating point value. More...
 
virtual String readEntireStreamAsString ()
 Tries to read the whole stream and turn it into a string. More...
 
virtual float readFloat ()
 Reads four bytes as a 32-bit floating point value. More...
 
virtual float readFloatBigEndian ()
 Reads four bytes as a 32-bit floating point value. More...
 
virtual int readInt ()
 Reads four bytes from the stream as a little-endian 32-bit value. More...
 
virtual int64 readInt64 ()
 Reads eight bytes from the stream as a little-endian 64-bit value. More...
 
virtual int64 readInt64BigEndian ()
 Reads eight bytes from the stream as a big-endian 64-bit value. More...
 
virtual int readIntBigEndian ()
 Reads four bytes from the stream as a big-endian 32-bit value. More...
 
virtual size_t readIntoMemoryBlock (MemoryBlock &destBlock, ssize_t maxNumBytesToRead=-1)
 Reads from the stream and appends the data to a MemoryBlock. More...
 
virtual String readNextLine ()
 Reads a UTF-8 string from the stream, up to the next linefeed or carriage return. More...
 
virtual short readShort ()
 Reads two bytes from the stream as a little-endian 16-bit value. More...
 
virtual short readShortBigEndian ()
 Reads two bytes from the stream as a little-endian 16-bit value. More...
 
String readString () override
 Reads a zero-terminated UTF-8 string from the stream. More...
 
bool setPosition (int64 newPosition) override
 Tries to move the current read position of the stream. More...
 
virtual void skipNextBytes (int64 numBytesToSkip)
 Reads and discards a number of bytes from the stream. More...
 

Private Member Functions

void ensureBuffered ()
 

Private Attributes

HeapBlock< char > buffer
 
int64 bufferOverlap = 128
 
int bufferSize
 
int64 bufferStart
 
int64 lastReadPos = 0
 
int64 position
 
OptionalScopedPointer< InputStreamsource
 

Detailed Description

Wraps another input stream, and reads from it using an intermediate buffer.

If you're using an input stream such as a file input stream, and making lots of small read accesses to it, it's probably sensible to wrap it in one of these, so that the source stream gets accessed in larger chunk sizes, meaning less work for the underlying stream.

Constructor & Destructor Documentation

◆ BufferedInputStream() [1/2]

BufferedInputStream::BufferedInputStream ( InputStream sourceStream,
int  bufferSize,
bool  deleteSourceWhenDestroyed 
)

Creates a BufferedInputStream from an input source.

Parameters
sourceStreamthe source stream to read from
bufferSizethe size of reservoir to use to buffer the source
deleteSourceWhenDestroyedwhether the sourceStream that is passed in should be deleted by this object when it is itself deleted.

◆ BufferedInputStream() [2/2]

BufferedInputStream::BufferedInputStream ( InputStream sourceStream,
int  bufferSize 
)

Creates a BufferedInputStream from an input source.

Parameters
sourceStreamthe source stream to read from - the source stream must not be deleted until this object has been destroyed.
bufferSizethe size of reservoir to use to buffer the source

◆ ~BufferedInputStream()

BufferedInputStream::~BufferedInputStream ( )

Destructor.

This may also delete the source stream, if that option was chosen when the buffered stream was created.

Member Function Documentation

◆ ensureBuffered()

void BufferedInputStream::ensureBuffered ( )
private

◆ getNumBytesRemaining()

int64 InputStream::getNumBytesRemaining ( )
inherited

Returns the number of bytes available for reading, or a negative value if the remaining length is not known.

See also
getTotalLength

◆ getPosition()

int64 BufferedInputStream::getPosition ( )
overridevirtual

Returns the offset of the next byte that will be read from the stream.

See also
setPosition

Implements InputStream.

◆ getTotalLength()

int64 BufferedInputStream::getTotalLength ( )
overridevirtual

Returns the total number of bytes available for reading in this stream.

Note that this is the number of bytes available from the start of the stream, not from the current position.

