Java.io.BufferedReader.read() Method

Description

The java.io.BufferedReader.read(char[] cbuf, int off, int len) method reads characters into specified character buffer.

Declaration

Following is the declaration for java.io.BufferedReader.read(charbuffer target) method

public int read(CharBuffer target) 

Parameters

• target − the character buffer to read characters into.

Return Value

The method returns a character as an integer. If the end of the stream has been reached the method returns -1.

Exception

• IOException − if an I/O error occurs

• NullPointerException − if the CharBuffer is null.

• ReadOnlyBufferException − if target is a read only.

Example

The following example shows the usage of java.io.BufferedReader.read(charbuffer target) method.

package com.tutorialspoint;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.CharBuffer;

public class BufferedReaderDemo {
   public static void main(String[] args) throws Exception {
      InputStream is = null; 
      InputStreamReader isr = null;
      BufferedReader br = null;

      try{
         // open input stream test.txt for reading purpose.
         is = new FileInputStream("c:/test.txt");
         
         // create new input stream reader
         isr = new InputStreamReader(is);
         
         // create new buffered reader
         br = new BufferedReader(isr);
      
         // creates and allocates CharBuffer
         CharBuffer cbuf = CharBuffer.allocate(is.available());
         
         // reads characters to CharBuffer
         br.read(cbuf);
         
         char[] chars = cbuf.array();
         // for each character in the buffer

         for (char c:chars)
         {

            // prints characters
            System.out.print(c);
         }
      }catch(Exception e){
         e.printStackTrace();
      }finally{
         // releases resources associated with the streams
         if(is!=null)
            is.close();
         if(isr!=null)
            isr.close();
         if(br!=null)
            br.close();
      }
   }
}

Assuming we have a text file c:/test.txt, which has the following content. This file will be used as an input for our example program:

ABCDEFGHIJKLMNOPQRSTUVWXYZ

Let us compile and run the above program, this will produce the following result:

ABCDEFGHIJKLMNOPQRSTUVWXYZ