Does File Input stream encode data

Hi,
When I retrieve a binary stream of an image from a database and print out all the bytes and then retrieve data with a FileInputStream from the same image stored as a file, and print the results, the 2 printouts are completely different. Can anyone explain why?
Thanz

However, the InputStreams do treat bytes as signed entities (-128 to +127 rather then 0 to 255). If you just print these out then you will get odd results which do not match the data you are expecting.
If you do the following
int tmp = b & 0xFF;
where b is a byte from your input then tmp will contain the unsigned value of that byte rather then the signed value.
matfud

Similar Messages

Re: File Input Streams FileNotFoundException

Hi,
I'm having problems with file input streams.
The program is supposed to read from an external file but when I run it in Sun ONE Studio 4 (update 1), it gives me a FileNotFoundException (The system cannot find the file specified). The file, class.dat, is in the same folder as the .java and .class files.
Anyway, so I run the program through MS-Prompt commands and there is no problem. It executes fine and gives the right output. Go figure.
Can anyone shed some light on what is going on? Anyone else with the same problem? Is there something I need to configure in SunStudio? Please help...
Thanks
The code is taken directly from Sams Java in 21 days.
// code
import java.io.*;
public class ReadBytes {
public static void main(String[] arguments) {
try {
FileInputStream file = new
FileInputStream("class.dat");
boolean eof = false;
int count = 0;
while (!eof) {
int input = file.read();
System.out.print(input + " ");
if (input == -1)
eof = true;
else
count++;
file.close();
System.out.println("\nBytes read: " + count);
} catch (IOException e) {
System.out.println("Error -- " + e.toString());

FileInputStream file = new FileInputStream("class.dat");Is this the line that is giving you the error message? Always, when trying to open a disk file, give the full path. This is because, FileNotFoundException is thrown only in cases when your file cannot be found by your program. But you say that the file exists.
Try giving your full path for the file...like:
FileInputStream file = new FileInputStream("C:/Program Files/class.dat");
//Ofcourse your path will be different. This is just an example!So try giving the full path and let me know.
Vijay :-)

How to get file input stream from the client machine by JSF Fileupload API?

Dear Friends,
How to get the file input stream from the client machine by JSF HtmlFileupload or fileupload API. At present, if i execute the file upload code in the client machine, it is able to get the local path of the file and looking for the file in server machine. So i am getting FileNotFoundException.
E.g., If a file is located at client machine at following location means "C:\Test\Test.txt",
uploadClass.getFileuploadComponent().getFilename().toString() returns "C:\Test\Test.txt". But it is looking for that file in server and throwing FileNotFoundException.
Please post your replies soon.
Thanks,
JP

Depends on which version of JSF you're using. If JSF 1.2, I wouldn't even bother trying to hack this into JSF itself unless you can use something like Seam 2 or richfaces.
http://docs.jboss.org/richfaces/latest_3_3_X/en/devguide/html/rich_fileUpload.html
http://docs.jboss.org/seam/2.2.1.CR3/reference/en-US/html/controls.html#d0e29259 (look for s:fileUpload)
But if I were you, a simple non-jsf form with a servlet works best for taking file uploads.
As for JSF 2.0, there are other ways of getting it done.
http://balusc.blogspot.com/2009/12/uploading-files-with-jsf-20-and-servlet.html

File Input Stream problem

i have a text file that i want to read to be my input into my database in db4o. i was looking through the websites. like http://java.sun.com/javase/6/docs/api/java/io/FileInputStream.html
and
http://www.java2s.com/Code/JavaAPI/java.io/FileInputStreamavailable.htm
there were different types too. like FileReader, FileInputStream. can anyone explain to me the differences between this two?
below is an example on how inside my text file is going to look like
Jack | China | 23
Helen | Holland | 34
Jenny | US | 34
Micheal | Brazil | 23
different attributes is separated by "|". i need to capture all this from a text file and store it in my db4o database. maybe someone could guide me on this? i am very new in java so forgive me if i am wrong. Thanks alot

ok. thanks alot. i will look into it
the "|" is because i want to separate different
attributes by using symbol
for example:
Name | Address | Age
Alex | Australia | 34
Jack | Malaysia | 32
Kate | Africa | 11
Holmes | California | 54
from there, this will be captured by the
BufferedReader (because this is use to capture text)
and read it and then stored inside the db4o. the
problem now is how can i capture the data and
automatic separate it as different field with this
"|" symbol
Message was edited by:
erickhHow about using Scanner:
Scanner inFile = new Scanner(new FileReader("a:\\file.txt"));

