new byte[]{0} in Objective C

Question

I'm trying to port the following Java code to Objective C.

myByteBuffer = new ByteArrayOutputStream(myCfA.length() + 1);
myByteBuffer.write(myCfA.getBytes());
myByteBuffer.write(new byte[]{0});
myWriter.write(myByteBuffer.toByteArray());
myWriter.flush();

It's relevant Objective-C code

NSInteger strLength = self.myCfA.length;
NSMutableString *response  = [NSMutableString stringWithCapacity:strLength];
[response appendString:self.myCfA];
[response appendString:@"0"];
NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSUTF8StringEncoding]];
NSInteger bytesCount = [self.outputStream write:[data bytes] maxLength:[data length]];

Is my approach of taking NSMutableString and then converting into NSData and getting bytes a correct approach? Also for new byte[]{0} I'm directly appending 0 as string. Please correct me if I'm going wrong. There is an issue here which I'm unable to trace out.

Thanks Sudheer

Augustine P A · Answer 1 · 2013-09-19T12:24:57.323

0

self.myCfA is a string and you can directly convert that to NSData. So the code given below will give you the same result.

NSData *data = [self.myCfA dataUsingEncoding:NSUTF8StringEncoding]
NSInteger bytesCount = [self.outputStream write:[data bytes] maxLength:[data length]];

Update: To append byte to the existing data.

NSMutableData *data = [NSMutableData dataWithData:[self.myCfA dataUsingEncoding:NSUTF8StringEncoding]];
[data appendBytes:[@"\0" UTF8String] length:1];
NSInteger bytesCount = [self.outputStream write:[data bytes] maxLength:[data length]];

edited Sep 19 '13 at 12:24

answered Sep 19 '13 at 11:47

Augustine P A

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ok but what about new byte[]{0} in ObjectiveC. How do we port it to give bytes or NSData? – Dantuluri Sep 19 '13 at 11:55
Why do you need the terminal null character? (But if you need it I think it would be `@"\0"`.) – Hot Licks Sep 19 '13 at 12:07
the line [data appendBytes:0x00 length:1]; is resulting in a crash :( – Dantuluri Sep 19 '13 at 12:20
I think the expected array should be terminated with null char. – Augustine P A Sep 19 '13 at 12:20
@AugustinePA - Shouldn't be any need to terminate with a null -- the NSData has an explicit length. – Hot Licks Sep 19 '13 at 18:02

new byte[]{0} in Objective C

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