Qore::StringInputStream Class Reference

This class implements the InputStream interface for reading bytes from a String variable. More...

Inheritance diagram for Qore::StringInputStream:

Public Member Methods
	constructor (string src)
	Creates the StringInputStream based on the String given. More...
string	getEncoding ()
	Returns the character encoding for the StringInputStream. More...
int	peek ()
	Peeks the next byte available from the input stream; returns -1 if no more data available. More...
*binary	read (int limit)
	Reads bytes (up to a specified limit) from the input stream; returns NOTHING if there are no more bytes in the stream. More...
Public Member Methods inherited from Qore::InputStream
	constructor ()
	Constructor. More...
Public Member Methods inherited from Qore::StreamBase
	constructor ()
	Throws an exception if called directly; this class can only be instantiated by builtin subclasses. More...
int	getThreadId ()
	Get the currently assigned thread id or -1 if not assigned to any thread.
nothing	reassignThread ()
	Reassigns current thread as thread used for stream manipulation. More...
nothing	unassignThread ()
	Unassigns current thread as thread used for stream manipulation. More...

Detailed Description

This class implements the InputStream interface for reading bytes from a String variable.

Since

Qore 0.8.13

Example: StringInputStream basic usage

string src = "abc";
StringInputStream sis(src);
*binary b;
while (b = sis.read(2)) {
    printf("read %s\n", make_hex_string(b));
}
 
read 6162
read 63

Note

stream classes are not designed to be accessed from multiple threads; they have been implemented without locking for fast and efficient use when used from a single thread. For methods that would be unsafe to use in another thread, any use of such methods in threads other than the thread where the constructor was called will cause a STREAM-THREAD-ERROR to be thrown, unless the stream is handed off to another thread using the StreamBase::unassignThread() method in the thread that currently owns the stream, and the StreamBase::reassignThread() method in the new thread.

See also

StreamReader for a class that can be used to read various kinds of data from an InputStream

Member Function Documentation

constructor()

Qore::StringInputStream::constructor

(

string

src

)

Creates the StringInputStream based on the String given.

Parameters

src	the String to read bytes from

getEncoding()

string Qore::StringInputStream::getEncoding

(

)

Returns the character encoding for the StringInputStream.

Code Flags:

CONSTANT

Example:

string src = "xyz";
StringInputStream is(src);
string encoding = is.getEncoding();

Returns

the character encoding for the StringInputStream

peek()

int Qore::StringInputStream::peek ( )

virtual

Peeks the next byte available from the input stream; returns -1 if no more data available.

Returns

the next byte available from the input stream or -1 if no more data is available

Example:

string src = "xyz";
StringInputStream is(src);
printf("peek: %d\n", is.peek());
*binary b = is.read(3);
printf("peek: %d\n", is.peek());
 
peek 120
peek -1

Exceptions

STREAM-THREAD-ERROR

this exception is thrown if this method is called from any thread other than the thread that created the object

Implements Qore::InputStream.

read()

*binary Qore::StringInputStream::read ( int  limit )

virtual

Reads bytes (up to a specified limit) from the input stream; returns NOTHING if there are no more bytes in the stream.

Parameters

limit

the maximum number of bytes to read

Returns

the read bytes (the length is between 1 and `limit` inclusive) or NOTHING if no more bytes are available

Example:

string src = "xyz";
StringInputStream is(src);
*binary b;
while (b = is.read(2)) {
    printf("read %s\n", make_hex_string(b));
}
 
read 7879
read 7a

Exceptions

INPUT-STREAM-ERROR	limit is not positive
STREAM-THREAD-ERROR	this exception is thrown if this method is called from any thread other than the thread that created the object

Implements Qore::InputStream.