If the size of the stream isn't actually known, this will return -1.

See also
getNumBytesRemaining

Implements InputStream.

◆ isExhausted()

bool BufferedInputStream::isExhausted ( )
overridevirtual

Returns true if the stream has no more data to read.

Implements InputStream.

◆ peekByte()

char BufferedInputStream::peekByte ( )

Returns the next byte that would be read by a call to readByte()

◆ read()

int BufferedInputStream::read ( void *  destBuffer,
int  maxBytesToRead 
)
overridevirtual

Reads some data from the stream into a memory buffer.

This is the only read method that subclasses actually need to implement, as the InputStream base class implements the other read methods in terms of this one (although it's often more efficient for subclasses to implement them directly).

Parameters
destBufferthe destination buffer for the data. This must not be null.
maxBytesToReadthe maximum number of bytes to read - make sure the memory block passed in is big enough to contain this many bytes. This value must not be negative.
Returns
the actual number of bytes that were read, which may be less than maxBytesToRead if the stream is exhausted before it gets that far

Implements InputStream.

◆ readBool()

virtual bool InputStream::readBool ( )
virtualinherited

Reads a boolean from the stream.

The bool is encoded as a single byte - non-zero for true, 0 for false. If the stream is exhausted, this will return false.

See also
OutputStream::writeBool

◆ readByte()

virtual char InputStream::readByte ( )
virtualinherited

Reads a byte from the stream.

If the stream is exhausted, this will return zero.

See also
OutputStream::writeByte

◆ readCompressedInt()

virtual int InputStream::readCompressedInt ( )
virtualinherited

Reads an encoded 32-bit number from the stream using a space-saving compressed format.

For small values, this is more space-efficient than using readInt() and OutputStream::writeInt() The format used is: number of significant bytes + up to 4 bytes in little-endian order.

See also
OutputStream::writeCompressedInt()

◆ readDouble()

virtual double InputStream::readDouble ( )
virtualinherited

Reads eight bytes as a 64-bit floating point value.

The raw 64-bit encoding of the double is read from the stream as a little-endian int64. If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeDouble, readFloat

◆ readDoubleBigEndian()

virtual double InputStream::readDoubleBigEndian ( )
virtualinherited

Reads eight bytes as a 64-bit floating point value.

The raw 64-bit encoding of the double is read from the stream as a big-endian int64. If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeDoubleBigEndian, readFloatBigEndian

◆ readEntireStreamAsString()

virtual String InputStream::readEntireStreamAsString ( )
virtualinherited

Tries to read the whole stream and turn it into a string.

This will read from the stream's current position until the end-of-stream. It can read from UTF-8 data, or UTF-16 if it detects suitable header-bytes.

◆ readFloat()

virtual float InputStream::readFloat ( )
virtualinherited

Reads four bytes as a 32-bit floating point value.

The raw 32-bit encoding of the float is read from the stream as a little-endian int. If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeFloat, readDouble

◆ readFloatBigEndian()

virtual float InputStream::readFloatBigEndian ( )
virtualinherited

Reads four bytes as a 32-bit floating point value.

The raw 32-bit encoding of the float is read from the stream as a big-endian int. If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeFloatBigEndian, readDoubleBigEndian

◆ readInt()

virtual int InputStream::readInt ( )
virtualinherited

Reads four bytes from the stream as a little-endian 32-bit value.

If the next four bytes are byte1 to byte4, this returns (byte1 | (byte2 << 8) | (byte3 << 16) | (byte4 << 24)).

If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeInt, readIntBigEndian

◆ readInt64()

virtual int64 InputStream::readInt64 ( )
virtualinherited

Reads eight bytes from the stream as a little-endian 64-bit value.

If the next eight bytes are byte1 to byte8, this returns (byte1 | (byte2 << 8) | (byte3 << 16) | (byte4 << 24) | (byte5 << 32) | (byte6 << 40) | (byte7 << 48) | (byte8 << 56)).

