1.设计4个线程,其中两个线程每次对j增加1,另外两个线程对j每次减少1.写出程序. public class Question1 { private int j = 0; /** * @param args */ public static void main(String[] args) { Question1 q = new Question1(); Dec dec = q.new Dec(); Inc inc = q.new Inc(); for(int i=0; i<2;i++){ T