OOP

OO everything is an instance of something

public class Person {
  // Declaration of instance variables for 
  // the Person class is shown below in green.
  // They are also the attributes of the Person class.
  public String name;
  public int age;
  public int height;
  public String sex;
  // Methods of Person are given below
  public void drawPerson(Graphics g, int x, int y) {
    /* Write code to draw the person at position (x, y) in the graphics element g.
    */
  }
  public double grow(double increment) {
    /* Write code to grow the person
    This should increase the height of the Person
    */
  }
}

//filename: Person.java
import java.awt.*;
import java.applet.Applet;
public class Person {
  // Attributes of Person as shown below
  public String name;
  public int age;
  public int height = 80;
  public String sex;
  public void drawPerson (Graphics g, int x, int y) {
    // draws the person, anchored at (x,y)
    // draw head
    g.drawOval(x, y, 20, 30);
    g.drawArc(x+12, y+6, 6, 9, 200, 135);
    g.drawArc(x+3, y+6, 6, 9, 200,135);
    g.drawOval(x+7, y+20, 6, 5);
    //draw body
    g.drawLine(x+ 8, y + 30, x+ 8, y + height);
    g.drawLine(x+12, y + 30, x+12, y + height);
    //draw arms
    g.drawLine(x + 8, y + 30, x, y + 40);
    g.drawLine(x, y + 40, x + 8, y + 50);
    g.drawLine(x + 12, y + 30, x + 20, y + 40);
    g.drawLine(x + 20, y + 40, x + 12, y + 50);
    //draw feet
    g.fillRect(x, y + height, 10, 3);
    g.fillRect(x+11, y + height, 10, 3);
  }
}

//filename: PersonApplet.java
import java.awt.*;
import java.applet.Applet;
public class PersonApplet extends Applet {
  public Person joe; // Joe is an instance variable.
  public void init() {
    /* init() is called only once.
    This is where the applet is initialized.*/
    joe = new Person(); // Create a new object instance for Joe Hamilton.
  }
  public void paint ( Graphics g ) {
    joe.drawPerson(g, 20, 15); // Draw Joe on the applet.
  }
}

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