Unable to draw in processing language when I integrated it with Eclipse - eclipse

Question

My setup method looks like below, I want to read one location file(City names with x and y co-ordinates) and then I am creating one hash-map of all cities so that I can draw(Will make points) them all on canvas
public void setup(){
background(0);
PFont title = createFont("Georgia", 16);
textFont(title);
text("This is a visualization of A* algorithm", 240, 20);
stroke(255);
line(0,25,800,25);
selectInput("Select a file for Locations:", "locFileSelected");
}
locFileSelected method(locFilePath is a global variable used):
public void locFileSelected(File locFile) {
locFilePath = locFile.toString();
this.readLocFileAndDraw();
}
Now control is transferred to readLocFileAndDraw (Each line in file has space separated 3 words, 1st is city name followed by x and y co-ordinates:
private void readLocFileAndDraw() {
try (Stream<String> lines = Files.lines(Paths.get(locFilePath))) {
for (String line : (Iterable<String>) lines::iterator){
// Last line in file is END, skip it
if(!line.equalsIgnoreCase("END")) {
List<Double> list = new ArrayList<Double>();
String[] arr= line.split(" ");
// adding coordinates into the list
list.add(Double.valueOf(arr[1]));
list.add(Double.valueOf(arr[2]));
// adding the list into the map with key as city name
locationsMap.put(arr[0], list);
}
}
} catch (IOException e) {
e.printStackTrace();
System.exit(0);
}
// Draw cities on map
// Draw graph of all cities
int w=1, h=1;
Set<Entry<String, List<Double>>> locationKeyEntries = locationsMap.entrySet();
for(Entry<String, List<Double>> currEntry: locationKeyEntries) {
String currCity = currEntry.getKey();
List<Double> currLocationList = currEntry.getValue();
int x = currLocationList.get(0).intValue();
int y = currLocationList.get(1).intValue();
stroke(255);
ellipse(x, y, w, h);
if(x>755)
x = x-(8*currCity.length());
if(y>755)
y=y-(8*currCity.length());
text(currCity, x,y);
}
return;
}
I tried to debug it, control is going to ellipse method but nothing is getting drew. Any idea? As far as I understand, I am missing passing reference of PApplet but I don't know how to do it...

Answer 1

Like you've mentioned, you really need to debug your program. Verifying that you're calling the ellipse() function is a great first step, but now you should be asking yourself more questions:
What is the value of x, y, w, and h being passed into the ellipse() function?
What is the value of currEntry in the for loop? What is the value of line when you're reading it in?
What are the fill, stroke, and background colors when you're drawing?
Note that I'm not asking you to tell me the answer to these questions. I'm pointing out these questions because they're what you should be asking yourself when you debug your program.
If you still can't figure it out, I really recommend breaking your problem down into smaller pieces and approaching each of those steps one at a time. For example, can you just show a single circle at a hard-coded point? Then work your way up from there. Can you read a single point in from a file and draw that to the screen? Then read two points. Work your way forward in small incremental steps, and post a MCVE if you get stuck. Good luck.