How to get two dimensional Vector properties (count of inner vectors, element count in each inner vector) in Java?

Question

I have String Vector of Vectors in Java called data. I can access this vector elements:

(Vector) data.get(i)).get(j); 

How can i get count of inner vectors (i) and element count in each inner vector (j).

Answer 1

Use Vector.size() to get collection size. While this would solve your immediate problem:

int innerCount = ((Vector)data).size();
for (Object v: data) {
   int elementCount = ((Vector)v).size();
   ...
}

would suggest to use generics here to avoid casting:

int innerCount = data.size();
for (Vector v: data) {
   int elementCount = v.size();
   ...
}

Also ArrayLists are typically used now since the introduction of the Collections API in Java 2. See ArrayLists vs Vectors

Answer 2

Number of inner vectors:

((Vector)data).size();

Number of elements of each inner vector:

for(Vector v : (Vector)data) {
    int nrElemsInCurrentInner = v.size();
}