Pagination and sorting with Pageable in Spring Boot - Mini Project: Build & Apply

Pagination and sorting with Pageable in Spring Boot

📖 Scenario: You are building a simple Spring Boot application to manage a list of books in a library. The library has many books, so you want to show the books page by page and allow sorting by title or author.

🎯 Goal: Build a Spring Boot REST controller that returns a paginated and sorted list of books using Spring Data's Pageable interface.

📋 What You'll Learn

Create a list of books as initial data

Add a Pageable parameter to the controller method

Use the Pageable to return a paginated and sorted page of books

Complete the REST controller to handle requests with pagination and sorting

💡 Why This Matters

🌍 Real World

Pagination and sorting are common in web applications to improve user experience by loading data in small chunks and allowing users to order data by different fields.

💼 Career

Understanding how to use Spring Data's Pageable interface is essential for backend developers working with Spring Boot to build scalable and user-friendly APIs.

1

Create initial book data

Create a List<Book> called books with these exact entries: new Book(1L, "Spring Boot Basics", "John Doe"), new Book(2L, "Java Fundamentals", "Jane Smith"), new Book(3L, "REST APIs", "Alice Johnson"), new Book(4L, "Microservices", "Bob Brown").

Spring Boot

import java.util.List;

public class BookController {
    // Create the books list here
    // Your code here
}

Need a hint?

Use List.of() to create an immutable list of Book objects with the exact data.

2

Add Pageable parameter to controller method

Add a public method called getBooks that takes a Pageable pageable parameter and returns a Page<Book>. Do not implement the method body yet.

Spring Boot

import java.util.List;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;

public class BookController {
    List books = List.of(
        new Book(1L, "Spring Boot Basics", "John Doe"),
        new Book(2L, "Java Fundamentals", "Jane Smith"),
        new Book(3L, "REST APIs", "Alice Johnson"),
        new Book(4L, "Microservices", "Bob Brown")
    );

    // Add the getBooks method signature here
    // Your code here
}

Need a hint?

Define the method with the exact name getBooks, return type Page<Book>, and a single parameter Pageable pageable.

3

Implement pagination and sorting logic

Inside the getBooks method, create a PageImpl<Book> object that returns a sublist of books based on pageable.getPageNumber() and pageable.getPageSize(). Use pageable.getSort() to sort the list by title or author before paging.

Spring Boot

import java.util.List;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.Sort;
import java.util.stream.Collectors;

public class BookController {
    List books = List.of(
        new Book(1L, "Spring Boot Basics", "John Doe"),
        new Book(2L, "Java Fundamentals", "Jane Smith"),
        new Book(3L, "REST APIs", "Alice Johnson"),
        new Book(4L, "Microservices", "Bob Brown")
    );

    public Page getBooks(Pageable pageable) {
        // Sort and paginate the books list here
        // Your code here
    }
}

Need a hint?

Use a stream to sort the books by the properties in pageable.getSort(). Then calculate the start and end indexes for the page and create a PageImpl with the sublist.

4

Complete the REST controller with annotations

Add the @RestController annotation to the class and @GetMapping("/books") to the getBooks method. Add @RequestParam to accept page, size, and sort parameters automatically via Pageable.

Spring Boot

import java.util.List;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.Sort;
import java.util.stream.Collectors;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;

@RestController
public class BookController {
    List books = List.of(
        new Book(1L, "Spring Boot Basics", "John Doe"),
        new Book(2L, "Java Fundamentals", "Jane Smith"),
        new Book(3L, "REST APIs", "Alice Johnson"),
        new Book(4L, "Microservices", "Bob Brown")
    );

    // Add @GetMapping and @RequestParam annotations here
    // Your code here
}

Need a hint?

Add @RestController above the class and @GetMapping("/books") above the getBooks method to make it a REST endpoint that accepts pagination and sorting parameters.