Question

Is it necessary to create buffered reader while loop and all to read single line file? its also constant never changes

Answer 1

Here is how I would do it:

String txt = new Scanner(new File(path)).useDelimiter("\\Z").next();

This will read an entire file into the String.

Let me break that down for you:

String txt = // the resulting String is stored here
new Scanner( // Create a scanner to read the file
new File( "pathToFile" ) ) // pass a new file to the scanner to read
.useDelimiter("\\Z") // set the delimiter to the end of the file
.next(); // read the scanner until the next delimiter, 
         // in this case it is the end of the file.