Triangle.java

class Triangle {
    /*@ specification Triangle {
        double a, b, c, h, S, p, alpha, beta, gamma, delta;
        double icr, ocr;
        p = a + b + c;
        a, b, gamma -> S {calcAreaSin};
        b, c, alpha -> S {calcAreaSin};
        a, c, beta -> S {calcAreaSin};
        a, b, c -> S {heron};
        a, b, gamma -> c {calcSide};
        a, c, beta -> b {calcSide};
        b, c, alpha -> a {calcSide};
        b, gamma -> h {calcHeight};
        c, beta -> h {calcHeight};
        b, h -> gamma {calcAngle};
        c, h -> beta {calcAngle};
        a, b, alpha -> beta {calcAngleSin};
        a, c, alpha -> gamma {calcAngleSin};
        b, c, beta -> gamma {calcAngleSin};
        b, a, beta -> alpha {calcAngleSin};
        c, a, gamma -> alpha{calcAngleSin};
        c, b, gamma -> beta {calcAngleSin};
        a, alpha, beta -> b{sinCalcSide};
        a, alpha, gamma -> c{sinCalcSide};
        b, beta, gamma -> c{sinCalcSide};
        b, beta, alpha -> a{sinCalcSide};
        c, gamma, alpha -> a{sinCalcSide};
        c, gamma, beta -> b{sinCalcSide};    
        a = (b * b - h * h)^(0.5) + (c * c - h * h)^(0.5);
        S = a * h / 2;
        icr = S / (p / 2);
        ocr = a * b * c / 4 / S;
    }@*/

    double calcHeight(double b, double gamma){
        return b*Math.cos(gamma);
    }

    double calcAngle(double a, double h){
        return Math.asin(h / b);
    }

    double calcAngleSin(double a, double b, double alpha){
        return Math.asin(Math.sin(alpha) * b/ a);
    }

    double calcAreaSin(double a, double b, double gamma){
        return a * b * Math.sin(gamma) / 2;
    }

    double heron(double a, double b, double c){
        double p = (a + b + c)/2;
        return Math.sqrt(p * (p - a) * (p - b) * (p - c));
    }

    double calcSide(double a, double b, double gamma){
        return Math.sqrt(a*a + b*b - 2*a*b*Math.cos(gamma));
    }

    double sinCalcSide(double a, double alpha, double beta){
        return a/Math.sin(alpha)*Math.sin(beta);
    }
}