Java class files(under construction)

Build

• Install swig and Java.

Windows

• set SWIG to the path to swig in make_wrap.bat
• set JAVA_DIR to the path to java in set-java-path.bat.
• Use the follogin commands:

  > cd java
  > make_wrap.bat

• bin/bn254_if_wrap.dll is a dll for java.

Linux

• set JAVA_INC to the path to Java in Makefile

‍make test

• bin/libbn254_if_wrap.so is a shared library for java.

API and Class

Setup

• At first, call these functions.

  > System.loadLibrary("bn254_if_wrap");
  > BN254.SystemInit();

  class Mpz

• a wrapped class of mpz_class of GMP.
• Mpz(int), Mpz(String)
• void set(int x)
  • Set x to this.
• void set(String x)
  • Set x to this.
• void add(Mpz x)
  • Set (this + x) to this.
• void sub(Mpz x)
  • Set (this - x) to this.
• void mul(Mpz x)
  • Set (this * x) to this.
• void mod(Mpz x)
  • Set (this % x) to this.

class Fp, Fp2, Fp12

• a wrapped class of bn::Fp, bn::Fp2, bn::Fp12.

common method

• Fp(int), Fp(String)
• void set(int x)
  • Set x to this.
• void set(String x)
  • Set x to this.
  • The format of Fp is "123", "0xabc"
  • The format of Fp2 is "[a,b]" ; a, b are the format of Fp
  • The format of Fp12 is "[[[a0,b0],[a1,b1],[a2,b2]], [[a3,b3],[a4,b4],[a5,b5]]]"
• void add(Fp x)
  • Set (this + x) to this.
• void sub(Fp x)
  • Set (this - x) to this.
• void mul(Fp x)
  • Set (this * x) to this.
• void power(Mpz x)
  • Set (this ^ x) to this.

Fp2

• Fp2(int a, int b)
  • Set (a, b) to this.
• Fp2(Fp a, Fp b)
  • Set (a, b) to this.
• Fp2(String a, String b)
  • Set (a, b) to this.
• Fp getA()
  • Return the reference to a where this = (a, b).
• Fp getB()
  • Return the reference to b where this = (a, b).

Fp12

• pairing(Ec2 ec2, Ec1 ec1)
  • Set opt_ate_pairing(ec2, ec1) to this.

Ec1, Ec2

• a wrapped class of bn::Ec1 and bn::Ec2.
• Ec1(Fp x, Fp y)
  • Set (x, y, 1) to this.
• Ec1(Fp x, Fp y, Fp z)
  • Set (x:y:z) to this.
• Ec1(String x)
  • Set x to this.
  • The format of Ec1 is "x_y" or "0" ; x, y are the format of Fp. "0" is the infinity point.
  • The format of Ec2 is "x_y" or "0" ; x, y are the format of Fp2.
• Boolean isValid()
  • Is (x:y:z) on the curve?
• Boolean isZero()
  • Is this equal to the infinity point?
• void clear()
  • set this to the infinity point.
• dbl()
  • set (this * 2) to this.
• neg()
  • Set (-this) to this.
• add(Ec1 x)
  • Set (this + x) to this.
• sub(Ec1 x)
  • Set (this - x) to this.
• mul(Mpz& x)
  • Set (this * x) to this.
• Fp getX()
  • Return the value of x.
• Fp getY()
  • Return the value of y.
• Fp getZ()
  • Return the value of z.