If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeInt64, readInt64BigEndian

◆ readInt64BigEndian()

virtual int64 InputStream::readInt64BigEndian ( )
virtualinherited

Reads eight bytes from the stream as a big-endian 64-bit value.

If the next eight bytes are byte1 to byte8, this returns (byte8 | (byte7 << 8) | (byte6 << 16) | (byte5 << 24) | (byte4 << 32) | (byte3 << 40) | (byte2 << 48) | (byte1 << 56)).

If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeInt64BigEndian, readInt64

◆ readIntBigEndian()

virtual int InputStream::readIntBigEndian ( )
virtualinherited

Reads four bytes from the stream as a big-endian 32-bit value.

If the next four bytes are byte1 to byte4, this returns (byte4 | (byte3 << 8) | (byte2 << 16) | (byte1 << 24)).

If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeIntBigEndian, readInt

◆ readIntoMemoryBlock()

virtual size_t InputStream::readIntoMemoryBlock ( MemoryBlock destBlock,
ssize_t  maxNumBytesToRead = -1 
)
virtualinherited

Reads from the stream and appends the data to a MemoryBlock.

Parameters
destBlockthe block to append the data onto
maxNumBytesToReadif this is a positive value, it sets a limit to the number of bytes that will be read - if it's negative, data will be read until the stream is exhausted.
Returns
the number of bytes that were added to the memory block

◆ readNextLine()

virtual String InputStream::readNextLine ( )
virtualinherited

Reads a UTF-8 string from the stream, up to the next linefeed or carriage return.

This will read up to the next "\n" or "\r\n" or end-of-stream.

After this call, the stream's position will be left pointing to the next character following the line-feed, but the linefeeds aren't included in the string that is returned.

◆ readShort()

virtual short InputStream::readShort ( )
virtualinherited

Reads two bytes from the stream as a little-endian 16-bit value.

If the next two bytes read are byte1 and byte2, this returns (byte1 | (byte2 << 8)). If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeShort, readShortBigEndian

◆ readShortBigEndian()

virtual short InputStream::readShortBigEndian ( )
virtualinherited

Reads two bytes from the stream as a little-endian 16-bit value.

If the next two bytes read are byte1 and byte2, this returns (byte2 | (byte1 << 8)). If the stream is exhausted partway through reading the bytes, this will return zero.

See also
OutputStream::writeShortBigEndian, readShort

◆ readString()

String BufferedInputStream::readString ( )
overridevirtual

Reads a zero-terminated UTF-8 string from the stream.

This will read characters from the stream until it hits a null character or end-of-stream.

See also
OutputStream::writeString, readEntireStreamAsString

Reimplemented from InputStream.

◆ setPosition()

bool BufferedInputStream::setPosition ( int64  newPosition)
overridevirtual

Tries to move the current read position of the stream.

The position is an absolute number of bytes from the stream's start.

Some streams might not be able to do this, in which case they should do nothing and return false. Others might be able to manage it by resetting themselves and skipping to the correct position, although this is obviously a bit slow.

Returns
true if the stream manages to reposition itself correctly
See also
getPosition

Implements InputStream.

◆ skipNextBytes()

virtual void InputStream::skipNextBytes ( int64  numBytesToSkip)
virtualinherited

Reads and discards a number of bytes from the stream.

Some input streams might implement this efficiently, but the base class will just keep reading data until the requisite number of bytes have been done.

Member Data Documentation

◆ buffer

HeapBlock<char> BufferedInputStream::buffer
private

◆ bufferOverlap

int64 BufferedInputStream::bufferOverlap = 128
private

◆ bufferSize

int BufferedInputStream::bufferSize
private

◆ bufferStart

int64 BufferedInputStream::bufferStart
private

◆ lastReadPos

int64 BufferedInputStream::lastReadPos = 0
private

◆ position

int64 BufferedInputStream::position
private

◆ source

OptionalScopedPointer<InputStream> BufferedInputStream::source
private

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