Java.io.FilterReader.read() Method

Description

The java.io.FilterReader.read(char[] cbuf, int off, int len) method reads character of length len into the array, starting at offset off.

Declaration

Following is the declaration for java.io.FilterReader.read(char[] cbuf, int off, int len) method:

public int read(char[] cbuf, int off, int len)

Parameters

• cbuf -- Destination buffer

• off -- Offset at which to start storing characters.

• len -- Number of characters to read

Return Value

This method returns the number of characters to read, or -1 if the end of the stream is reached.

Exception

• IOException -- If an I/O error occurs.

Example

The following example shows the usage of java.io.FilterReader.read(char[] cbuf, int off, int len) method.

package com.tutorialspoint;

import java.io.FilterReader;
import java.io.Reader;
import java.io.StringReader;

public class FilterReaderDemo {
   public static void main(String[] args) throws Exception {
      
      FilterReader fr = null;
      Reader r = null;
      char[] cbuf = new char[6];
      int i=0;
      
      try{
         // create new reader
         r = new StringReader("ABCDEF");
          
         // create new filter reader
         fr = new FilterReader(r) {
         };
         
         // read data of len 4, to the buffer
         i = fr.read(cbuf, 2, 4);
         System.out.println("No. of characters read: "+i);
         
         // read till the end of the char buffer
         for(char c:cbuf)
         {
            // checks for the empty character in buffer
            if((byte)c==0)
               c='-';
            
            // prints
            System.out.print(c);
         }
      }catch(Exception e){
         
         // if any I/O error occurs
         e.printStackTrace();
      }finally{
         
         // releases system resources associated with this stream
         if(r!=null)
            r.close();
         if(fr!=null)
            fr.close();
      }
   }
}

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

No. of characters read: 4
--ABCD