1.1 What is Spring boot?<\/h3>\n\n- Spring boot is a module that provides rapid application development feature to the spring framework including auto-configuration<\/strong>, standalone-code<\/strong>, and production-ready<\/strong> code<\/li>\n
- It creates applications that are packaged as jar<\/em> and are directly started using embedded servlet container (such as Tomcat, Jetty or Undertow). Thus, no need to deploy the war<\/em> files<\/li>\n
- It simplifies the maven configuration by providing the starter template and helps to resolve the dependency conflicts. It automatically identifies the required dependencies and imports them in the application<\/li>\n
- It helps in removing the boilerplate code, extra annotations, and XML configurations<\/li>\n
- It provides a powerful batch processing and manages the rest endpoints<\/li>\n
- It provides an efficient JPA-starter library to effectively connect the application with the relational databases<\/li>\n
- It offers a Microservice architecture and cloud configuration that manages all the application related configuration properties in a centralized manner.<\/li>\n<\/ul>\n
1.2 What is Docker?<\/h3>\n
In the present world, Docker<\/strong> is an important term,<\/p>\n\n- Often used in CI\/CD platform that packages and runs the application with its dependencies inside a container<\/li>\n
- Is a standard for Linux Containers<\/li>\n
- A Container<\/em> is a runtime that runs under any Linux kernel and provides a private machine-like space under Linux<\/li>\n<\/ul>\n\n
![\"\"](\"https:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2020\/06\/Docker-command-basics-img1-3.jpg\")
Fig. 1: Docker basic command<\/figcaption><\/figure>\n<\/div>\n1.3 Pagination<\/h3>\n
Consider a scenario where an endpoint returns a list of employees having 100000+ records. Now to retrieve such data from the backend is an expensive task as will consume some heavy resources.<\/p>\n
To rescue this resource consumption, Pagination<\/strong> came into the picture and played an important page. Pagination is a process of dividing data into suitable sizes to save resources (i.e. displaying a small number of all, by a page). Now this sizeable chunk will return the list of employees and other paging info (which we would see in this tutorial) based on the page-number and page-size parameters that are passed in an HTTP GET request. For instance \u2013 a request like \/employees\/getAll?pageNumber=0&pageSize=10<\/code> would return a batch of first 10 employees from the database and \/employees\/getAll?pageNumber=1&pageSize=10<\/code> would return the next batch of 10 employees and so on. . . <\/p>\n\n![\"Spring](\"https:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2020\/06\/springboot-pagination-tutorial-sample-pagination-response-img1.jpeg\")
Fig. 2: Sample pagination response
<\/figcaption><\/figure>\n<\/div>\nIn the spring framework, PaginationAndSortingRepository<\/code> which is an extension of CrudRepository<\/code> provides this functionality (i.e. to retrieve the records using the pagination and sorting techniques). To begin with, we will create a spring boot application that communicates with the Postgres database. But before going any further I\u2019m assuming that readers are aware of the concepts of creating and running a basic spring boot application.<\/p>\n2. Spring Boot Pagination Tutorial<\/h2>\n
Here is a systematic guide for implementing this tutorial.<\/p>\n
2.1 Application Pre-requisite<\/h3>\n
To start with this tutorial, we are hoping that users at present have the Docker installation completed. If someone needs to go through the Docker installation, please watch this<\/a> video.<\/p>\n2.2 Tools Used and Project Structure<\/h3>\n
We are using Eclipse, JDK 8, Maven, and Docker. In case you\u2019re confused about where you should create the corresponding files or folder, let us review the project structure of the spring boot application.<\/p>\n
\n![\"Spring](\"https:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2020\/06\/springboot-pagination-tutorial-project-structure-guide-img1.jpg\")
Fig. 3: Project structure<\/figcaption><\/figure>\n<\/div>\nLet us start building the application!<\/p>\n
3. Pulling the Postgres image from Docker Hub & Starting it<\/h2>\n
To have the Postgres up and working<\/em> on the localhost<\/em> environment, we will pull the image from Docker<\/span> and start the container. Users can refer the following commands to pull the image and later start the container.<\/p>\nDocker commands<\/em><\/span><\/p>\n\n\n
1.2 What is Docker?<\/h3>\n
In the present world, Docker<\/strong> is an important term,<\/p>\n Consider a scenario where an endpoint returns a list of employees having 100000+ records. Now to retrieve such data from the backend is an expensive task as will consume some heavy resources.<\/p>\n To rescue this resource consumption, Pagination<\/strong> came into the picture and played an important page. Pagination is a process of dividing data into suitable sizes to save resources (i.e. displaying a small number of all, by a page). Now this sizeable chunk will return the list of employees and other paging info (which we would see in this tutorial) based on the page-number and page-size parameters that are passed in an HTTP GET request. For instance \u2013 a request like In the spring framework, Here is a systematic guide for implementing this tutorial.<\/p>\n To start with this tutorial, we are hoping that users at present have the Docker installation completed. If someone needs to go through the Docker installation, please watch this<\/a> video.<\/p>\n We are using Eclipse, JDK 8, Maven, and Docker. In case you\u2019re confused about where you should create the corresponding files or folder, let us review the project structure of the spring boot application.<\/p>\n Let us start building the application!<\/p>\n To have the Postgres up and working<\/em> on the localhost<\/em> environment, we will pull the image from Docker<\/span> and start the container. Users can refer the following commands to pull the image and later start the container.<\/p>\n Docker commands<\/em><\/span><\/p>\n\n
1.3 Pagination<\/h3>\n
\/employees\/getAll?pageNumber=0&pageSize=10<\/code> would return a batch of first 10 employees from the database and \/employees\/getAll?pageNumber=1&pageSize=10<\/code> would return the next batch of 10 employees and so on. . . <\/p>\n
<\/figcaption><\/figure>\n<\/div>\nPaginationAndSortingRepository<\/code> which is an extension of CrudRepository<\/code> provides this functionality (i.e. to retrieve the records using the pagination and sorting techniques). To begin with, we will create a spring boot application that communicates with the Postgres database. But before going any further I\u2019m assuming that readers are aware of the concepts of creating and running a basic spring boot application.<\/p>\n2. Spring Boot Pagination Tutorial<\/h2>\n
2.1 Application Pre-requisite<\/h3>\n
2.2 Tools Used and Project Structure<\/h3>\n
3. Pulling the Postgres image from Docker Hub & Starting it<\/h2>\n