There is no easy way to connect Java and C++ although its very much possible using JNI (native methods connectivity to C/C++). Just don't try it. You gain absolutly NOTHING from reading a file in a totally different language and transferring data. Reading files in C++ is just as easy, if not easier. This example reads in 3 integers from the file in text format.
#include <fstream> // the file stream library
using namespace std;
ifstream input("test.txt"); // open the file
int a, b, c;
input >> a >> b >> c; // read in the variables
cout << "The three variables in the file were: " << a << ", " << b << ", " << c << endl;