public Vector3f getRow(int i) {
        return getRow(i, null);
    }
Returns the specified row. The matrix is unaffected.

@param i the row index (0, 1, or 2)
@return a new Vector3f
@throws IllegalArgumentException if {@code i} isn't 0, 1, or 2
jme3-core/src/main/java/com/jme3/math/Matrix3f.java