Qore Programming Language Reference Manual  1.8.0
Qore::StringOutputStream Class Reference

This class implements the OutputStream interface for writing bytes to a String buffer. More...

Inheritance diagram for Qore::StringOutputStream:

Public Member Methods

nothing close ()
 Closes the output stream and releases any resources. More...
 
 constructor ()
 Creates the StringOutputStream. More...
 
 constructor (string encoding)
 Creates the StringOutputStream. More...
 
string getData ()
 Returns the data written to the stream, clearing the internal buffer. More...
 
string getEncoding ()
 Returns the character encoding for the StringOutputStream. More...
 
bool hasData ()
 Returns True if the stream already has data. More...
 
nothing write (binary data)
 Writes bytes to the output stream. More...
 
- Public Member Methods inherited from Qore::OutputStream
 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 OutputStream interface for writing bytes to a String buffer.

Example: StringOutputStream basic usage
StringOutputStream sos();
sos.write(<41>);
sos.write(<42>);
sos.write(<43>);
sos.getData(); # returns "ABC"
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
StreamWriter for a class that can be used to write various kinds of data to an OutputStream
Since
Qore 0.8.13

Member Function Documentation

◆ close()

nothing Qore::StringOutputStream::close ( )
virtual

Closes the output stream and releases any resources.

Any methods called on a closed output stream will throw an exception.

Exceptions
OUTPUT-STREAM-CLOSED-ERRORthe output stream has already been closed
STREAM-THREAD-ERRORthis exception is thrown if this method is called from any thread other than the thread that created the object

Implements Qore::OutputStream.

◆ constructor() [1/2]

Qore::StringOutputStream::constructor ( )

Creates the StringOutputStream.

This variant assumes the Default Character Encoding for the string

Note
raw binary data is written to the output stream, so it's up to the caller to ensure that only valid character data for the given encoding is written to the StringOutputStream object, otherwise a string with invalid character data will be returned by getData()

◆ constructor() [2/2]

Qore::StringOutputStream::constructor ( string  encoding)

Creates the StringOutputStream.

Parameters
encodingthe encoding to tag the string data with
Note
raw binary data is written to the output stream, so it's up to the caller to ensure that only valid character data for the given encoding is written to the StringOutputStream object, otherwise a string with invalid character data will be returned by getData()

◆ getData()

string Qore::StringOutputStream::getData ( )

Returns the data written to the stream, clearing the internal buffer.

Returns
the data written to the StringOutputStream
Example:
StringOutputStream sos();
sos.write(<41>);
sos.write(<42>);
sos.write(<43>);
sos.getData(); # returns "ABC"
Exceptions
OUTPUT-STREAM-CLOSED-ERRORthe output stream has already been closed
STREAM-THREAD-ERRORthis exception is thrown if this method is called from any thread other than the thread that created the object

◆ getEncoding()

string Qore::StringOutputStream::getEncoding ( )

Returns the character encoding for the StringOutputStream.

Code Flags:
CONSTANT
Example:
StringOutputStream sos("latin1");
string encoding = sos.getEncoding();
Returns
the character encoding for the StringOutputStream
Note
raw binary data is written to the output stream, so it's up to the caller to ensure that only valid character data for the given encoding is written to the StringOutputStream object, otherwise a string with invalid character data will be returned by getData()

◆ hasData()

bool Qore::StringOutputStream::hasData ( )

Returns True if the stream already has data.

Returns
True if the stream already has data
Code Flags:
RET_VALUE_ONLY
Example:
bool has_data = sos.hasData();
Exceptions
OUTPUT-STREAM-CLOSED-ERRORthe output stream has already been closed
STREAM-THREAD-ERRORthis exception is thrown if this method is called from any thread other than the thread that created the object
Since
Qore 1.1

◆ write()

nothing Qore::StringOutputStream::write ( binary  data)
virtual

Writes bytes to the output stream.

Parameters
datathe data to write
Example:
StringOutputStream sos();
sos.write(<41>);
sos.write(<42>);
sos.write(<43>);
sos.getData(); # returns "ABC"
Exceptions
OUTPUT-STREAM-CLOSED-ERRORthe output stream has already been closed
STREAM-THREAD-ERRORthis exception is thrown if this method is called from any thread other than the thread that created the object

Implements Qore::OutputStream.