The picture shows an example of using Graphviz to draw a graph for Traffic Information module. The arrows depict the objects's communication using Observer Pattern.
digraph TIComponent {
graph [ label = "\nTraffic Infomation's communication",
size = "11",
fontsize = 20,
fontcolor=blue4];
node [ //shape = box,
color = darkslateblue,
style = filled,
fillcolor = deepskyblue1];
edge [ decorate = false ]
rankdir=TB
subgraph cluster_TI {
style=filled;
color=lightblue1; l
abel="TI Kernel";
ranke=source
Tuner;
Receiver;
Cache;
Database; }
subgraph cluster_Device {
//node [shape = box]
style=filled;
color=khaki;
label="HAL";
Device; }
subgraph cluster_App {
style=filled;
color=plum1;
label="Application";
"Client 1";
"Client 2"; }
Tuner->"Client 1" [label="new station", labelfloat=false, color=darkgreen, fontcolor=darkgreen];
Tuner->Receiver [label="status of band scan",color=magenta, fontcolor=magenta];
Receiver->Cache [label="TrafficData", color=firebrick3, fontcolor=firebrick3];
Receiver->Tuner [label="search next station", color=gold2, fontcolor=gold2];
Cache->"Client 2" [label="message update", color=violet, fontcolor=violet];
Cache->"Client 1" [label="message update", color=violet, fontcolor=violet];
Database->Cache [arrowhead="dot", minlen=2];
Device->Receiver [arrowhead="dot", minlen=0];
Device->Tuner [headlabel="new station", labelfloat=true, color=darkgreen, minlen=2, labeldistance=2, fontcolor=darkgreen];
Tuner->Device [label="search next station", labelfloat=true, color=gold2, minlen=1, fontcolor=gold2];
}
To generate output as png from the dot, type
$ dot -Tpng -ooutput.png inputfile.dot
