Java array inheritance

class A {
}
class B extends A {
}
public class Usage {
  public static void main(String[] args) {
    A[] aArr1 = new A[1];
    A[] aArr2 = new B[1];
    aArr1[0] = new B();

    B[] bArr1 = (B[]) aArr2;
    B[] bArr3 = new B[1];
    aArr1 = bArr3;
    B[] bArr2 = (B[]) aArr1; 
  }
}