Java data structure and algorithm example: Fast computing the number of binary number 1 (Fast Bit counting) _java

/** 
 * Quickly calculates the number of 1 in a binary number (fast Bit counting) 
 * The idea of the algorithm is as follows: 
 * Each time you subtract the number from that number, the rightmost 1 is eliminated 
 * until the number is 0 
 * The number of intermediate loops is 1 of the number 
 * For example, given "10100", minus one after "10011", and "10000", which will eliminate the rightmost 1 
 * Sparse ones and dense ones were first Described by Peter Wegner in 
 * "a technique for counting ones in a Binary Computer", 
 * Communications of the ACM, Volume 3 (1960) Number 5, page 322 
 / 
package al; 
public class Countones {public 
 static void Main (string[] args) { 
  int i = 7; 
  Countones count = new Countones (); 
  System.out.println ("There are" + count.getcount (i) + "ones in I"); 
 } 
 /** 
  * @author * 
  @param i to be measured number 
  * @return binary representation of 1 of the number of * * Public 
 int getcount (int i) {   
  int n;
  for (n=0 i > 0; n++) { 
   i &= (i-1); 
  }   
  return n;   
 } 
}