convert c++ to java coe below#include toolsh#include iostreamusing EigenVectorXd;using EigenMatrixXd;using stdvector;using stdcout;using stdendl;ToolsTools Tools~Tools VectorXd ToolsCalculateRMSEconst

import org.ejml.simple.SimpleMatrix; import java.util.List;

public class Tools { public Tools() {}

public SimpleMatrix CalculateRMSE(List<SimpleMatrix> estimations, List<SimpleMatrix> ground_truth) {
    SimpleMatrix rmse = new SimpleMatrix(4, 1);
    rmse.set(0, 0, 0.0);
    rmse.set(1, 0, 0.0);
    rmse.set(2, 0, 0.0);
    rmse.set(3, 0, 0.0);

    if (estimations.size() != ground_truth.size() || estimations.size() == 0) {
        System.out.println("Invalid estimation or ground_truth data");
        return rmse;
    }

    for (int i = 0; i < estimations.size(); ++i) {
        SimpleMatrix residual = estimations.get(i).minus(ground_truth.get(i));

        // coefficient-wise multiplication
        residual.elementMult(residual);
        rmse = rmse.plus(residual);
    }

    // calculate the squared root of mean
    rmse = rmse.divide(estimations.size()).elementPower(0.5);

    return rmse;
}

public SimpleMatrix CalculateJacobian(SimpleMatrix x_state) {
    SimpleMatrix Hj = new SimpleMatrix(3, 4);

    // recover state parameters
    double px = x_state.get(0, 0);
    double py = x_state.get(1, 0);
    double vx = x_state.get(2, 0);
    double vy = x_state.get(3, 0);

    // pre-compute a set of terms to avoid repeated calculation
    double c1 = px*px + py*py;
    double c2 = Math.sqrt(c1);
    double c3 = c1*c2;

    // avoid division by zero
    if (Math.abs(c1) < 0.0001) {
        System.out.println("CalculateJacobian () - Error - Division by Zero");
        return Hj;
    }

    // compute the Jacobian matrix
    Hj.set(0, 0, px/c2);
    Hj.set(0, 1, py/c2);
    Hj.set(0, 2, 0);
    Hj.set(0, 3, 0);
    Hj.set(1, 0, -py/c1);
    Hj.set(1, 1, px/c1);
    Hj.set(1, 2, 0);
    Hj.set(1, 3, 0);
    Hj.set(2, 0, py*(vx*py - vy*px)/c3);
    Hj.set(2, 1, px*(px*vy - py*vx)/c3);
    Hj.set(2, 2, px/c2);
    Hj.set(2, 3, py/c2);

    return Hj;
}

}