Java matrix multiplication and rotation util

MatrixUtil.java

package net.luminu.core.api.shared.util;

import com.google.common.base.Preconditions;

/**
 * Methods for multiplying matrices and simple rotation methods.
 * See https://en.wikipedia.org/wiki/Rotation_matrix#In_three_dimensions for details on rotation.
 *
 * @author KennyTV
 */
public final class MatrixUtil {

    private MatrixUtil() {
    }

    /**
     * @param first  left matrix
     * @param second right matrix
     * @return multiplied matrix
     */
    public static double[][] multiply(final double[][] first, final double[][] second) {
        Preconditions.checkArgument(first[0].length == second.length);
        final double[][] result = new double[first.length][second[0].length];
        for (int i = 0; i < result.length; i++) {
            for (int j = 0; j < result[i].length; j++) {
                double multiplied = 0;
                for (int k = 0; k < second.length; k++) {
                    multiplied += first[i][k] * second[k][j];
                }
                result[i][j] = multiplied;
            }
        }
        return result;
    }

    /**
     * @param first  left matrix
     * @param second right nx1 (vertical) matrix
     * @return nx1 matrix
     */
    public static double[] multiply(final double[][] first, final double[] second) {
        Preconditions.checkArgument(first[0].length == second.length);
        final double[] result = new double[first.length];
        for (int i = 0; i < result.length; i++) {
            double multiplied = 0;
            for (int k = 0; k < second.length; k++) {
                multiplied += first[i][k] * second[k];
            }
            result[i] = multiplied;
        }
        return result;
    }

    /**
     * @param sin sin of the angle
     * @param cos cos of the angle
     * @return x rotation matrix (to be multiplied on the left)
     */
    public static double[][] getRotationMatrixX(final double sin, final double cos) {
        return new double[][]{{1, 0, 0}, {0, cos, -sin}, {0, sin, cos}};
    }

    public static double[][] getRotationMatrixX(final double angle) {
        return getRotationMatrixX(Math.sin(angle), Math.cos(angle));
    }

    /**
     * @param sin sin of the angle
     * @param cos cos of the angle
     * @return y rotation matrix (to be multiplied on the left)
     */
    public static double[][] getRotationMatrixY(final double sin, final double cos) {
        return new double[][]{{cos, 0, sin}, {0, 1, 0}, {-sin, 0, cos}};
    }

    public static double[][] getRotationMatrixY(final double angle) {
        return getRotationMatrixY(Math.sin(angle), Math.cos(angle));
    }

    /**
     * @param sin sin of the angle
     * @param cos cos of the angle
     * @return z rotation matrix (to be multiplied on the left)
     */
    public static double[][] getRotationMatrixZ(final double sin, final double cos) {
        return new double[][]{{cos, -sin, 0}, {sin, cos, 0}, {0, 0, 1}};
    }

    public static double[][] getRotationMatrixZ(final double angle) {
        return getRotationMatrixZ(Math.sin(angle), Math.cos(angle));
    }
}