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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.
Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.
Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.
With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.
Try a 14-Day Free Trial of Orkes Conductor today.
Mocking is an essential part of unit testing, and the Mockito library makes it easy to write clean and intuitive unit tests for your Java code.
Get started with mocking and improve your application tests using our Mockito guide:
Spring 5 added support for reactive programming with the Spring WebFlux module, which has been improved upon ever since. Get started with the Reactor project basics and reactive programming in Spring Boot:
Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.
But these can also be overused and fall into some common pitfalls.
To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:
Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:
Yes, Spring Security can be complex, from the more advanced functionality within the Core to the deep OAuth support in the framework.
I built the security material as two full courses - Core and OAuth, to get practical with these more complex scenarios. We explore when and how to use each feature and code through it on the backing project.
You can explore the course here:
Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.
Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.
With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.
Try a 14-Day Free Trial of Orkes Conductor today.
Spring Data JPA is a great way to handle the complexity of JPA with the powerful simplicity of Spring Boot.
Get started with Spring Data JPA through the guided reference course:
Refactor Java code safely — and automatically — with OpenRewrite.
Refactoring big codebases by hand is slow, risky, and easy to put off. That’s where OpenRewrite comes in. The open-source framework for large-scale, automated code transformations helps teams modernize safely and consistently.
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1. Introduction
The Server Push technology — part of HTTP/2 (RFC 7540) — allows us to send resources to the client proactively from the server-side. This is a major change from HTTP/1.X pull-based approach.
One of the new features that Spring 5 brings – is the server push support that comes with Jakarta EE 8 Servlet 4.0 API. In this article, we’ll explore how to use server push and integrate it with Spring MVC controllers.
2. Maven Dependency
Let’s start by defining dependencies we’re going to use:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>6.1.5</version>
</dependency>
<dependency>
<groupId>jakarta.servlet</groupId>
<artifactId>jakarta.servlet-api</artifactId>
<version>6.1.0-M2</version>
<scope>provided</scope>
</dependency>The most recent versions of spring-mvc and servlet-api can be found on Maven Central.
3. HTTP/2 Requirements
To use server push, we’ll need to run our application in a container that supports HTTP/2 and the Servlet 4.0 API. Configuration requirements of various containers can be found here, in the Spring wiki.
Additionally, we’ll need HTTP/2 support on the client-side; of course, most current browsers do have this support.
4. PushBuilder Features
The PushBuilder interface is responsible for implementing server push. In Spring MVC, we can inject a PushBuilder as an argument of the methods annotated with @RequestMapping.
At this point, it’s important to consider that – if the client doesn’t have HTTP/2 support – the reference will be sent as null.
Here is the core API offered by the PushBuilder interface:
- path (String path) – indicates the resource that we’re going to send
- push() – sends the resource to the client
- addHeader (String name, String value) – indicates the header that we’ll use for the pushed resource
5. Quick Example
To demonstrate the integration, we’ll create the demo.jsp page with one resource — logo.png:
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>PushBuilder demo</title>
</head>
<body>
<span>PushBuilder demo</span>
<br>
<img src="<c:url value="/resources/logo.png"/>" alt="Logo"
height="126" width="411">
<br>
<!--Content-->
</body>
</html>We’ll also expose two endpoints with the PushController controller — one that uses server push and another that doesn’t:
@Controller
public class PushController {
@GetMapping(path = "/demoWithPush")
public String demoWithPush(PushBuilder pushBuilder) {
if (null != pushBuilder) {
pushBuilder.path("resources/logo.png").push();
}
return "demo";
}
@GetMapping(path = "/demoWithoutPush")
public String demoWithoutPush() {
return "demo";
}
}Using the Chrome Development tools, we can see the differences by calling both endpoints.
When we call the demoWithoutPush method, the view and the resource is published and consumed by the client using the pull technology:
When we call the demoWithPush method, we can see the use of the push server and how the resource is delivered in advance by the server, resulting in a lower load time:
The server push technology can improve the load time of the pages of our applications in many scenarios. That being said, we do need to consider that, although we decrease the latency, we can increase the bandwidth – depending on the number of resources we serve.
It’s also a good idea to combine this technology with other strategies such as Caching, Resource Minification, and CDN, and to run performance tests on our application to determine the ideal endpoints for using server push.
6. Conclusion
In this quick tutorial, we saw an example of how to use the server push technology with Spring MVC using the PushBuilder interface, and we compared the load times when using it versus the standard pull technology.
The code backing this article is available on GitHub. Once you're logged in as a Baeldung Pro Member, start learning and coding on the project.
