Java - BufferedReader skip(long n) method

Description

The Java BufferedReader skip(long n) method skips over a specified number of characters in the stream. It moves the reader forward by n characters, discarding the skipped characters. It returns the actual number of characters skipped, which might be less than n if the end of the stream is reached before skipping n characters.

Declaration

Following is the declaration for java.io.BufferedReader.skip(long n) method.

public long skip(long n)

Parameters

n − n number of characters to be skipped.

Return Value

This method returns actual number of characters skipped.

Exception

• IOException − If some I/O error occurs.

• IllegalArgumentException − If n is negative.

Example - Using a BufferedReader skip(long n) method

The following example shows the usage of BufferedReader skip(long n) method.

BufferedReaderDemo.java

package com.tutorialspoint;

import java.io.BufferedReader;
import java.io.StringReader;

public class BufferedReaderDemo {
   public static void main(String[] args) throws Exception {
      String s ="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
      StringReader sr = null; 
      BufferedReader br = null;

      try {
         // create and assign a new string reader
         sr = new StringReader(s);
         
         // create  new buffered reader
         br = new BufferedReader(sr);

         // reads and prints BufferedReader
         int value = 0;
         
         while((value = br.read()) != -1) {
         
            // skips a character
            br.skip(1);
            System.out.print((char)value);
         }
         
      } catch (Exception e) {
         // exception occurred.
         e.printStackTrace();
      } finally {
         // releases any system resources associated with the stream
         if(sr!=null)
            sr.close();
         if(br!=null)
            br.close();
      }
   }
}

Output

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

ACEGIKMOQSUWY

Example - Skipping Characters and Reading the Remaining Input

The following example shows the usage of BufferedReader skip(long n) method.

BufferedReaderDemo.java

package com.tutorialspoint;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.StringReader;

public class BufferedReaderDemo {
   public static void main(String[] args) {
      String input = "Hello, World! This is a BufferedReader skip() example.";

      // Initialize BufferedReader with a StringReader
      try (BufferedReader reader = new BufferedReader(new StringReader(input))) {
         // Skip the first 7 characters
         long skipped = reader.skip(7);
         System.out.println("Skipped characters: " + skipped);

         // Read and print the remaining input
         String remaining = reader.readLine();
         System.out.println("Remaining input: " + remaining);
      } catch (IOException e) {
         System.err.println("An error occurred: " + e.getMessage());
      }
   }
}

Output

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

Skipped characters: 7
Remaining input: World! This is a BufferedReader skip() example.

Explanation

• The BufferedReader is initialized with a string containing a sentence.

• The skip(7) method skips the first 7 characters in the stream ("Hello, ").

• The program prints the number of characters actually skipped.

• The readLine() method reads and prints the remaining input.

Example - Using skip() to Move Past Unwanted Characters

The following example shows the usage of BufferedReader skip(long n) method.

BufferedReaderDemo.java

package com.tutorialspoint;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.StringReader;

public class BufferedReaderDemo {
   public static void main(String[] args) {
      String input = "12345-ABCDE-67890";

      // Initialize BufferedReader with a StringReader
      try (BufferedReader reader = new BufferedReader(new StringReader(input))) {
         // Read the first 5 characters
         char[] firstPart = new char[5];
         reader.read(firstPart, 0, 5);
         System.out.println("First part: " + new String(firstPart));

         // Skip the next 6 characters (the hyphen and "ABCDE")
         long skipped = reader.skip(6);
         System.out.println("Skipped characters: " + skipped);

         // Read the remaining input
         String remaining = reader.readLine();
         System.out.println("Remaining part: " + remaining);
      } catch (IOException e) {
         System.err.println("An error occurred: " + e.getMessage());
      }
   }
}

Output

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

First part: 12345
Skipped characters: 6
Remaining part: -67890

Explanation

• The BufferedReader is initialized with a string containing groups of characters separated by hyphens.

• The first 5 characters ("12345") are read using read(char[], int, int).

• The skip(6) method skips the next 6 characters (the hyphen and "ABCDE").

• The readLine() method is used to read the remaining part of the string ("67890").

Key Points About skip()

• Skips Characters− The method skips over the specified number of characters (n) in the stream.

• Return Value− It returns the actual number of characters skipped, which may be less than n if the end of the stream is reached.

• Efficient Navigation− It is useful for navigating over unwanted parts of the input without processing them.

These examples show how the skip() method can be used to efficiently move through parts of an input stream.