Inner Class Doubts

[Micheal John]

class A {
  private static int counter;
  public static int getCounter(){return counter++;}
  private static int innerCounter;
  public static int getInnerCounter(){return innerCounter++;}
  private String name;
  A() {name = "A" + getCounter();}
  class B {
    private String name;
    B() {
      name = "B" + getInnerCounter();
      System.out.print(A.this.name + name); // 1
  }}
  public static void main(String[] args) {
    new A().new B();  // 2
    A a1 = new A();
    a1.new B();       // 3
    a1.new B();       // 4
}}

output:
Prints: A0B0A1B1A1B2

The output generated by the above pgm is very confusing. Can anyone explain it?

[Vinayagar Karpagam]

new A().new B(); // 2
A a1 = new A();
a1.new B(); // 3
a1.new B(); // 4

Output after line 2: A0B0 (name=A0, inname = B0, counter = 1, inCnt = 1)
Output after line 3: A0B0A1B1 (name = A1, inname = B1, counter = 2, inCnt = 1)
Before line 4: (name=A1, inname=B2, counter = 2, inCnt=2)
Output after line 4: A0B0A1B1A1B2 (name=A1, inname=B2, counter = 2, inCnt=3)

Hope this helps.