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javafile-handlingjava-iorandomaccessfile

RandomAccessFile writechar method writing NULto file and writeUTF writing ENQ , how to get ridoff those?

In java.io.RandomAccessFile , when the method writeChar() is used to write a char array in loop to a Text file as

RandomAccessFile txtfile = new RandomAccessFile("Hello.txt","rw");
char c[] = {'S','i','g','n','e','d'};
for(char k:c) txtfile.writeChar(k);

Gives a Result in Hello.txt as when opened in normal notepad

 S i g n e d

but , when opened with text Editor NotePad++ the Hello.txt is shown as

 [NUL]S[NUL]i[NUL]g[NUL]n[NUL]e[NUL]d

and when i used writeUTF() method to write a String to Hello.txt as

txtfile.writeUTF("hello");

it given result as a blank space in front and when opened in NotePad++ it is showing as

[ENQ]hello

How i can write or append a Normal Line to file with out Spaces(like [NUL] or [ENQ] ) as in this case ?

please post answer how to write any String to a file in RandomAccessFile in Java !

Thanks in Advance !

Solution

  • A char value in Java is two bytes. RandomAccessFile is meant to read and write binary data. It does not do any text transformations. When asked to write a character, it just writes the in-memory representation of that character to disk.

    Look at the documentation for the RandomAccessFile class:

    writeChar(int v)

    • Writes a char to the file as a two-byte value, high byte first.

    writeByte(int v)

    • Writes a byte to the file as a one-byte value.

    writeBytes(String s)

    • Writes the string to the file as a sequence of bytes.

    So use writeByte instead of writeChar to write a character to the file as a single ASCII byte that all editors should deal with in the same way. To write a String to the file as single-byte characters in one call, use the writeBytes method, which takes a String and writes it to the file as single-byte characters.

    If you only want to write text to a file, it's better to use a FileWriter or OutputStreamWriter class to do so. These classes write text taking character encoding into account. The former assumes a default character encoding. The latter allows you to specify the character encoding you want the class to use to convert text to bytes before writing to the file.