Mixing byte and char input

Hi,
I have a setup where I wish to arbitarily read bytes or chars from the same underlying input stream, under jdk 1.3.x.
As far as I can see, InputStreamReader will always always over-read from the underlying stream (to the tune of 8k, if it can) and never replace the data it didn't use. This could be removing data that should have been read as binary data, and thus corrupting the stream.
Given that there's no way, it seems, of detecting the number of bytes per character for a given encoding, the only solution that I can think of is to provide an intermediate buffering stream that drip feeds the reader a conservative number of bytes. This obviously has profound efficiency implications if the reader has to re-fill() itself that often.
Has anyone else sucessfully dealt with this problem?

I'm still not
sure I understand the problem. Is it that the char
reader will keep reading past the chars removing the
binary data from what is left to be read and
preventing it from being read by a 'binary' reader?Yes - InputStreamReader, one of two ways to ensure that byte to char conversion is done properly pre-1.4, will use a fixed buffer size of 8192 bytes to read from the underlying stream.
It seems that you may need to read in everything as
binary data and delegate chars off to another Reader
as you come across them. Of course you will have to
know when the data should be interpreted as chars and
when it should not. Only acheivable insofar as the underlying mechanism will be told by clients what to read(i.e. readLine() / readBytes(), or something).
Some sort of home-rolled throttle between the underlying stream and the reader seems to be the only option, but this will be really clunky.
There will have to be some sort
of separator between the types. Am I understanding
that this will be used with several different
protocols?Yes, potentially a large number (this will, eventually, be a port of the Indy set of components for Delphi, http://www.nevrona.com/indy, FYI).

Similar Messages

Byte and char !!!

Hi!
What is the diference between an byte and char in Java! Could I use char instead of byte and reverse?
Thanks.

TYPE BYTE BITS SIGN RANGE
byte 1 8 SIGNED -128 to 127
char 2 16 UNSIGNED \u0000 to \uFFFF
Both the date types can be interchanged
Have a look at this
class UText
     public static void main(String[] args)
          byte c1;
          char c2= 'a';
          c1 = (byte) c2;
          c2 = (char) c1;
          System.out.println(c1 +" "+c2);
But It Leads to confusion while interchanging because of its SIGN. And the range of byte is very less.So its better to prefer char.

Newbie: 6020E (USB) slow performance with mixed digital and analog input

Hi,
I'm using a 6020E to do analog and digital input, and I'm getting very bad performance.
Please note that doing IO in Labview is new to me!
I have read the post about 6020E slow performance, and it says I should do buffered IO.
Can anybody point me to some DOC or SAMPLE that actually shows or explains how one should do this. I need to read several digital IO lines (which I can combine in one port-read), and several analog inputs.
Seeing how slow the reading on the 6020E is, I am amazed there is only one post that deals with this issue.
I would be satisfied to get the 6020E into some sort of continuous read mode so that whenever I need data, I get the latest reading right away.
thanks,
Peter D'Hoye

Hi Peter,
Your cannot do buffered digital I/O with your daqpad. It doesn't have that capability. You can only make direct software calls with digital read/write from/to your port. So your digital IO is completely software clocked and not hardware clocked. The example you are trying is only for specific Simultanuous sampling boards or now also for M-series boards that are able to do correlated DIO.
Use the Cont Acq&Graph Voltage-Int Clk.vi example for your analog measurements. (NI Example Finder) For your digital IO you can only use the examples like Read Dig Chan.vi, Read Dig Port,...
There are indeed some slow performance issues with single point I/O Operations, that is correct.
Check the explaination below:
DAQPads are offered for the Universal Serial Bus (USB) and the IEEE 1394 (also known as FireWire). Both of these standards use a high-speed serial communication protocol between the computer and the device with a bandwidth up to 12 MB/s for USB and 400 MB/s for FireWire.
During a single point operation, the DAQ device requires a complete set of configuration commands. This is done through serial communication (USB or FireWire), making the process slower than in a PCI-based board. The speed obtained for single point operation in a DAQPad is system dependent; this means that your computer processor, memory, bus speed, and other factors alter the speed at which you can do single-point operations with a DAQPad.
For example, on the DAQPad-6020E, timed non-buffered analog input operations are limited to about 50 Hz. At higher rates, the software may become unresponsive. On a FireWire device, you can expect stable operation around 3,000 Hz. But again, these figures are system dependent.
Regards.
JV
NI

Using byte or char array?