Using file input stream

hello,
i have the following problem.I have a file which consists of characters. I have to consider each character at a time for further manipulation, so in order to that i need to store it in an array..i have read the file using the following ..
public class fileinput
public static void main(String args[]) throws IOException
int size;
InputStream f = new FileInputStream("laser.txt");
System.out.println("total available bytes:" +(size=f.available()));
Now is it possible to store this file into a array ..when i use the following i'm getting an error coz "f.read()" returns an integer so it is incomaptible....
byte b[]=new byte[size];
for(int i=1;i<=size;i++)
b=f.read();
somebody plz help...

1. It is really inefficient to read 1 byte at a time. You might do better to read all the bytes you can get and then see what's in the byte[]
2. When using read(), here's what you want
int b;
while ( b = in.read() != -1) {
byte bb = (byte) b;

File Input Stream

Hello !
The FileInputStream has a constructor which uses FileDescriptor object as "FileInputStream(FileDescriptor fdobj)"
The practical use of FileDescriptor object is the FileInputStream and FileOutputStream to contain it.
Can someone help me how to make an elaborate use of it ? I want to use it in some manner in the following program .
God bless you.
NADEEM.
import java.io.* ;
public class CopyingText {
public static void main(String args[]) {
Thread t = new Thread();
try {
   System.out.println("Enter java CopyingText Source.txt Target.txt");
   FileInputStream a = new FileInputStream(args[0]);
   FileOutputStream b = new FileOutputStream(args[1],true);
   System.out.println("Source size: " + a.available());
   System.out.println(a.getFD());
    CopyingTxt rw = new CopyingTxt(a,b);
    rw.fileCopying();
//    rw.bytesAvailable();             Giving IOException: Bad file descriptor : Reason ?
} catch(Exception e) {
    System.out.println("Exception : main() :" + e );
    t.dumpStack();
class CopyingTxt   {
private int i , j ;
FileInputStream fa ;
FileOutputStream fb ;
CopyingTxt(FileInputStream a, FileOutputStream b) {
   fa = a ;
   fb = b ;
public int bytesAvailable() throws IOException {
   System.out.println(fa.getFD());
   System.out.println(fa.available());
    return fa.available() ;
public void fileCopying() throws IOException {
   do {
    i = fa.read();
    j++ ;
    if(i != -1) fb.write(i) ;
   } while(i != -1);                       //EOF condition -1 .
   System.out.println("Bytes read : " + (j-1) + " / " + fa.available());
   bytesAvailable();
   fa.close();
//    fa.finalize();
   fb.close();
//    fb.finalize();
}

Please don't crosspost. It cuts down on the effectiveness of responses, leads to people wasting their time answering what others have already answered, makes for difficult discussion, and is generally just annoying and bad form.

What's the fastest input stream reader?

Here's my candidate for the fastest stream reader. My interest and testing is with file input streams, but it's nice to support any stream.
     public static String readStream(InputStream is) throws IOException{
          int i, length = 0;
          StringBuffer s = null;
          char[] c = null;
          InputStreamReader isr = new InputStreamReader(is);
          while(length != -1){
               length = is.available();
               if(c == null) c = new char[length];
               isr.read(c, 0 , length);
               i = isr.read();
               if(i == -1){
                    if(s == null) return String.copyValueOf(c);
                    else break;
               }else{
                    if(s == null) s = new StringBuffer();
                    s.append(c, 0, length);
                    s.append((char)i);
          return s.toString();
     }

