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/* A demonstration of writing and reading GNU Objective C objects to a file,
in human-readable text format.
Look at the file "textcoding.txt" after running this program to see the
text archive format.
*/
#include <objects/TextCoder.h>
#include <objects/StdioStream.h>
#include <objects/Set.h>
#include <objects/EltNodeCollector.h>
#include <objects/LinkedList.h>
#include <objects/LinkedListEltNode.h>
int main()
{
id set, ll;
id stream;
id coder;
const char *n;
/* Create a Set of int's
and a LinkedList of float's */
set = [[Set alloc] initWithType:@encode(int)];
ll = [[EltNodeCollector alloc] initWithType:@encode(float)
nodeCollector:[[LinkedList alloc] init]
nodeClass:[LinkedListEltNode class]];
/* Populate the Set and display it */
[set addElement:1234567];
[set addElement:2345678];
[set addElement:3456789];
[set addElement:4567891];
[set addElement:5678912];
[set printForDebugger];
/* Populate the LinkedList and display it */
[ll addElement:1.2f];
[ll addElement:(float)3.4];
[ll addElement:(float)5.6];
[ll addElement:(float)7.8];
[ll addElement:(float)9.0];
[ll printForDebugger];
/* Write them to a file */
stream = [[StdioStream alloc]
initWithFilename:"./textcoding.txt"
fmode:"w"];
coder = [[TextCoder alloc] initEncodingOnStream:stream];
[coder encodeObject:set withName:"Test Set"];
[coder encodeObject:ll withName:"Test EltNodeCollector LinkedList"];
/* Free the objects */
[coder free];
[set free];
[ll free];
/* Read them back in from the file */
/* First init the stream and coder */
stream = [[StdioStream alloc]
initWithFilename:"./textcoding.txt"
fmode:"r"];
coder = [[TextCoder alloc] initDecodingOnStream:stream];
/* Read in the Set */
[coder decodeObjectAt:&set withName:&n];
printf("got object named %s\n", n);
/* The name was malloc'ed by the Stream, free it */
(*objc_free)((void*)n);
/* Read in the LinkedList */
[coder decodeObjectAt:&ll withName:&n];
printf("got object named %s\n", n);
/* The name was malloc'ed by the Stream, free it */
(*objc_free)((void*)n);
/* Display what we read, to make sure it matches what we wrote */
[set printForDebugger];
[ll printForDebugger];
/* Free the objects */
[coder free];
[set free];
[ll free];
exit(0);
}
/* Some notes:
This program is a great example of how allocating and freeing
memory is very screwed up:
* The Stream allocates the name, we have to free it.
* The Coder free's its Stream when the Coder is free'd, but we
were the ones to create it.
These difficult and ad-hoc rules will be fixed in the future.
*/
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.