Java PushbackInputStream (InputStream in) Constructor

Syntax

PushbackInputStream(InputStream in) constructor from PushbackInputStream has the following syntax.

public PushbackInputStream(InputStream in)

Example

In the following code shows how to use PushbackInputStream.PushbackInputStream(InputStream in) constructor.


//www .j  av  a 2  s . c  o  m
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.PushbackInputStream;

public class Main {
  public static void main(String args[]) throws IOException {
    byte buf[] = "==  = ".getBytes();
    PushbackInputStream f = new PushbackInputStream(new ByteArrayInputStream(buf));
    int c;
    while ((c = f.read()) != -1) {
      switch (c) {
      case '=':
        c = f.read();
        if (c == '=')
          System.out.print(".eq.");
        else {
          System.out.print("=");
          f.unread(c);
        }
        break;
      default:
        System.out.print((char) c);
        break;
      }
    }
  }
}

The code above generates the following result.