I do have a separate function that's optimized for file reading. I have tried the simpler implementation, and it is slower.
The reason I'm reading into a StringBuffer is that I have a DOM framework that allows you to load an xhtml document, do stuff, and then print out the result. I have Styles which allow you to merging a document with a style document and then in your project specific code, modify the resulting document. In one case, my style document is located on a remote machine and has the following:
<link rel="stylesheet" href="style.css" type="text/css" media="all"/>
I allow the Style class to override a "replaces" function that does string replacements and thus allows the non-xml compliant comment to be replaced by the appropriate URL prefix for the remote machine. I admit this probably isn't the best way to do it, since the comment makes the document invalid. I'd like to change to a better way, but I'd still like to keep the option of doing textual replaces on the input document before loading it into DOM. This may be a requirement since it is the convension that was previously used before we started using DOM.
As for bounded size, I figure the StringBuffer is going to be a lot smaller than the DOM representation anyway. And, neither should be that significantly large.

Server Socket does not read data input stream

Hi all,
I am very newbie to Java Network programming with sockets and multi-threading.
But I am obliged to develop a chat system written in Applets which can be placed on the website and used by visitors who come to my website.
In order to understand this, I have tested a basic web chat program I downloaded from the Internet which use sockets and multi-threadings. The program work fine, no bugs at all at both compilation and run time. I noticed that all three streams for Client side (i.e. first one is input stream used receiving data from User; the second one is socket input stream used for receiving data from Server socket, and the third is socket output stream used for writing data to server socket) were established. And the same, two socket streams (input & output) for Server side were also connected when running program giving right port number and IP address of the server.
The problem is both server and client sockets do not read data using the following stream classes:
1. DataStreamInput: I use input.readUTF() method
2. or BufferedReader: I use input.readLine() method
The example of the codes are below:
private BufferedReader input = null;
private PrintWriter output = null;
private Socket socket = null;
public void open() throws IOException
{ input = new BufferedReader(new
InputStreamReader(socket.getInputStream()));
System.out.println("Server socket input stream was created, and");
output = new PrintWriter(socket.getOutputStream());
System.out.println("Server socket output stream was created");
public void run()
{ System.out.println("Server Thread " + clientPort + " running.");
while (true)
{ try
System.out.println("Server is reading data from Client, wait...");
String fromClient = input.readLine();
System.out.println("Server received a message on " + clientPort + ".");
catch(IOException ioe)
{ System.out.println(clientPort + " ERROR reading: " + ioe.getMessage());
server.remove(clientPort);
stop();
The problem is at the line: String fromClient = input.readLine(); in the run() method? What is wrong with the codes above?
Note: I also try to use original codes which use readUTF() method in DataStreamInput class instead using readLine() in BufferedReader. Both methods dont read data from inputstream socket?
I very appreciate any help/advice from experienced developers.
Best regards

Hi,
Yes. The readLine() method hangs! After the test, the execuation of the program is stopped at the line of readLine() method; it does not pass it?
There is no problem with writing to Server socket. After the test, the program pass through flush() method. Here is the code for writing to sever socket within ChatClient (client side socket) class:
private BufferedReader input = null;
private PrintWriter           output = null;
public ChatClient(String serverName, int serverPort)
{ System.out.println("Establishing connection. Please wait ...");
try
{ socket = new Socket(serverName, serverPort);
System.out.println("Connected: " + socket);
start();
catch(UnknownHostException uhe)
{ System.out.println("Host unknown: " + uhe.getMessage()); }
catch(IOException ioe)
{ System.out.println("Unexpected exception: " + ioe.getMessage()); }
public void start() throws IOException
{ input   = new BufferedReader (new
                         InputStreamReader(System.in));
System.out.println("Client User input stream was created,");
output = new PrintWriter(socket.getOutputStream());
System.out.println("Client Socket output stream was established, and");
if (thread == null)
{ client = new ChatClientThread(this, socket);
thread = new Thread(this);
thread.start();
public void run()
     while (thread != null) {
     String fromUser;
          try{
               while((fromUser = input.readLine())!= null)
               System.out.println("Client wasreading a data from User, and");
output.println(fromUser);
     output.flush();
     System.out.println("Client has written a data to Server");
catch(IOException ioe)
{ System.out.println("Sending to server error: " + ioe.getMessage());
stop();
etc.
Here is a piece of codes for reading data from the Client Socket in the ChatServer Class (Server Side socket):
public void run()
{ System.out.println("Server Thread " + clientPort + " running.");
while (true)
{ try
{ //server.handle(clientPort, input.readLine());
System.out.println("Server is reading data from Client, wait...");
String fromUser = input.readLine();
//while((fromUser = input.readLine()) != null)
     System.out.println("Server received a message on " + clientPort + ".");
catch(IOException ioe)
{ System.out.println(clientPort + " ERROR reading: " + ioe.getMessage());
server.remove(clientPort);
stop();
etc. Please advice why the readLine() method hangs; does not read data from the input stream received from the CLIENT?

