Looping through an array with g.drawString()

Question

Here I have some code(shortened to show the most important parts)

private Map<String, Color> hashMap = new HashMap<String, Color>();
for (int u = 0; u < people.size(); u++) {
    if (people.get(u) instanceof Boy) {
        list[u]="B";
        hashMap.put(list[u], Color.red);
        System.out.print("B");
    } else if (people.get(u) instanceof Girl) {
        System.out.print("G");
        list[e] = "G";
        hashMap.put(list[u], Color.green);
    }

}

public void paintComponent(Graphics g){
    super.paintComponent(g);
    g.drawString(list, 10, 10)
    // I would like to color each value according to its key in the hashMap list looping through my array
}

I would like my g.drawString() to loop through my array called list which contains [B,G,G,B,B,B,B,G] and color each value according to its colour based on my hashMap and return this array coloured..

so my hashMap["G" = color.green, "B"=color.red]

I tried this :

public void paint(Graphics g){

    g.setColor(hashMap.get("B") 
    g.setColor(hashMap.get("G")
    g.drawString(list, 10, 10)
}

but this seems to colour the whole text green or red could some one explain how to loop the the array called list and use g.drawString to colour each value accordingly?

EDIT

 for (int u = 0; u < people.size(); u++) { 
 Person p = people.get(u); 
list[u] = p.getGenderAsChar(); colorMap.put(r.getGenderAsChar(),r.getColorRepresentation() }


public void paintComponent(Graphics g){
super.paintComponent(g);
for (int c = 0; c< list.length; c++)
Person p = people.get(u);
 g.setColor(hashMap.getColorRepresentation);
g.drawString(list[c], 10 + c*10, 20);

}

Answer 1

First for your actual question: just check out the JavaDoc for drawString(). That method expects a single String.

So you should rather write some code like

for (i=0; i < list.length(); i++) {
  g.setColor(hashMap.get(list[i]));
  g.drawString(list[i], 10 + i*10, 10);
}

or something alike.

In other words: you can't pass the whole array into that call. You have to call it once for each string you want to display; and of course, you then have to account for the horizontal spacing.

Alternatively, you could simply concatenate your chars into a single string BBBG... but then you loose the ability to change the color for the different chars.

But then beyond that.

Your abstractions are wrong - you are not doing good "OO" here.

OO is not about "lets ask some object about its state, or in your case, its type" to then make a decision based on that. Instead, you tell the object to do the right thing.

Meaning; code like

if (people.get(u) instanceof Boy) {
  list[u]="B";
  hashMap.put(list[u], Color.red);
}

should rather be something like

Person p = people.get(u);
list[u] = p.getGenderAsChar(); // to return either 'B' or 'G'

The idea behind that: you have an (abstract) base class Person; and then you create specific sub classes, Boy extends Person and Girl extends Person.

And those to classes both implement that method getGenderAsChar() and return different values.

Similar for

hashMap.put(list[u], Color.green);

You see, your list contains only B or G strings anyway. So you just keep putting (B, red) or (G, green) into that Map. Doesn't make any sense.

Instead, you could again have an abstract base method getColorRepresentation() and the Boy class returns Color.red; and Girls return Color.green.