MCP Authorization in practice with Spring AI and OAuth2

Last month, we explored how to secure Spring AI MCP Servers1 with the OAuth2 authorization framework. In the conclusion of that article, we mentioned we'd explore using standalone Authorization Servers for MCP Security and deviate from the then-current specification. Since we published the articl...

This Week in Spring - May 14th, 2024

Hi, Spring fans! Welcome to another installment of This Week in Spring! This week's highlights in the Spring ecosystem emphasize the ongoing advancements and applications of Spring AI. The discussions range from exploring the impressive VectorStore abstraction and enhanced structured output suppo...

Web applications and Project Loom

Introduction Project Loom aims to bring "easy-to-use, high-throughput, lightweight concurrency" to the JRE. One feature introduced by Project Loom is virtual threads. In this blog post, we'll be exploring what virtual threads mean for web applications using some simple web applications deployed o...

This Week in Spring - November 19th, 2024

Hi, Spring fans! How are you? Can you believe we're already staring at the end of the month? It's that time of the year when we see new releases, and the new releases reflect that frenzy! Soon: Spring Boot 3.4.0! Are you updated? Make sure you're updated! Remember: Spring projects leave open sour...

Deploy and Scale Spring Batch in the Cloud – with Adaptive Cost Control

May 21, 2024, at 9 AM PST You can now use Azure Spring Apps to effectively run Spring Batch applications with adaptive cost control. You only pay when batch jobs are running, and you can simply lift and shift your Spring Batch jobs with no code change. Spring Batch is a framework for processing...

Hypermedia and Browser Enhancement

Front end development these days is dominated by large JavaScript client side frameworks. There are plenty of good reasons for that, but it can be very inefficient for many use cases, and the framework engineering has become extremely complex. In this article, I want to explore a different...

This Week in Spring - March 12th, 2024

Hi, Spring fans! Welcome to another installment of This Week in Spring! And what a week it's going to be! Do this first: we need your help! Please answer some questions in our State of Spring survey! Join me for a look at the latest-and-greatest, chronicling how I got started with Spring Boot in...

This Week in Spring - September 19th, 2023 (Java 21 Edition)

Hi, Spring fans! Welcome to another installment of This Week in Spring - Java 21 edition! The big news, indeed, the biggest news, is that Java 21 is now available here! You should use SDKMAN to install it, like this: sdk install java 21-graalce && sdk default java 21-graalce. This install givews...

This Week in Spring - January 9th, 2023

Hi, Spring fans! As I write this Im on a plane winging my way to Helsinki, Finland. A new year and new journeys begin. Its going to be cold there. Wish me luck! Do you know what always warms me up? The thrill of learning. And this weeks no different. This week weve got some good stuff line up so...

This Week in Spring - December 6th, 2022

Hi, Spring fans! Welcome to another installment of This Week in Spring! How are you? You know what Ive wanted to do? See my friends on the Spring team in person since the pandemic descended. And, Im overjoyed to relate, Ive just had the privilege of a nice meeting with several of them last night...

This Week in Spring - August 23rd, 2022

Hi, Spring fans! Welcome to another installment of This Week in Spring! Weve got a ton to cover, so lets dive right into it! A Bootiful Podcast: Flowable founder Joram Barrez on a Bootiful Podcast on workflow, business process management, and more Building IoT Applications Using Fauna and Spring...

Spring Web Flow 3.0 M1 Released

It has been almost 4 years since the last set of Spring Web Flow releases. Nevertheless, the project continues to serve a specific need particularly well, arguably better than alternatives, and remains in active use. While there hasnt been a strong driver for new releases, the upcoming Spring...

Reflectionless Templates With Spring

A few Java libraries have shown up recently that use text templates, but compile to Java classes at build time. They can thus claim to some extent to be "reflection free". Together with potential benefits of runtime performance, they promise to be easy to use and integrate with GraalVM native ima...

Spring Modulith 0.3 released

Hot on the heels of Spring Boot 3.0.2, I am excited to announce the 0.3 release of Spring Modulith. The release is packed with improvements. We have tweaked a couple of things that might require your attention and a couple of adapting changes to your code. The most notable changes are: GH-114 – W...

