Search⌘ K
Home/
Courses/
Spring Data: Bridging Multiple Databases

Solution: Reservation Queue

Here's the solution to the reservation queue challenge.

We'll cover the following...

Solution

Let’s discuss the solution for implementing a book reservation queue.

Update the Book class

First, we add the Boolean available property to the Book class.

Java
package com.smartdiscover.model;
import lombok.Data;
import org.springframework.data.redis.core.RedisHash;
import org.springframework.data.redis.core.index.Indexed;
import java.io.Serializable;
import java.util.List;
import java.util.stream.Collectors;
@RedisHash("Book")
@Data
public class Book implements Serializable {
    private String id;
    @Indexed
    private String name;
    private String summary;
    private Boolean available;
    private List<Author> authors;
    @Override
    public String toString() {
        return "Book{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", summary='" + summary + '\'' +
                ((null != authors) ? ", authors=" + authors.stream().map(i -> i.getFullName()).collect(Collectors.toList()) + '\'' : "") +
                '}';
    }
}

Create the User class

Then, we create the User class in the com.smartdiscover.model package.

Java
package com.smartdiscover.model;
import lombok.Data;
import org.springframework.data.redis.core.RedisHash;
import org.springframework.data.redis.core.index.Indexed;
@RedisHash("User")
@Data
public class User {
    private String id;
    @Indexed
    private String firstName;
    @Indexed
    private String lastName;
}

Here’s an explanation of the code:

  • Lines 7–9: We add annotations like @Data and @RedisHash to transform a class into a Redis hash.

  • Line 11: We add the id identifier.

  • Lines 13 and 14: We add the firstName property with the @Indexed annotation to let Redis index the property values.

  • Lines 16 and 17: We add the lastName property with the @Indexed annotation. ...