content: package com.app;
  
  import java.io.Serializable;
  import java.util.Objects;
  import javax.persistence.Entity;
  import javax.persistence.Id;
  
  @Entity
  public class IdManBook implements Serializable {
  
      private static final long serialVersionUID = 1L;
  
      @Id
      private Long id;
  
      private String title;
      private String isbn;
  
      public Long getId() {
          return id;
      }
  
      public void setId(Long id) {
          this.id = id;
      }
  
      public String getTitle() {
          return title;
      }
  
      public void setTitle(String title) {
          this.title = title;
      }
  
      public String getIsbn() {
          return isbn;
      }
  
      public void setIsbn(String isbn) {
          this.isbn = isbn;
      }
  
      @Override
      public boolean equals(Object obj) {      
  
          if (this == obj) {
              return true;
          }
          
          if(obj == null) {
              return false;
          }
  
          if (getClass() != obj.getClass()) {
              return false;
          }
  
          IdManBook other = (IdManBook) obj;
          return Objects.equals(id, other.getId());
      }
  
      @Override
      public int hashCode() {
          return Objects.hash(id);
      }
  
  }
  