This Week in Spring - October 18th, 2022

Hi, Spring fans! Howre you doin? Im doin alright! Last week I was in Antwerp, Belgium, for the amazing Devoxx BE show. I did a presentation with my friend and hero James Ward on Spring and Kotlin that was voted third most-liked talk at a show with more than 250 speakers! That was a personal caree...

This Week in Spring - April 8th, 2025

Hi, Spring fans! How are ya? I'm doing fine. Excited, even. You see, Spring AI M7 is coming soon! In theory, it drops on Thursday. Don't hold us to that — these things can change :- But soon , and it's turning out to be a whopper of a release! You should try upgrading your application to the new ...

This Week in Spring - April 2nd, 2024

Welcome, welcome, welcome, to another installment of This Week in Spring! You know, we've come a long way since you and I last spoke. It's April already! A new month! How bizarre. And, with the dawning of a new month, we're also more than 25% through this year! I sure hope you're paying attention...

Tackling the OAuth2 Client component model in Spring Security

In Spring Security 5, we saw many developments in the OAuth2 story with the introduction of OAuth2 Resource Server and OAuth2 Client into the framework. Today, it is quite convenient to develop applications that are secured by OAuth2 using the features available in OAuth2 Resource Server...

CVE-2026-41848

CVE-2026-41848...

This Week in Spring - January 26th, 2026

Hi, Spring fans! Welcome to another installment of This Week in Spring! As I write this, I cannot believe we're nearly at the end of the month! Time sure flies. Spring AI 2.0.0-M2 is available now Spring Modulith 2.1 M1, 2.0.2, and 1.4.7 released In last week's installment of A Bootiful Podcast ,...

Bootiful Spring Boot 3.4: Spring Boot

And now we’re back where we started: Spring Boot 3.4! This release is what pulls everything together. When you look at Spring Boot, remember that it normalizes the integration of all the projects it assembles and tries, wherever possible, to smooth out whatever integration issues might arise from...

Runtime efficiency with Spring (today and tomorrow)

With Spring Framework 6.1 and Spring Boot 3.2 general availability approaching, we would like to share an overview about several efforts the Spring team is pursuing to allow developers to optimize the runtime efficiency of their applications. We are going to cover the following technologies and u...

Spring Security 5.8.0-M1 and 6.0.0-M6 are released

On behalf of the team and everyone who has contributed, I am pleased to announce that Spring Security 5.8.0-M1 and 6.0.0-M6 are available now. This release includes dependency upgrades, bug fixes, and enhancements. Here are a few noteworthy changes: Deferred SecurityContext lookup...

This Week in Spring - June 14th, 2022

Hi, Spring fans! Welcome to another installment of This Week in Spring! Ive just arrived in beautiful Berlin, Germany, for the forthcoming We Are Developers show with more than five thousand attendees. I was in Toronto, Canada, for the epic SpringOne Tour installment there. Ive also had the...

cve-2026-47838 - MEDIUM - Unauthorized User Impersonation when Using X.509 Client Certificates

cve-2026-47838 - MEDIUM - Unauthorized User Impersonation when Using X.509 Client Certificates...

This Year in Spring – December 30th, 2025

Hi, Spring fans! Can you believe it? It's already the 30th of December! I celebrated Christmas with my family in Los Angeles, then we jumped on a flight headed for Southeast Asia to ring in the New Year with more friends and family. I'm sitting at a café in the sweltering city of Kuala Lumpur,...

This Week in Spring - February 14th, 2024

Hi, Spring fans! Welcome to another installment of This Week in Spring! Friends, tomorrow is Valentine's day, and I love Spring. So, it's a very exciting thing indeed to be able to share this week's jam-packed roundup. Let's dive right into it! Spring Tools 4.21.1 is now available In the latest...

This Week in Spring - August 29th, 2023 - the post SpringOne recovery blog

Hi, Spring fans! Welcome to another installment of This Week in Spring! I'm exhausted. Seriously. Last week was mental. If you need me, I'll be over sipping on a tea... But, before that, there's a ton of things to cover from this last week, as always, and there's no rest for the curious, so let's...

This Week in Spring - July 18th, 2023

Hi, Spring fans! Welcome to another installment of This Week in Spring! I'm in crazy cool Kuala Lumpur, Malaysia. If you're around, I'll be doing a presentation this Thursday the 20th of July, and I'd love to see you there! Then, after a quick vacation, it's off to Tokyo, Japan, where I'll also b...