What does the Merge Data Stream processor do when there are multiple input streams to it from the same reader?

Hi,
I have a process with a reader of master data that outputs 5 records that feeds simultaneously into 3 different lookup and return processors.
Each lookup and return processor brings some data back from a detail table. There can be multiple details so I follow each lookup processor with a split records from array processor. Hence I end up with 3 'streams' of data. Stream 1 has 8 records, stream 2 has 5 records and stream 3 has 6 records.
I join all these streams to a Merge Data Streams processor.
I end up with 9 records so although the help for the Merge Data Streams processor says 'Merge Data Streams does not perform any transformation, matching, or merging of records' there is clearly some merging going on.
What is the behaviour of the merge data streams processor in this scenario?
I have added attributes and flags into each of the streams. How many records should I see and what values should the added attributes/flags have (some records show attributes/flags from all 3 streams whereas others show just those attributes/flags from one stream).
I have developed a test case simply to understand what the processor is doing but it's not obvious and furthermore it's probably unwise to develop EDQ processes where the processor behaviour is not documented and guaranteed to remain consistent. What I am trying to achieve is to bring all of a person's (the master data) various details (assignments, employers, etc.) together so we can check the data (some rules require data from multiple details).
Thanks, Nik

Cheers Mike - and for the explanation of the terms.
I think I understand now how it's supposed to work.
What I'm finding however is that when I set a flag to Y at the beginning of a path (that includes a lookup and return and then split records from array processor) that flag is showing no (i.e. an empty) value in SOME of the records shown in the subsequent MDS processor (it's fine the very last split processor before we get to the MDS but then again there are fewer records in that split processor than the MDS).
In my case there are obviously more records in the MDS processor than there were in the original reader (because the lookup and returns are configured to have unlimited maximum matches). As mentioned, the different paths return different numbers of records before being combined in the MDS. Say a reader has 5 records and path 1 returns 8 records in total including a path-specific flag (flag1, set to Y) but path 2 (that again adds its own path-specific flag (flag2, set to Y) returns just 5 records (since nothing was added from the lookups) are you saying that flag2 would show as 'Y' for all 8 records shown in the MDS?
Hopefully you would be able to see what I mean if you try to create a process like the one I've described (or I can upload a package).
Re. the purpose of the separate paths approach it is simply to allow the visualisation ('showing the working' as Neil puts it) of the different checks being carried out by the process.
This is considered one of the benefits of the tool over writing SQL queries (with outer joins, query criteria, etc.).
Also, as mentioned I was following an example that Neil put together for us to ensure that we are doing things in a 'proper' and supported way.
If we put all the lookups, etc. for all the checks into one datastream then it no longer becomes so understandable and the value of joining processors in a process over simply writing SQL becomes questionable; arguably the EDQ process in fact becomes less easy to understand than simply writing SQL.
Also, to go down this route I will need to revise the (what was previously substantially working until I revised it) processes that I have already developed.
Thanks, Nik

File input does not show up the result in OWL

Dear experts,
In the training material in chapter 3 step 9 there was a part talking about file input.
It works perfectly until I checked the WoC. There is no result showing up in the work center although in execution details there was a green dot and no errors.
Has anyone had similar issue? Where should I check to ensure that the mass data run works properly?
Many thanks
Cheers
Linh Hoang

