drawing line using some delay

[Dinesh Remje]

for(int i=0;i<firstSet.length;i++)
            {
                
                if(firstSet[i].y==secondSet[i].y)
                {
                    int j=i+1;
                    if(firstSet[i].x>=20 && firstSet[i].x<140)
                    {
                        g2d.drawLine(firstSet[i].x+40, firstSet[i].y + 40, firstSet[i].x+80, firstSet[i].y-10);
                        g2d.drawLine(firstSet[i].x+80, firstSet[i].y - 10, firstSet[i].x+600, firstSet[i].y-10);
                        g2d.drawLine(firstSet[i].x+600, firstSet[i].y-10, secondSet[j].x+40, secondSet[j].y + 40);
                    }
                    else if(firstSet[i].x>=140 && firstSet[i].x<210)
                    {
                        g2d.drawLine(firstSet[i].x+90,firstSet[i].y+60,secondSet[i].x+30,secondSet[i].y+60);
                    }
                    else
                    {
                        if(firstSet.length==5)
                            g2d.drawLine(firstSet[i].x+80,firstSet[i].y+60,secondSet[i-1].x,secondSet[i-1].y+60);
                        else
                            g2d.drawLine(firstSet[i].x+80,firstSet[i].y+60,secondSet[i].x-180,secondSet[i].y+60);
                    }
                }
          }

Now the above drawline i have written in paint method. Now i want to draw these lines using some delay(i mean i want to show some animation). Can anyone give me some examples of drawing lines using some delay or guide me to how to do it.