JAVA visual interface calls Graphics class

Source code:
[Java]
Package hu;
 
Import java. applet .*;
Import java. awt .*;
 
Public class Boy extends Applet
{
Public void paint (Graphics g)
{
G. setColor (Color. red );
G. drawString ("I drink coffee while learning java", 5, 30 );
G. setColor (Color. blue );
G. drawString ("I learned very seriously", 5, 50 );
}

}

 

[Java]
Package hu;
 
Import java. applet .*;
Import java. awt .*;
 
Public class Boy extends Applet
{
/**
*
*/
// Private static final long serialVersionUID = 1L;
 
/**
*
*/
// Private static final long serialVersionUID =-5991863628806797002L;
 
Public void paint (Graphics g)
{
G. setColor (Color. red );
G. drawString ("I drink coffee while learning java", 5, 30 );
G. setColor (Color. blue );
G. drawString ("I learned very seriously", 5, 50 );
}

}

Result:

[Java]
// Private static final long serialVersionUID = 1L;
 
/**
*
*/
// Private static final long serialVersionUID =-5991863628806797002L;

What do these two codes mean?