How to draw a directed arrow line in Java?

Question

I want to draw a directed arrow line through Java.

At present, I am using java.awt.Line2D.Double class to draw a line

g2.setStroke(new B         


        

Answer 1

This is my approach, absolute Math only:

/**
 * Draw an arrow line between two points.
 * @param g the graphics component.
 * @param x1 x-position of first point.
 * @param y1 y-position of first point.
 * @param x2 x-position of second point.
 * @param y2 y-position of second point.
 * @param d  the width of the arrow.
 * @param h  the height of the arrow.
 */
private void drawArrowLine(Graphics g, int x1, int y1, int x2, int y2, int d, int h) {
    int dx = x2 - x1, dy = y2 - y1;
    double D = Math.sqrt(dx*dx + dy*dy);
    double xm = D - d, xn = xm, ym = h, yn = -h, x;
    double sin = dy / D, cos = dx / D;

    x = xm*cos - ym*sin + x1;
    ym = xm*sin + ym*cos + y1;
    xm = x;

    x = xn*cos - yn*sin + x1;
    yn = xn*sin + yn*cos + y1;
    xn = x;

    int[] xpoints = {x2, (int) xm, (int) xn};
    int[] ypoints = {y2, (int) ym, (int) yn};

    g.drawLine(x1, y1, x2, y2);
    g.fillPolygon(xpoints, ypoints, 3);
}