The base class for streams that read data. More...
Inherited by BufferedInputStream, FileInputStream, GZIPDecompressorInputStream, MemoryInputStream, and SubregionStream.
Public Member Functions | |
| virtual | ~InputStream () |
| Destructor. | |
| virtual int64 | getTotalLength ()=0 |
| Returns the total number of bytes available for reading in this stream. | |
| virtual bool | isExhausted ()=0 |
| Returns true if the stream has no more data to read. | |
| virtual int | read (void *destBuffer, int maxBytesToRead)=0 |
| Reads a set of bytes from the stream into a memory buffer. | |
| virtual char | readByte () |
| Reads a byte from the stream. | |
| virtual bool | readBool () |
| Reads a boolean from the stream. | |
| virtual short | readShort () |
| Reads two bytes from the stream as a little-endian 16-bit value. | |
| virtual short | readShortBigEndian () |
| Reads two bytes from the stream as a little-endian 16-bit value. | |
| virtual int | readInt () |
| Reads four bytes from the stream as a little-endian 32-bit value. | |
| virtual int | readIntBigEndian () |
| Reads four bytes from the stream as a big-endian 32-bit value. | |
| virtual int64 | readInt64 () |
| Reads eight bytes from the stream as a little-endian 64-bit value. | |
| virtual int64 | readInt64BigEndian () |
| Reads eight bytes from the stream as a big-endian 64-bit value. | |
| virtual float | readFloat () |
| Reads four bytes as a 32-bit floating point value. | |
| virtual float | readFloatBigEndian () |
| Reads four bytes as a 32-bit floating point value. | |
| virtual double | readDouble () |
| Reads eight bytes as a 64-bit floating point value. | |
| virtual double | readDoubleBigEndian () |
| Reads eight bytes as a 64-bit floating point value. | |
| virtual int | readCompressedInt () |
| Reads an encoded 32-bit number from the stream using a space-saving compressed format. | |
| virtual String | readNextLine () |
| Reads a UTF8 string from the stream, up to the next linefeed or carriage return. | |
| virtual String | readString () |
| Reads a zero-terminated UTF8 string from the stream. | |
| virtual String | readEntireStreamAsString () |
| Tries to read the whole stream and turn it into a string. | |
| virtual int | readIntoMemoryBlock (MemoryBlock &destBlock, int maxNumBytesToRead=-1) |
| Reads from the stream and appends the data to a MemoryBlock. | |
| virtual int64 | getPosition ()=0 |
| Returns the offset of the next byte that will be read from the stream. | |
| virtual bool | setPosition (int64 newPosition)=0 |
| Tries to move the current read position of the stream. | |
| virtual void | skipNextBytes (int64 numBytesToSkip) |
| Reads and discards a number of bytes from the stream. | |
Protected Member Functions | |
| InputStream () noexcept | |
The base class for streams that read data.
Input and output streams are used throughout the library - subclasses can override some or all of the virtual functions to implement their behaviour.
| virtual InputStream::~InputStream | ( | ) | [virtual] |
Destructor.
| InputStream::InputStream | ( | ) | [protected] |
| virtual int64 InputStream::getTotalLength | ( | ) | [pure virtual] |
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 may return -1.
Implemented in FileInputStream, BufferedInputStream, GZIPDecompressorInputStream, MemoryInputStream, and SubregionStream.
| virtual bool InputStream::isExhausted | ( | ) | [pure virtual] |
Returns true if the stream has no more data to read.
Implemented in FileInputStream, BufferedInputStream, GZIPDecompressorInputStream, MemoryInputStream, and SubregionStream.
| virtual int InputStream::read | ( | void * | destBuffer, |
| int | maxBytesToRead | ||
| ) | [pure virtual] |
Reads a set of bytes 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).
| destBuffer | the destination buffer for the data |
| maxBytesToRead | the maximum number of bytes to read - make sure the memory block passed in is big enough to contain this many bytes. |
Implemented in FileInputStream, BufferedInputStream, GZIPDecompressorInputStream, MemoryInputStream, and SubregionStream.
| virtual char InputStream::readByte | ( | ) | [virtual] |
Reads a byte from the stream.
If the stream is exhausted, this will return zero.
| virtual bool InputStream::readBool | ( | ) | [virtual] |
Reads a boolean from the stream.
The bool is encoded as a single byte - 1 for true, 0 for false.
If the stream is exhausted, this will return false.
| virtual short InputStream::readShort | ( | ) | [virtual] |
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.
| virtual short InputStream::readShortBigEndian | ( | ) | [virtual] |
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.
| virtual int InputStream::readInt | ( | ) | [virtual] |
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.
| virtual int InputStream::readIntBigEndian | ( | ) | [virtual] |
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.
| virtual int64 InputStream::readInt64 | ( | ) | [virtual] |
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.
| virtual int64 InputStream::readInt64BigEndian | ( | ) | [virtual] |
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.
| virtual float InputStream::readFloat | ( | ) | [virtual] |
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.
| virtual float InputStream::readFloatBigEndian | ( | ) | [virtual] |
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.
| virtual double InputStream::readDouble | ( | ) | [virtual] |
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.
| virtual double InputStream::readDoubleBigEndian | ( | ) | [virtual] |
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.
| virtual int InputStream::readCompressedInt | ( | ) | [virtual] |
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.
| virtual String InputStream::readNextLine | ( | ) | [virtual] |
Reads a UTF8 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.
| virtual String InputStream::readString | ( | ) | [virtual] |
Reads a zero-terminated UTF8 string from the stream.
This will read characters from the stream until it hits a zero character or end-of-stream.
Reimplemented in BufferedInputStream.
| virtual String InputStream::readEntireStreamAsString | ( | ) | [virtual] |
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, and will try to make an educated guess about whether it's unicode or an 8-bit encoding.
| virtual int InputStream::readIntoMemoryBlock | ( | MemoryBlock & | destBlock, |
| int | maxNumBytesToRead = -1 |
||
| ) | [virtual] |
Reads from the stream and appends the data to a MemoryBlock.
| destBlock | the block to append the data onto |
| maxNumBytesToRead | if 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. |
| virtual int64 InputStream::getPosition | ( | ) | [pure virtual] |
Returns the offset of the next byte that will be read from the stream.
Implemented in FileInputStream, BufferedInputStream, GZIPDecompressorInputStream, MemoryInputStream, and SubregionStream.
| virtual bool InputStream::setPosition | ( | int64 | newPosition ) | [pure virtual] |
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.
Implemented in FileInputStream, BufferedInputStream, GZIPDecompressorInputStream, MemoryInputStream, and SubregionStream.
| virtual void InputStream::skipNextBytes | ( | int64 | numBytesToSkip ) | [virtual] |
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.
