Now I'm learning design patterns, a teacher recommended online uml modeling tool (emphasis is free), is now recommended for everyone to
address the following tools are: https://www.processon.com
Click to register to use
example
I also learned that this is a textbook example of the design pattern, now enclosed for your reference:
Use processon drawing tips
To use the button above must first select a line or a drawing
each line has a start and end point and can change its style
in order to use direct drag to the left of the map ( "Notes" in uml general)
Right-click on the picture You can also create connections
in order to empty space to add text to the right in the figure can be found uml common that bar icon and drag to T line type