I am trying to use byte[] or char[] to read from a socket. I used byte[] and char[], both works fine. However, I know byte is 8 bits and char is 16 bits. Does it matter which one I used?
Thanks.

When you deal with streams of plain bytes you should use input/outputstreams, not readers or writers that are meant for character streams. The inputstream equivalent to BufferedReader is BufferedInputStream and there is a method for reading a full byte[] there...
But using a "bigger" data type than you need will not cause you big problems.

Oracle Best practices for changing Byte to Char on Varchar2 columns

Dear Team,
Application Team wanted to change Byte to Char on Varchar2 columns to accommodate Multi byte character on couple of production tables.
Wanted to know is it safe to have mixture of BYTE and CHAR semantics in the same table i have read on the couple of documents that It's good practice to avoid using a mixture of BYTE and CHAR semantics columns in the same table.
What happens if we have mixture of BYTE and CHAR semantics columns in the same table?
Do we need to gather stats & rebuild indexes on the table after these column changes .
Thanks in Advance !!!
SK

Application Team wanted to change Byte to Char on Varchar2 columns to accommodate Multi byte character on couple of production tables.
Wanted to know is it safe to have mixture of BYTE and CHAR semantics in the same table i have read on the couple of documents that It's good practice to avoid using a mixture of BYTE and CHAR semantics columns in the same table.
No change is needed to 'accommodate Multibyte characters'. That support has NOTHING to do with whether a column is specified using BYTE or CHAR.
In 11g the limit for a VARCHAR2 column is 4000 bytes, period. If you specify CHAR and try to insert 1001 characters that each take 4 bytes you will get an exception since that would require 4004 bytes and the limit is 4000 bytes.
In practice the use of CHAR is mostly a convenience to the developer when defining columns for multibyte characters. For example for a NAME column you might want to make sure Oracle will allocate room for 50 characters REGARDLESS of the actual length in bytes.
If you provide a name of 50 one byte characters then only 50 bytes will be used. Provide a name of 50 four byte characters and 200 bytes will be used.
So if that NAME column was defined using BYTE how would you know what length to use for the column? Fifty BYTES will seldom be long enough and 200 bytes SEEMS large since the business user wants a limit of FIFTY characters.
That is why such columns would typically use CHAR; so that the length (fifty) defined for the column matches the logical length of the number of characters.
What happens if we have mixture of BYTE and CHAR semantics columns in the same table?
Nothing happens - Oracle could care less.
Do we need to gather stats & rebuild indexes on the table after these column changes .
No - not if you by 'need' you mean simply because you made ONLY that change.
But that begs the question: if the table already exists, has data and has been in use without their being any problems then why bother changing things now?
In other words: if it ain't broke why try to fix it?
So back to your question of 'best practices'
Best practices is to set the length semantics at the database level when the database is first created and to then use that same setting (BYTE or CHAR) when you create new objects or make DDL changes.
Best practices is also to not fix things that aren't broken.
See the 'Length Semantics' section of the globalization support guide for more best practices
http://docs.oracle.com/cd/E11882_01/server.112/e10729/ch2charset.htm#i1006683

Hey guys ! I use logic pro ... not logic proX ... and i want to record my drums with 4 mics. I got a mixer with also 4 inputs ( Behringer Xenyx QX 1202USB ) But in my Logic i can't take the third input !?!? i can only choose 1 and 2 .... Please Help :)

hey guys ! I use logic pro ... not logic proX ... and i want to record my drums with 4 mics. I got a mixer with also 4 inputs ( Behringer Xenyx QX 1202USB ) But in my Logic i can't take the third input !?!? i can only choose 1 and 2 .... Please Help

