Java/Language Basics/Shifting

Demonstrates short-circuiting behavior with logical operators

 
//: c03:ShortCircuit.java
// From "Thinking in Java, 3rd ed." (c) Bruce Eckel 2002
// www.BruceEckel.ru. See copyright notice in CopyRight.txt.
public class ShortCircuit {
  static boolean test1(int val) {
    System.out.println("test1(" + val + ")");
    System.out.println("result: " + (val < 1));
    return val < 1;
  }
  static boolean test2(int val) {
    System.out.println("test2(" + val + ")");
    System.out.println("result: " + (val < 2));
    return val < 2;
  }
  static boolean test3(int val) {
    System.out.println("test3(" + val + ")");
    System.out.println("result: " + (val < 3));
    return val < 3;
  }
  public static void main(String[] args) {
    if(test1(0) && test2(2) && test3(2))
      System.out.println("expression is true");
    else
      System.out.println("expression is false");
  }
} ///:~

Right shift

 
public class Main {
  public static void main(String[] args) {
    int m = 15 % 4;
    System.out.println("m = " + m);
    m = 29;
    System.out.println("m >> 2 = " + (m >> 2));
  }
}

Shift to the left three

 
public class Main {
  public static void main(String[] argv) throws Exception {
    byte c = - 10;
    System.out.println(c << 3); //
  }
}

Show some effects of shifting on ints and longs

 
/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.ru/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS""
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun"s Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun"s, and James Gosling"s,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */

/**
 //+
 * Show some effects of shifting on ints and longs
 //-
 * @author Ian F. Darwin, http://www.darwinsys.ru/
 * @version $Id: Shifting.java,v 1.3 2004/02/09 03:33:54 ian Exp $
 */
public class Shifting {
  public static void main(String[] argv) {
    //+
    System.out.println(" 2<<4 = " + (2<<4));
    System.out.println(" 2<<8 = " + (2<<8));
    System.out.println("2<<16 = " + (2<<16));
    System.out.println("2<<24 = " + (2<<24));
    System.out.println("2<<31 = " + (2<<31));
    System.out.println("2<<32 = " + (2<<32));
    // Now try those last two as longs
    System.out.println("2<<31 = " + ((long)2<<31));
    System.out.println("2<<32 = " + ((long)2<<32));
    //-
  }
}

Sign shift to the right

 
public class Main {
  public static void main(String[] argv) throws Exception {
    byte c = -10;
    System.out.println(c >> 1);
  }
}

Test of unsigned right shift.

 
//: c03:URShift.java
// From "Thinking in Java, 3rd ed." (c) Bruce Eckel 2002
// www.BruceEckel.ru. See copyright notice in CopyRight.txt.
public class URShift {
  public static void main(String[] args) {
    int i = -1;
    System.out.println(i >>>= 10);
    long l = -1;
    System.out.println(l >>>= 10);
    short s = -1;
    System.out.println(s >>>= 10);
    byte b = -1;
    System.out.println(b >>>= 10);
    b = -1;
    System.out.println(b>>>10);
  }
} ///:~

unSign shift to the right

 
public class Main {
  public static void main(String[] argv) throws Exception {
    byte c = -10;
    System.out.println(c >>> 1);
  }
}