使用jpbc的程序需要很长时间

Question

This is a very simple program I have written that uses jpbc library. It compiles without any errors, but takes an unusually long time to show the output, or in fact it doesn't show the output at all. (Who in this era will have the patience to wait for nearly half an hour for such a tiny program?) I am using a system with i7 processor but still this is the case.

Could anyone tell what might be wrong with this code?

import it.unisa.dia.gas.jpbc.*;
import it.unisa.dia.gas.plaf.jpbc.pairing.PairingFactory;
import it.unisa.dia.gas.plaf.jpbc.pairing.parameters.*;
import it.unisa.dia.gas.jpbc.PairingParametersGenerator;
import it.unisa.dia.gas.jpbc.PairingParameters;
import it.unisa.dia.gas.plaf.jpbc.pairing.a1.TypeA1CurveGenerator;
public class PairingDemo {

    public static void main(String [] args){
        try{
            int rBits = 160;
            int qBits = 512;
            PairingParametersGenerator pg = new TypeA1CurveGenerator(rBits, qBits);
            PairingParameters params = pg.generate();
            Pairing pair = PairingFactory.getPairing("D:\\JPBCLib\\params\\curves\\a1.Properties");
            Field Zr = pair.getZr();
            int degree = pair.getDegree();
            System.out.println("Degree of the pairing : " + degree);
        }catch(Exception e){
            e.printStackTrace();
        }
    }
}

Answer 1

There are three issues that you're dealing with here

• Generating the pairing parameters takes some time, but this only has to be done once for a system that you're building. You should store the generated pairing parameter for later use.

• Since you're not using pg or params , you can remove that code. Instead you're reading precomputed parameters from a file.

• jPBC is a complete and pure Java implementation of PBC. It is fully portable and therefore quite slow. jPBC has an option of using a PBCWrapper library which is a wrapper around libpbc which would enable you to get the performance of the native library. I wasn't able to make it work on Windows, but Linux should not be an issue (make sure to check the JNI version or load your own).