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Methods of Reader

The Reader class provides different methods that are implemented by its subclasses. Here are some of the commonly used methods:

  1. ready() - checks if the reader is ready to be read.
  2. read(char[] array) - reads the characters from the stream and stores in the specified array.
  3. read(char[] array, int start, int length) - reads the number of characters equal to length from the stream and stores in the specified array starting from the start.
  4. mark() - marks the position in the stream up to which data has been read.
  5. reset() - returns the control to the point in the stream where the mark is set.
  6. skip() - discards the specified number of characters from the stream.

Here is how we can implement Reader using the FileReader class. Suppose we have a file named input.txt with the following content.


\begin{lstlisting} This is a line of text inside the file. \end{lstlisting}

Let’s try to read this file using FileReader (a subclass of Reader).


\begin{lstlisting} import java.io.Reader; import java.io.FileReader; \par class ... ...e(); } \par catch( Exception e ) { e.getStackTrace(); } } } \end{lstlisting}

Output


\begin{lstlisting} Is there data in the stream ? true Data in the stream : This is a line of text inside the file . \end{lstlisting}

In the above example, we have created a reader using the FileReader class. The reader is linked with the file input.txt.