Friedrich sp wrote:
Can you send me a mixer wich can do that, please ?
Who do you think I am? Santa Claus?
What you need is not a mixer, but an audio interface with at least 4 mic inputs. There is a lot of choice there, but you should indicate a budget. You can go from, say, € 300 to € thousands, if you want.
Roland UA 1010
Focusrite Scarlett 18i8
However, there are other options (like multi-out mixer plus multi in interface, or standalone mic preamps plus interface with 4 inputs, etc). I have little experience using these however so I really cannot say much about which one(s) to get. The two mentioned above both have four mic preamps, but they are by no means the only way to do it.
The cheapest solution I can think of is to get a second 1204USB, plug it in, and in OS X create an Aggregate device (=the two are being merged into 'one virtual' interface with two discrete stereo (= four discrete mono) inputs. Disadvantage: you keep the same (limited) soundquality of the 16 bits convertors. Getting any of the interfaces mentioned earlier will also mean you'll make the significant step up from 16 to 24 bits sound.

Form English Char ( Single Byte ) TO Double Byte ( Japanese Char )

Hello EveryOne !!!!
I need Help !!
I am new to Java ,.... I got assignment where i need to Check the String , if that string Contains Any Non Japanse Character ( a~z , A~Z , 0 -9 ) then this should be replaced with Double Byte ( Japanese Char )...
I am using Java 1.2 ..
Please guide me ...
thanks and regards
Maruti Chavan

hello ..
as you all asked Detail requirement here i an pasting C code where 'a' is passed as input character ..after process it is giving me Double Byte Japanese "A" .. i want this to be Done ..using this i am able to Convert APLHA-Numeric from singale byte to Doubel Byte ( Japanse ) ...
Same program i want to Java ... so pleas guide me ..
#include <stdio.h>
int main( int argc, char *argv[] )
char c[2];
char d[3];
strcpy( c, "a" ); // a is input char
d[0] = 0xa3;
d[1] = c[0] + 0x80;
printf( ":%s:\n", c ); // Orginal Single byte char
printf( ":%s:\n", d ); // Converted Double Byte ..
please ..
thax and regards
Maruti Chavan

Mixing XDCAM and HDV?? Outputting to SD DVD...

Hi
Earlier this year we shot a documentary on a Sony PDW-F350L HD XDCam (great camera, stunning footage - 35Mbps). Working in FCP has been fine.
We're doing a follow up and budget and logistics dictate that we sadly can't use 350s again (where we're going, carrying 2 Z1s for example is going to be a lot easier). We're also on a fairly steep learning curve (being relatively new to FCP, Compressor etc).
So I'm looking at options. We know that there are significant differences between say a Z1 and a 350 but from my research so far and from some relatively simple testing mixing Z1 footage (native) and 350 footage on FCP, at least editing on the timeline doesn't seem like it's going to present any problems (although thoughts on that welcome).
The issue seems to be outputting. In the first instance we'll be outputting to SD DVD. Yes, that old gem...
Searching round various forums, it seems this problem (HDV - SD) is fairly universal. Solutions seem to range from not working in Native HDV (suggestions vary on the format to ingest in - AIC etc); outputting to different formats first (eg DVCPro HD) and then to MPEG-2; outputting the timeline to tape (DV), re-importing; using some thing like a Matrox MXO to output and others...
We're aware of the shortcoming of HDV and the compressed nature of the format and our expectations, given our kit are realistic. I've even tried putting some PD150 footage on the timeline but that's just not going to cut it.
So, I've got to put a kit list together by next week and wondered if anyone had any thoughts on:
1) Mixing XDCAM and HDV on the timeline and any gotchas we should watch out for.
but more importantly
2) Any suggested routes I can look at to get some reasonable output with these two formats on the timeline - particularly HDV (don't think we'll have time to look at the Matrox route right now).
Many thanks in advance for any thoughts.
Cheers

Thanks Andy, Michael
That's good input. From an editing point of view we seem to be ok. Although, Michael, I take your point and that's a good suggestion.
The main problem is the workflow to create a decent SD DVD without the artefacts caused by compression/motion etc in HDV (and to some extent XDCAM).
Have read the prores whitepaper at
http://images.apple.com/finalcutstudio/resources/whitepapers/L342568A_ProResWP.pdf
And looked a little more into understanding GOP structures and it seems that ProRes will help in terms of editing.
The white paper seems to suggest that converting to ProRes, because it uses I frame–only encoding "Ensures consistent quality in every frame and no artifacts from complex motion. "
We'll try some tests but, does anyone know if this is true?
But it also seems that deinterlacing may solve some of the horrendous vertical edge rippling we're getting on the HDV footage when outputting to SD DVD - although if I'm honest I'm not sure how we achive that with our current setting.

