使用equals比较，如果不同，分别输出各自内容，怎么修改程序

Question

class Book{ private String title; private int price;  public Book(String title,int price){     //构造器  this.title=title;  this.price=price; } public String getTitle() {  return title; } public void setTitle(String title) {  this.title = title; } public int getPrice() {  return price; } public void setPrice(int price) {  this.price = price; }  public boolean equals(Object obj){  if(this==obj){     //比较地址是否相同   return true;  }  if(obj==null){     //判断要比较的对象是否为空   return false;  }  if(!(obj instanceof Book)){// 判断数据类型是否一样   return false;  }  Book book=(Book) obj;  //强转数据类型  if(this.title.equals(book.title)&&    this.price==book.price){   //自定义比较规则   return true;  }else {   return false;  }  } @Override public String toString() {  return "Book [title=" + title + ", price=" + price + "]"; }  } public class EqualsTest { public static void main(String[] args) {  Book book1=new Book("java",20);  Book book2=new Book("java",21);  System.out.println(book1.equals(book2));  book1.toString();  book2.toString();   } } 

Answer 1

public class EqualsTest {
 public static void main(String[] args) {
  Book book1=new Book("java",20);
  Book book2=new Book("java",21);
if(book1.equals(book2)){}
  System.out.println(book1.toString());

System.out.println( book2.toString());  }

 }
 
}