[medium snippets] #medium #designPattern #BuilderPattern

StreetMap.java

public class StreetMap {
  private final Point origin;
  private final Point destination;
  private final Color waterColor;
  private final Color landColor;
  private final Color highTrafficColor;
  private final Color mediumTrafficColor;
  private final Color lowTrafficColor;

  public static class Builder {
    private final Point origin;
    private final Point destination;

    private Color waterColor = Color.BLUE;
    private Color landColor = new Color(30, 30, 30);
    private Color highTrafficColor = Color.RED;
    private Color mediumTrafficColor = Color.YELLOW;
    private Color lowTrafficColor = Color.GREEN;
    
    public Builder(Point origin, Point destination) {
      this.origin = origin;
      this.destination = destination;
    }

    public Builder waterColor(Color color) {
      waterColor = color;
      return this;
    }

    public Builder landColor(Color color) {
      landColor = color;
      return this;
    }

    public Builder highTrafficColor(Color color) {
      highTrafficColor = color;
      return this;
    }

    public Builder mediumTrafficColor(Color color) {
      mediumTrafficColor = color;
      return this;
    }

    public Builder lowTrafficColor(Color color) {
      lowTrafficColor = color;
      return this;
    }

    public StreetMap build() {
      return new StreetMap(this);
    }
  }

  private StreetMap(Builder builder) {
    origin = builder.origin;
    destination = builder.destination;

    waterColor = builder.waterColor;
    landColor = builder.landColor;
    highTrafficColor = builder.highTrafficColor;
    mediumTrafficColor = builder.mediumTrafficColor;
    lowTrafficColor = builder.lowTrafficColor;
  }

  public static void main(String args[]) {
    Point origin = new Point(10, 10);
    Point destination = new Point(50, 50);
    StreetMap map = new StreetMap.Builder(origin, destination)
            .landColor(Color.GRAY)
            .waterColor(Color.BLUE.brighter())
            .build();
  }
}