• Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Jeanne Boyarsky
  • Liutauras Vilda
  • Campbell Ritchie
  • Tim Cooke
  • Bear Bibeault
Sheriffs:
  • Paul Clapham
  • Junilu Lacar
  • Knute Snortum
Saloon Keepers:
  • Ron McLeod
  • Ganesh Patekar
  • Tim Moores
  • Pete Letkeman
  • Stephan van Hulst
Bartenders:
  • Carey Brown
  • Tim Holloway
  • Joe Ess

shift operators  RSS feed

 
Ranch Hand
Posts: 142
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi,

I am not able to understand shift operators. Can someone help me..
Though i know the basics of left and right shift operators, i encounter the problem when it comes to the calculations.
Pl go thru the following code..
class BitShift {
public static void main(String [] args) {
int x = 0x80000000;
System.out.println("Before shift x equals " + x);
x = x >> 4;
System.out.println("After shift x equals " + x);
}
}
I think in the exam we are not allowed to use the calculators..So how do i know x=-2147483648 and after shift x=-134217728
-sanjana
 
Ranch Hand
Posts: 504
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
You're not up to doing excessively laborious calculations on the exam, just stick to what's covered in K&B, they've done an awesome job about it. All you need to understand is how the shifting works in general, when the sign changes, and when the result remains the same. Also, make sure you're familiar with shifting by negative numbers and how implicit conversion applies to the operands. In your example, what's worth knowing is that 0x80000000 represents Integer.MIN_VALUE, you're right-shifting it by 4, so the sign stays negative, and the result will be Integer.MIN_VALUE/16.
 
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!