why？类初始化问题

class SingleTon {
  private static SingleTon singleTon = new SingleTon();
  public static int count1;
  public static int count2 = 0;

  private SingleTon() {
	count1++;
	count2++;
  }

  public static SingleTon getInstance() {
	return singleTon;
  }
}

public class Test {
  public static void main(String[] args) {
	SingleTon singleTon = SingleTon.getInstance();
	System.out.println("count1=" + singleTon.count1);//count1=1
	System.out.println("count2=" + singleTon.count2);//count2=0
  }
}

package com.test.classload;
class AAA {
  public static int count1;
  public static int count2 = 0;

  public AAA() {
	count1++;
	count2++;
  }
}

public class Test2 {
  public static void main(String[] args) {
	AAA aaa =  new AAA();
	System.out.println("count1=" + aaa.count1);//count1=1
	System.out.println("count2=" + aaa.count2);//count2=1
  }
}

why?

http://www.tuicool.com/articles/QZnENv 这篇解释看的不是很懂~~~