Trying to understand the details of converting an int to a byte[] and back

I found the following code to convert ints into bytes and wanted to understand it better:
public static final byte[] intToByteArray(int value) {
return new byte[]{
(byte)(value >>> 24), (byte)(value >> 16 & 0xff), (byte)(value >> 8 & 0xff), (byte)(value & 0xff) };
}I understand that an int requires 4 bytes and that each byte allows for a power of 8. But, sadly, I can't figure out how to directly translate the code above? Can someone recommend a site that explains the following:
1. >>> and >>
2. Oxff.
3. Masks vs. casts.
thanks so much.

By the way, people often introduce this redundancy (as in your example above):
(byte)(i >> 8 & 0xFF)When this suffices:
(byte)(i >> 8)Since by [JLS 5.1.3|http://java.sun.com/docs/books/jls/third_edition/html/conversions.html#25363] :
A narrowing conversion of a signed integer to an integral type T simply discards all but the n lowest order bits, where n is the number of bits used to represent type T.Casting to a byte is merely keeping only the lower order 8 bits, and (anything & 0xFF) is simply clearing all but the lower order 8 bits. So it's redundant. Or I could just show you the more simple proof: try absolutely every value of int as an input and see if they ever differ:
   public static void main(String[] args) {
      for ( int i = Integer.MIN_VALUE;; i++ ) {
         if ( i % 100000000 == 0 ) {
            //report progress
            System.out.println("i=" + i);
         if ( (byte)(i >> 8 & 0xff) != (byte)(i >> 8) ) {
            System.out.println("ANOMOLY: " + i);
         if ( i == Integer.MAX_VALUE ) {
            break;
   }Needless to say, they don't ever differ. Where masking does matter is when you're widening (say from a byte to an int):
   public static void main(String[] args) {
      byte b = -1;
      int i = b;
      int j = b & 0xFF;
      System.out.println("i: " + i + " j: " + j);
   }That's because bytes are signed, and when you widen a signed negative integer to a wider integer, you get 1s in the higher bits, not 0s due to sign-extension. See [http://java.sun.com/docs/books/jls/third_edition/html/conversions.html#5.1.2]
Edited by: endasil on 3-Dec-2009 4:53 PM

NLS_LENGTH_SEMENTICS from BYTE TO CHAR

Hi,
For supporting multibyte character, we need to change NLS_LENGTH_SEMENTICS parameter from BYTE to CHAR. But this parameter setting will effect for new database tables created thereafter. To change the storage characteristics for existing database tables we explicitly executed Alter statements for database tables for columns having datatype as Varchar2 and Char.
Problem:
======
Since the number of database tables in PRODUCTION are very high and contains approx. 600 million of records spread over 400 database tables, we are not in a position to afford the time which will be spent in altering these database tables in PRODUCTION.
We ran the test by alter script in System Test environment and alteration of database tables covering 150 tables and 200 million of records was carried out in almost 16-20 hrs.
APPROACHES WE HAVE IN MIND
==========================
1. Alter all the table columns (We tried the same and taking too much time)
2. Export /Import with NLS_LENGTH_SEMENTICS set as CHAR(We discuss with our DBA about this approach and found that it will also take too much time and there is RISK of data inconsistency)
3. Drop the index of the table, run alter script for changing storage type BYTE to CHAR , and rebuild the index (this is also taking too much time).
All above approaches are very costly in terms of time, that we cannot afford.
If any one having better solution then please suggest.
thanks in advance
Syed

Hi
We are also facing a similar problem
We ran alter table scripts and now compiling the objects
and that is taking lot of time.
we have around 4000 invalids that by parallel recomp came down to 2000 but still these 2000 which are mostly packages .. are giving a hard time.
if anyone has faced/found a similar issue/solution pls post. or maildirectly to me.
Sunil Choudhary

Change NLS_LENGTH_SEMANTICS from BYTE to CHAR on Oracle 9i2 problem!

