How to Draw Line in Applet java code example

public static void drawLine(Graphics g, int i, int j, int k, int l, int i1)
    {
        if(i1 == 1)
        {
            g.drawLine(i, j, k, l);
            return;
        }
        int j1 = k;
        int k1 = l;
        int l1 = i;
        int i2 = j;
        if(i == k)
        {
            j1 = (k + i1) - 1;
            l1 = (i + i1) - 1;
        } else
        if(j == l)
        {
            k1 = (l + i1) - 1;
            i2 = (j + i1) - 1;
        } else
        {
            double d = (double)(l - j) / (double)(k - i);
            double d1 = Math.sqrt(1.0D / (1.0D + d * d));
            int j2 = (int)(d * d1 + (d <= 0.0D ? -0.5D : 0.5D));
            int k2 = (int)(d1 + 0.5D);
            j1 = k + j2;
            k1 = l + k2;
            l1 = i + j2;
            i2 = j + k2;
        }
        g.drawLine(i, j, k, l);
        g.drawLine(j1, k1, l1, i2);
        g.fillPolygon(new int[] {
            i, k, j1, l1
        }, new int[] {
            j, l, k1, i2
        }, 4);
    }