* @param y1 Coordinates of first point of the line
* @param x2 Coordinates of second point of the line
* @param y2 Coordinates of second point of the line
*/
public void buildLabelAgents(int x1, int y1, int x2, int y2) {
LabelAgents l = new LabelAgents();
content.setLayout(null);
l.setVisible(true);
l.setBounds(x1, y1, Math.abs(x2-x1), Math.abs(y2-y1));
l.setLayout(null);
l.setBorder(null);
this.setLabelAgent(l);
content.add(l);
}