file handling in java

Question

1.00/5 (1 vote)

See more:

when i open file rahul.txt so it shows characters which i stored not in form of bytes and second problem is that when i use FileInputStream to read file rahul.txt so it did not read .
package com.fileh;
import java .io.*;

public class Writedata {
public static void main(String args[])
{
try{
FileOutputStream fout= new FileOutputStream("rahul.txt");
String s="my name is rahul";
byte[] b =s.getBytes();
fout.write(b);
fout.close();
}
catch(IOException ioe)
{
}
}
}

Posted 14-Apr-15 9:42am

Member 11607403

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Sergey Alexandrovich Kryukov · Accepted Answer · 2015-04-14T10:12:00

Solution 1

No, it is saved in the form of bytes.

Probably you just did not realize it. It's possible that you don't understand what the byte is and how it is presented. If you think that the "byte" would look in the file read by some text editor, something as "0x2F", think again. Or, if you need that, format each byte as a string (2 or 4-character, as in this example) and output the resulting string. Right now, you can see those the bytes in some binary editor.

Also, you need to understand that your "may name is rahul" is represented in Unicode, and the result of String.getBytes is "a sequence of bytes using the platform's default charset, storing the result into a new byte arra":
http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#getBytes%28%29[^].

This is not very good due to this uncertainty. To be more certain, you would need to specify exact encoding. For further detail, please see this tutorial: https://docs.oracle.com/javase/tutorial/i18n/text/string.html[^].

For example, if you choose UTF-16, you will get two bytes per characters. With UTF-8, you get variable number of strings per characters, and full Unicode character repertoire can be covered. With ASCII, you will get exactly one byte per character, but ASCII works only for code points below 128 (less or equal to 127). As in your example all characters fit in the ASCII range, you will get 1 byte per character, same bytes for ASCII and UTF-8, but other characters not supported by ASCII, in case you use it, may be replaced with '?', which is unacceptable. So, always use UTFs for all general-purpose strings.

—SA

Posted 14-Apr-15 10:12am

Sergey Alexandrovich Kryukov

Updated 14-Apr-15 10:17am

v4

Comments

Member 11607403 15-Apr-15 1:58am

no if it stored in form of bytes so when i open rahul.txt so it shows as"it is may name is rahul"not shows any other form of byte.

Sergey Alexandrovich Kryukov 15-Apr-15 2:00am

Read the solution again; you did not understand anything.
—SA

Member 11607403 15-Apr-15 2:14am

i think i can not understand it .but i am beginner of java that's why can u help to explain it in easy way.

Sergey Alexandrovich Kryukov 15-Apr-15 2:31am

My guess was: you are also the beginner who voted 1 for the solution just because you did not understand it. Am I right?

In all cases, I'll gladly explain it better, but you have to tell me what was not "easy" and ask your follow-up questions.

—SA

Member 11607403 15-Apr-15 2:36am

ok sorry for that. fine but please explain this in easy way...

Sergey Alexandrovich Kryukov 15-Apr-15 2:55am

Sure, but in what part? Did you try to look at your file using some binary editor?
—SA

Member 11607403 15-Apr-15 3:27am

what i am saying when i creat and open rahul.txt in write mode thruogh
FileOutputStream fout= new FileOutputStream("rahul.txt");
and then i stored a string in "s"variable by
String s="my name is rahul";
then i call getbyte(); method for converting "my name is rahul"which stored in s variable in to the binary form.and stored in byte b[].by
byte[] b =s.getBytes();
then i write everything which converted in binary form in "rahul.txt" by fout refernce variable of object by
fout.write(b);
then i close it by
fout.close();

but when i search and open rahul.txt in notepad so it is showing as it is "my name is rahul"in "rahul.txt "which i write in but i want to see that words in binary form"my name is rahul" in "rahul.txt"which i actually stored.and if i can not see that so my question is why?

Sergey Alexandrovich Kryukov 15-Apr-15 3:34am

Of course. Those are bytes. If you don't understand it, you understand nothing. Text editor reads bytes.
Do you want to see, say "0x24" or the like? "0x24" is not byte, understand it, finally. In ASCII, this is 4 bytes. It's a string. Latin A can be represented as a byte equal to 65. But you are not supposed to see "65", you are supposed to see "A". "65" would be two bytes, equals to 54 and 53. What you wrote in your code is bytes.

In other words, text editor is the thing which can show the byte equal to 65 as "A". If you want to see byte values in hexadecimal or decimal form, use binary editor. Better yet, write your own one, perhaps then you can understand something.

Wait a minute? Aren't you ignoring something in my posts? I asked about voting... And I asked your if you used a binary editor...

—SA

Member 11607403 15-Apr-15 6:45am

ok i got it and thanxxx i used text editor thats why it shows every thing in character but it stored in binary formate

Sergey Alexandrovich Kryukov 15-Apr-15 8:59am

All right. Will you accept the answer formally now?
—SA

Member 11607403 15-Apr-15 9:27am

fine