How to parse multiple for loops and generate new classes - parsing

Question

I need to parse a for loop containing variables and inner for loops. Each for loop further contains multiple variables and for loops.
Every for loop needs to be stored in a separate DTO class with its member variables and inner for loops as List variables. In below example, we have a main class A containing multiple for loops and inner for loops and member variables. All these need to be separated in separate DTO classes with other DTO class references as lists. I tried parsing this code using several possible ways but failed to mark inner for loops.
Class A{
public void a(){
int a1;
int a2;
for(int b=0; b < 10; b++) {
int b1;
int b2;
for(int c=0; c<10; c++){
int c1;
int c2;
for(int d=0; d<10; d++){
int d1;
int d2;
}
}
int b3;
int b4;
}
for(int e=0; e < 10; e++) {
int e1;
int e2;
int e3;
int e4;
}
int a3;
int a4;
}
Expected :
//class for main method
Class A_DTO{
int a1;
int a2;
List<B_DTO> b;
List<E_DTO> e;
int a3;
int a4;
}
//class for inner loop
Class B_DTO{
int b1;
int b2;
List<C_DTO> c;
int b3;
int b4;
}
//class for inner loop
Class C_DTO{
int c1;
int c2;
List<D_DTO> d;
}
//class for inner loop
Class D_DTO{
int d1;
int d2;
}
//class for inner loop
Class E_DTO{
int e1;
int e2;
int e3;
int e4;
}