Linh,
Latest update, which may help:
I did manage to get a file to work.
Here's the basic structure of my XML (i've renamed the elements):
<?xml version="1.0" encoding="UTF-8"?>
<MyCustomBusinessObjectUploadInputRequest>
<MessageHeader>
<CreationDateTime>2014-08-11T09:48:04.000Z</CreationDateTime>
<TestDataIndicator>false</TestDataIndicator>
<ReconciliationIndicator>false</ReconciliationIndicator>
</MessageHeader>
<List listCompleteTransmissionIndicator="true" actionCode="01" reconciliationPeriodCounterValue="123">

<MyCustomBusinessObject actionCode="01">
< ...Data Elements...>
</MyCustomBusinessObject>

</List>
</MyCustomBusinessObjectUploadInputRequest>
Here's what i'm currently working through now - if i have a single file with this structure in Unprocessed Files, and execute the run, it does work.
However, if i upload two files and run them both at the same time, it either takes a lot longer to process, or sometimes nothing happens. Both files work individually, but it seems very intermittent when processed together.

How do I return an input stream from a text file

Suppose there's a class with methods..
one of the methods is something like..
public int value() and has a return statement at the end obviously for returning an int value..
Another method reads a text file and creates an input stream..
Scanner data = new Scanner(new File(input.next()));
I want to return the data when I do a call to this method, but I'm not sure what the method heading would look like..

flounder wrote:
Are we supposed to magically know what those errors are? Do you think that copying and pasting the exact error messages and indicating the lines they occur on would be useful to us?Sorry about that..
I've replicated the same code below; and put the number of the line where the error is.
+cannot find symbol variable read     [line 21]+
+cannot find symbol variable read     [line 23]+
+cannot find symbol variable read     [line 29]+
+cannot find symbol variable read     [line 31]+
+cannot find symbol variable inputStream     [line 44]+
+calculate() in textInput cannot be applied to (java.util.Scanner)     [line 57]+
the reason I have the _______ for the createInputStream() method is because I'm not really sure what the heading type should be to return the input stream.
import java.io.*;
import java.util.*;
public class textInput
          public void requestFileName()
               Scanner input = new Scanner(System.in);
               System.out.print("Enter file name: ");
          public _______ createInputStream() throws FileNotFoundException
               Scanner input = new Scanner(System.in);
               Scanner read = new Scanner(new File(input.next()));
               return read;
          public void calculate() throws IOException
21           double max;
               double min;
23            int count = 0;
               double total = 0;
               if (read.hasNextDouble())
                    double temp = read.nextDouble();
29                 max = temp;
                    min = temp;
31                 count++
                    total += temp;
                    while (read.hasNextDouble())
                         double current = read.nextDouble();
                         count++;
                         min = Math.min(current, min);
                         max = Math.max(current, max);
                         total += current;
               System.out.println("Max of: " + max);
               System.out.println("Min of: " + min);
44            System.out.println("Average of " + total/count);
          public void close() throws IOException
               inputStream.close();
          public static void main(String[] args)
               textInput run = new textInput();
               try
57                 run.requestFileName();
                    run.createInputStream();
                    run.calculate();
                    run.close();
               catch(FileNotFoundException e)
                    System.out.println("File not found.");
                    System.exit(0);
               catch(IOException e)
                    System.out.prinln("File not found.");
                    System.exit(0);
}

Parse XML input stream (no .xml file)?

i have a java applet calling a web service that returns XML data as an input stream (char by char from SOAP) to this applet. if i append a all the chars to a string, is there some XML tool that will parse the string as if it were an XML document (like a getElement functions)?
the applet cannot write the data to a .xml file, and i don't want to mess around with .jarsigning. any ideas?
thanks,
jonathan

The XML parsers you are likely to be using support receiving input from a variety of sources besides files. For example you could parse XML from a String variable by passing a StringReader wrapping that String to the parser. Check the documentation for more details.

How to read a file as an input stream after it's posted in an HTML form ?

Hello,
I want to read client file after it's posted in an HTML form. But, I don't want to upload it to filesystem or database. I want to read posted file as an input stream. How can I do that ?
thanks in advance...