Hi,
I have created a new database on Oracle 9i 2, I did not find the correct pfile parameter for the NLS_LENGTH_SEMANTICS setting.
So have created a standart UTF8 database and now I am trying to change the standard NLS_LENGTH_SEMANTICS=BYTE to CHAR. When I execute the following command in SQL PLUS "ALTER SYSTEM SET NLS_LENGTH_SEMANTICS=CHAR SCOPE=BOTH"
The system is tells me that command is successfully executed.
But when I look at the NLS_DATABASE_PARAMETERS table I do not see any change for the NLS_LENGTH_SEMANTICS parameter.
I have also restarted the instance but still everything is the same as it was before.
Do you know what I am doing wrong?
Regards
RobH

Hi,
Yeah you are right, the nls_session_parameters "NLS_LENGTH_SEMANTICS" for the app user is set to CHAR.
This means that NLS_DATABASE_PARAMETERS is from the SYS or SYSTEM user view?
Thanks a lot
Regards
RobH

Cant record into to logic pro 9 using samson l1200 live mixer, System/Pref/Audio input tab says selected device has no input control

Hi Im new to this so bare with me..When I connect my Samson l1200 live usb mixer to my Imac 7,1 Intel duo core 3gb ram, osx10.6.8, via usb cable to record vocals/instruments, in System Pref/Audio/Output tab is set to mixer's UsbAudioCodec driver, (Im able to hear playback into headphones via the mixer, and hear the mic when spoken into it but cant record a track into Logic...System/Pref/Audio input tab says selected device has no input control, Ive set the input/output settings in Logic to UsbAudioCodec but still no good...Would it be either the way the mixer is set up? or is this mixer (Samson l1200) not compatible with my particular Imac? I hope I may be able to help as Im only a student trying to record my band thanks

I perfectly understand your problem.
First... just to make sure, in Logic's preferences /Audio make sure Universal Track Mode IS checked, it should be enabled. (I think it probably is just checking)
Second... if you record a track in a new Logic project and then go to the next track to record an overdubbed guitar part, are both parts recorded on the 2nd track?
What I'm asking is overdubbing working differently for two or three recorded tracks as opposed to overdubbing with an imported track.
What I think is happening is you have the main stereo output being recorded into Logic so if you playback an imported or recorded track from Logic while recording a 2nd track (overdub), both are going to be recorded on the 2nd track.
I took a look at the manual, here's the relevant sections.
34 – SEND – USB input send switch
The USB INPUT switch allows you to select one of
two stereo (or two channel) signal paths to feed the
USB output to send to the connected PC. When the
INPUT switch is in the up position, the USB signal will
feed from the MAIN left right mix. When the INPUT
switch is in the down position, the USB signal will
feed from the AUX 1 and AUX 2 buses which enables
you to create a unique mix to send to the PC.
35 – RETURN – USB return switch
The USB RETURN switch allows you to select one of
two stereo return paths to receive USB audio from
the connected PC. When the ASSIGN switch is in the
up position, the USB signal will return to the MAIN
mix bus. When the ASSIGN switch is in the down
position, the USB signal will return to the last pair
of stereo channels which enables you to playback a
recorded track in the MAIN mix, and you can use the
channels AUX sends to feed any of the AUX buses.
This will let you hear the USB playback tracks in the
monitor mixes.
36 – MONITOR – USB headphone enable switch
Press the USB MONITOR switch down if you want
to hear the signal from the USB return in the
headphones.

Using bytes or chars for String phonetic algorithm?

Hi all. I'm working on a phonetic algorithm, much like Soundex.
Basically the program receives a String, read it either char by char or by chunks of chars, and returns its phonetic version.
The question is which method is better work on this, treating each String "letter" as a char or as a byte?
For example, let's assume one of the rules is to remove every repeated character (e.g., "jagged" becomes "jaged"). Currently this is done as follows:
public final String removeRepeated(String s){
                char[] schar=s.toCharArray();
          StringBuffer sb =new StringBuffer();
          int lastIndex=s.length()-1;
          for(int i=0;i<lastIndex;i++){
               if(schar!=schar[i+1]){
                    sb.append(schar[++i]);//due to increment it wont work for 3+ repetions e.g. jaggged -> jagged
          sb.append(schar[lastIndex]);
          return sb.toString();
Would there be any improvement in this computation:public final String removeRepeated(String s){
          byte[] sbyte=s.getBytes();
          int lastIndex=s.length()-1;
          for(int i=0;i<lastIndex;i++){
               if(sbyte[i]==sbyte[i+1]){
                    sbyte[++i]=32; //the " " String
          return new String(sbyte).replace(" ","");
Well, in case there isn't much improvement from the short(16-bit) to the byte (8-bit) computation, I would very much appreciate if anyone could explain to me how a 32-bit/64-bit processor handles such kind of data so that it makes no difference to work with either short/byte in this case.

