how to make an GUI in java code example

Example 1: how to make a game in python

# Set up the screen
# Python 3.7.3 chromebook
# Turtle
import turtle

# Set up the screen
turtle.Screen()
wn = turtle.Screen()
wn.bgcolor("black")
wn.title("Ping Pong game by Aaryan")
wn.setup(width=800, height=600)
wn.tracer(0)

# Paddle A
paddle_a = turtle.Turtle()
paddle_a.speed(0)
paddle_a.color("white")
paddle_a.shape("square")
paddle_a.penup()
paddle_a.goto(-350, 0)
paddle_a.shapesize(stretch_wid = 5, stretch_len = 1)

# Paddle B
paddle_b = turtle.Turtle()
paddle_b.speed(0)
paddle_b.color("white")
paddle_b.shape("square")
paddle_b.penup()
paddle_b.goto(350, 0)
paddle_b.shapesize(stretch_wid = 5, stretch_len = 1)

paddle_aspeed = 20
paddle_bspeed = 20

# Ball
ball = turtle.Turtle()
ball.shape("circle")
ball.color("white")
ball.dy = 2
ball.dx = 2


# Function
def paddle_a_up():
    y = paddle_a.ycor()
    y += paddle_aspeed
    paddle_a.sety(y)

turtle.listen()
turtle.onkey(paddle_a_up, "Up")


def paddle_a_down():
    y = paddle_a.ycor()
    y -= paddle_aspeed
    paddle_a.sety(y)

turtle.listen()
turtle.onkey(paddle_a_down, "Down")

def paddle_b_up():
    y = paddle_b.ycor()
    y += paddle_bspeed
    paddle_b.sety(y)

turtle.listen()
turtle.onkey(paddle_b_up, "w")

def paddle_b_down():
    y = paddle_b.ycor()
    y -= paddle_bspeed
    paddle_b.sety(y)

turtle.listen()
turtle.onkey(paddle_b_down, "s")

# Main game loop
while True:
    wn.update()

Example 2: how to make a class in java

// Public creates avaliability to all classes/files
public class Object {
  // Instance of a variable per each class created
  public int a = 1;
  // Private restricts in local space (within these brackets)
  private int b = 5;
  
  // Defaults as public
  int c = 0;
  
  // Method Examples
  void setB(int B)
  {
  	b = B;
    // No return b/c 'void'
  }
  int getA()
  {
    return b;
    // Return b/c 'int' in front of method
  }
}