debug11_3.java

北京大学出版社的

package questions.c11;
public class Debug11_3 {
   private double balance = 0.0;
   public void increaseBalance( double increase ) {
      synchronized (balance) {
         balance += increase;
      }
   }
   public void decreaseBalance( double decrease ) {
      synchronized (balance) {
         balance -= decrease;
      }
   }
   public static void main( String[] args ) {
      Debug11_3 x = new Debug11_3();
      x.increaseBalance( 100.75 );
      x.decreaseBalance( 50.50 );
   }
}