You may already know that getBytes() converts the string to a byte array according to the system default encoding, so the result can be different depending on which platform you're running the code on. If the encoding happens to be UTF-8, a single character can be converted to a sequence of up to four bytes. You can specify a single-byte encoding like ISO-8859-1 using the getBytes(String) method, but then you're limited to using characters that can be handled by that encoding. As long as the text contains only ASCII characters you can get away with treating bytes and characters as interchangeable, but it could turn around and bite you later.
Your purpose in using bytes is to make the program more efficient, but I don't think it's worth the effort. First, you'll be constantly converting between {color:#000080}byte{color}s and {color:#000080}char{color}s, which will wipe out much of your efficiency gain. Second, when you do comparisons and arithmetic on {color:#000080}byte{color}s, they tend to get promoted to {color:#000080}int{color}s, so you'll be constantly casting them back to {color:#000080}byte{color}s, but you have to watch for values changing as the JVM tries to preserve their signs.
In short, converting the text to bytes is not going to do anywhere near enough good to justify the extra work it entails. I recommend you leave the text in the form of {color:#000080}char{color}s and concentrate on minimizing the number of passes you make over it.

Mix FL, Mix RC, and recording q

hi folks
I've just switched over from the asio4all driver to the creative asio drivers to see if a sound-dropout in sonar7 would be alleviated.
Anyway, my question regards the numerous possible driver inputs for the X-Fi Platinum - the choices for inputs are:
Left Creative Windows Asio Rec
Right Creative Windows Asio Rec
Stereo Creative Windows Asio Rec?
Left Creative Mix FL Asio
Right Creative Mix FL Asio
Stereo Creative Mix FL Asio
Left Creative Mix RC Asio
Right Creative Mix RC Asio
etc etc etc
Lilke 25 driver inputs in Sonar.
What do the RC, the FL, and all the other acronmys stand for or do? I cannot find anything in the X-Fi docs that refer to these inputs. Obviously the left/right and stereo inputs are easy enough, but what are the others? Whats the difference between the Windows Rec and the Mix RC or Mix FL or Mix FC?
Thanks?

hi folks
I've just switched over from the asio4all driver to the creative asio drivers to see if a sound-dropout in sonar7 would be alleviated.
Anyway, my question regards the numerous possible driver inputs for the X-Fi Platinum - the choices for inputs are:
Left Creative Windows Asio Rec
Right Creative Windows Asio Rec
Stereo Creative Windows Asio Rec?
Left Creative Mix FL Asio
Right Creative Mix FL Asio
Stereo Creative Mix FL Asio
Left Creative Mix RC Asio
Right Creative Mix RC Asio
etc etc etc
Lilke 25 driver inputs in Sonar.
What do the RC, the FL, and all the other acronmys stand for or do? I cannot find anything in the X-Fi docs that refer to these inputs. Obviously the left/right and stereo inputs are easy enough, but what are the others? Whats the difference between the Windows Rec and the Mix RC or Mix FL or Mix FC?
Thanks?

Byte to Chars converter

Hi,
I'm looking for a converter from byte array to char for different encodings (ANSI, UTF-8 and UTF-16BE, UTF-16LE encodings).
I strongly believe there is a library/class that can do this.
Thanks in advance.
Lubos

Well the problem is that I have to count the number of bytes and look for a special characters (like Form Feed).
The only possibility I've found is to write my own parser..
I've tried the InputStreamReader and implement my own implementation of InputStream for counting the bytes, but it seems the method read(byte[]) is not called every time..

Mixing byte and char input

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