A couple of things. If you have a FILE field in your form, the enctype of the form must be multipart/form-data. Check this link
http://www.htmlhelp.com/reference/html40/forms/form.html
Also, when a file is uploaded you cannot use the regular methods to get at the name/value pairs or the file itself. You'll have to use a utility like MultiPartRequest or write your own based on the RFC for Multipart requests.
http://www.servlets.com/cos/javadoc/com/oreilly/servlet/MultipartRequest.html
You will need some temporary file system to store this and then delete it when you are done with it.
hth

Buffered Input stream - data corruption

Hi
I'm using the following code to transfer data to a file
BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(
        new StringBuffer(path).append(part.getFileName()).toString()));
    BufferedInputStream in = new BufferedInputStream(part.getInputStream());
    while (in.available() > 0) {
      out.write(in.read());
    out.close();
    in.close();It write the image and text files properly
But all the application based data like zip files,.doc files are getting corrupted
How do I solve it? What is the problem with the code?
Help pls

What a waste of buffers that code is.
We don't know how you might be corrupting the data
coming in because you haven't show us what that code
is like. All we see is part.getInputStream which is
hardly enough to make a diagnosis.OOps
private void writeAttachment(BodyPart part, String path) throws
      MessagingException,
      FileNotFoundException, IOException {
       //Make new dir
    new File(path).mkdirs();
    if (this.EnsileCall)
         this.log("Ensile writing <<" + part.getFileName() + ">> of size = " + part.getSize());
    // Write to file
    BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(
            new StringBuffer(path).append(part.getFileName()).toString()));
        BufferedInputStream in = new BufferedInputStream(part.getInputStream());
        while (in.available() > 0) {
          out.write(in.read());
    out.close();
    in.close();
part.getInputStream() Part corresponds to a message body part in a mail(The attachment)
I'm getting the mail attachment's input stream and writing it to a file.

Please prefix 'mp4:' to the stream name to record H264/AAC/HE-AAC encoded data at FMS using DVR...

I was able to modify the main.asc file in the application/livepkgr directory to include:
* DVRSetStreamInfo :
* This prototype was created to allow DVR recording funtionality to FLME to FMS
Client.prototype.DVRSetStreamInfo = function (info)
    var s = Stream.get( "mp4:" + info.streamname + ".f4v" ) ;
    if (s)
        if (info.append)
        s.record ("append") ;
        else
        s.record () ;
        s.play (info.streamname) ;
I get three status messages in the FLME encoding log:
Requested DVR command has been successfully issued to Primary FMS server for stream livestream1
Requested DVR command has been successfully issued to Primary FMS server for stream livestream2
Please prefix 'mp4:' to the stream name to record H264/AAC/HE-AAC encoded data at FMS using DVR feature
Now I have a few issues:
1. How to I fix the issue with the 3rd status message "Please prefix 'mp4:' to the stream name to record H264/AAC/HE-AAC encoded data at FMS using DVR feature" since the code above is prefixing the "mp4:" to the stream name.
2. In the applications/livepkgr/streams directory there is a file called "undefined.f4v" which is telling me the code above isn't passing the info.streamname variable.
3. Also, what do I need to do to playback this .f4v file. I've tried opening it with Adobe Media Player, but it doesn't recognize it.
I'm obviously using multi-bitrate streaming and that is working flawlessly. My goal is to record this livestream to later playback as an mp4 file.
Any ideas?
UPDATE:
I know on page 15 of the FMS 4.5.1 developers guide, "Configure DVR (HDS)" under "Publish a DVR stream", it states "To Publish a DVR stream from FLME, DO NOT check Record OR check DVR Auto Record. Publish the stream just as you publish any live stream. In the next section "Play DVR streams" is states that I can use SMP (Stobe Media Playback), which I am. So that brings up two more questions:
1. Why is my SMP Player not displaying the DVR funtionality (See image):
In my SMP configuration, my streamType is "LiveOrRecorded" - default. There is a streamType = "dvr", but will I lose live funtionality?
2. If I want to later on, package the stream into an mp4 file and play it back later for those who missed the live stream, what is the best approach for that?
Message was edited by: giostefani

Two things: You need to have "DVRCast" application on server-side i.e. "dvrcast_origin" for DVR recording to work and secondly for mp4 recording your stream name should be "mp4:<streamname>.mp4" while publishing.

Does File Input stream encode data

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