Qore::DataLineIterator Class Reference

This class defines a line iterator for string data. More...

Inheritance diagram for Qore::DataLineIterator:

Public Member Methods
	constructor (string str, *string eol, bool trim=True)
	creates the DataLineIterator based on the string given More...
	copy ()
	Creates a new DataLineIterator object, based on the same object being iterated in the original object. More...
string	getEncoding ()
	Returns the character encoding for the DataLineIterator. More...
string	getLine ()
	returns the current line in the data or throws an ITERATOR-ERROR exception if the iterator is invalid More...
string	getValue ()
	returns the current line in the data or throws an ITERATOR-ERROR exception if the iterator is invalid More...
int	index ()
	returns the current iterator line number in the data (the first line is line 1) or 0 if not pointing at a valid element More...
bool	next ()
	Moves the current position to the next line in the data; returns False if there are no more lines to read; if the iterator is not pointing at a valid element before this call, the iterator will be positioned to the beginning of the data. More...
	reset ()
	Reset the iterator instance to its initial state. More...
bool	valid ()
	returns True if the iterator is currently pointing at a valid element, False if not More...

Detailed Description

This class defines a line iterator for string data.

Since

Qore 0.8.12

Example: DataLineIterator basic usage

string str = "a2ps-4.13-1332.1.x86_64
a2ps-devel-4.13-1332.1.x86_64
aaa_base-11.3-7.2.x86_64";

DataLineIterator it(str);
while (it.next()) {
    printf("line %d = %n\n", it.index(), it.getValue());
}

line 1 = "a2ps-4.13-1332.1.x86_64"
line 2 = "a2ps-devel-4.13-1332.1.x86_64"
line 3 = "aaa_base-11.3-7.2.x86_64"

See also

Qore::InputStreamLineIterator

Qore::FileLineIterator

Member Function Documentation

constructor()

Qore::DataLineIterator::constructor	(	string	str,
		*string	eol,
		bool	trim = True
	)

creates the DataLineIterator based on the string given

Parameters

str	the string to iterate over; note that if this string is in a non-ascii-compatible character encoding, it will be converted to UTF-8 for processing in the constructor and the UTF-8 version of the string will be used for iterating in this object
eol	the optional end of line character(s) to use to detect lines in the data; if this string is not passed, then the end of line character(s) are detected automatically, and can be either "\n", "\r", or "\r\n"; if this string is passed and has a different character encoding from this object's (as determined by the encoding parameter), then it will be converted to the DataLineIterator's character encoding
trim	if True the string return values for the lines iterated will be trimmed of the eol bytes

Exceptions

ENCODING-CONVERSION-ERROR

this exception could be thrown if the eol argument has a different character encoding from the data's and an error occurs during encoding conversion

copy()

Qore::DataLineIterator::copy

(

)

Creates a new DataLineIterator object, based on the same object being iterated in the original object.

Example:

DataLineIterator ni = i.copy();

getEncoding()

string Qore::DataLineIterator::getEncoding

(

)

Returns the character encoding for the DataLineIterator.

Code Flags:

CONSTANT

Example:

string encoding = f.getEncoding();

Returns

the character encoding for the DataLineIterator

getLine()

string Qore::DataLineIterator::getLine ( )

virtual

returns the current line in the data or throws an ITERATOR-ERROR exception if the iterator is invalid

Returns

the current line in the data or throws an ITERATOR-ERROR exception if the iterator is invalid

Code Flags:

RET_VALUE_ONLY

Example:

while (i.next()) {
    printf("+ %y\n", i.getLine());
}

Exceptions

ITERATOR-ERROR	the iterator is not pointing at a valid element
ITERATOR-THREAD-ERROR	this exception is thrown if this method is called from any thread other than the thread that created the object

See also

DataLineIterator::getValue()

Implements Qore::AbstractLineIterator.

getValue()

string Qore::DataLineIterator::getValue ( )

virtual

returns the current line in the data or throws an ITERATOR-ERROR exception if the iterator is invalid

Returns

the current line in the data or throws an ITERATOR-ERROR exception if the iterator is invalid

Code Flags:

RET_VALUE_ONLY

Example:

while (i.next()) {
    printf("+ %y\n", i.getValue());
}

Exceptions

ITERATOR-ERROR	the iterator is not pointing at a valid element
ITERATOR-THREAD-ERROR	this exception is thrown if this method is called from any thread other than the thread that created the object

See also

DataLineIterator::getLine()

Implements Qore::AbstractLineIterator.

index()

int Qore::DataLineIterator::index ( )

virtual

returns the current iterator line number in the data (the first line is line 1) or 0 if not pointing at a valid element

Returns

the current iterator line number in the data (the first line is line 1) or 0 if not pointing at a valid element

Code Flags:

CONSTANT

Example:

while (i.next()) {
    printf("+ %d: %y\n", i.index(), i.getValue());
}

Implements Qore::AbstractLineIterator.

next()

bool Qore::DataLineIterator::next ( )

virtual

Moves the current position to the next line in the data; returns False if there are no more lines to read; if the iterator is not pointing at a valid element before this call, the iterator will be positioned to the beginning of the data.

This method will return True again after it returns False once if data is not empty, otherwise it will always return False The iterator object should not be used after this method returns False

Returns

False if there are no more lines in the data (in which case the iterator object is invalid and should not be used); True if successful (meaning that the iterator object is valid)

Example:

while (i.next()) {
    printf("line: %y\n", i.getValue());
}

Exceptions

ITERATOR-THREAD-ERROR

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

Implements Qore::AbstractLineIterator.

reset()

Qore::DataLineIterator::reset

(

)

Reset the iterator instance to its initial state.

Reset the iterator instance to its initial state

Example

i.reset();

Exceptions

ITERATOR-THREAD-ERROR

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

valid()

bool Qore::DataLineIterator::valid ( )

virtual

returns True if the iterator is currently pointing at a valid element, False if not

Returns

True if the iterator is currently pointing at a valid element, False if not

Code Flags:

CONSTANT

Example:

if (i.valid())
    printf("current value: %y\n", i.getValue());

Implements Qore::AbstractLineIterator.