is my answer correct??? fix the code and provide the run screen

import java.util.Date;

public class Document {

private String[] authors;

private Data date;

int index;

public Document(){

authors =new String[50];

index=0;

}

public String[] getAuthors() {

return authors;

}

public void addAuther(String name);

{

authors[index]=name;

index++;

}

public Date getDate(){

return date;

}

public class Book extends Document{

private String title;

public String getTitle(){

return title;

}

public class Email extends Document{

private string subject;

private String []to;

public String[] getSubject() {

return subject;

}

public String[]getTo()

{return to;

}

}

public static void main (String[]args)

{

Book book=new Book();

book.setTitle("the");

book.setAuther("ghaida");

Email email=new Email();

email.setAuthor("gh");

email.setSubject("order");

email.setTo("Jeeee");

System.out.println("Subject:"+email.getSubject());

System.out.println("Dear"+email.to+","+"Thank you for your purchase on the book"+book.getTitle()+"by"+book.getAuthor()+". we are from" +email.getAuthor()+" Happy raeding!");}

Q2. Write a java program for the UML diagram given