This Week in Spring - November 29th, 2022 (Spring Boot 3 has arrived)

Hi, Spring fans! Its here! Its finally here, at long last! Spring Boot 3!! And of course with Spring Boot 3.0 comes a whole portfolio of integrated projects that have also been updated! Remember, a huge theme in this release is support for GraalVM native images, and thats now supported across the...

Microsoft is committed to the success of Java developers

Hi, Spring fans! This is a guest post from our friend Julia Liuson, President, Developer Division, Microsoft As a company, we are committed to making Java developers as efficient and productive as possible. This commitment means empowering you to use any tool, framework, and application server on...

Spring Tools 4.15.1 released

Dear Spring Community, I am happy to announce the 4.15.1 release of the Spring Tools 4 for Eclipse, Visual Studio Code, and Theia. fixes and improvements Spring Boot fixed: VScode incorrectly suggests removing @Autowired annotation from methods 787 Spring Boot fixed: VScode quick fix should not...

CVE-2026-41846

CVE-2026-41846...

Spring Framework DoS with Multipart Temp Files in WebFlux

A WebFlux server application that processes multipart requests creates temp files for parts larger than 10 K. Under some circumstances, temp files may remain not deleted after the request is fully processed. This allows an attacker to consume available disk space...

This Week in Spring - March 3rd, 2026

Hi Spring fans! Welcome to another rip-roaring installment of This Week in Spring! I'm writing this in an Uber en route to the airport to get to awsome Atlanta, GA, for Devnexus 2026! Who's goin'? You goin'? We - the Spring team - will be there in force! Come say hi at the boothes or come see our...

This Week in Spring - June 4th, 2024

Hi, Spring fans, from London! I'm in this fabulous country doing my level-headed best to refrain from dooing Mr. Bean bits, because, honestly, if I - an avid and prolific fan of Spring and its many beans - can't be "Mr. Bean," then I'm glad Rowan Atkinson is! I'm here for a SpringOne Tour event,...

The 2022 State of Spring Survey Report

Hi, Spring fans! You're awesome! I know you're awesome. You know you're awesome. And the Spring team works for you. We like working for you because you dream awesome dreams and build awesome things. And we can't work effectively with and for you if we don't know where everyone stands. Every year ...

CVE-2026-41844

CVE-2026-41844...

Function Calling in Java and Spring AI using the latest Mistral AI API

UPDATE: As of March 13, 2024, Mistral AI has integrated support for parallel function calling into their large model, a feature that was absent at the time of this blog's initial publication. Mistral AI, a leading developer of open-source large language models, unveiled the addition of Function...

This Week in Spring - February 20th, 2024

Hi, Spring fans! Welcome to another installment of This Week in Spring! How are you this fine 20th of February, 2024? I'm doing alright on this rainy 20th of Feburary here in San Francisco, and I hope you are too! We've got a ton of things to get into this week so let's dive right into it! Have y...

Improved Testcontainers Support in Spring Boot 3.1

There's been support for Testcontainers in Spring Boot for some time now, and Spring Boot 3.1 improves it further. But first, let's take a look at what Testcontainers is and how it's usually used. Testcontainers is an open source framework for providing throwaway, lightweight instances of...

MongoDB-backed Spring Batch jobs and more in Spring Boot 4.1

Spring Batch was introduced many years before MongoDB existed, and its design assumed the presence of a SQL database in which to store the state of Spring Batch jobs. But that was decades ago, and a common question for anyone new to Spring Batch was, "Why does this thing need to talk to a SQL...

This Week in Spring - April 22nd, 2025

Hi, Spring fans! Welcome to another installment of This Week in Spring , which I'm writing from magnificent Minneapolis, Minnesota, where I'm recording an amazing Frontend Masters course introducing Spring Boot. I love this article introducing Spring AI in JavaPro magazine Want to run an LLM...

All together now: Spring Boot 3.2, GraalVM native images, Java 21, and virtual threads with Project Loom,

This has been a very long time in coming, but finally we can create GraalVM native images that use Spring Boot via Spring Boot 3.2 and Java 21's virtual threads Project Loom! Why does all this matter? Each of these individual things, Project Loom, and GraalVM native images, offer compelling runti...

This Week in Spring - June 6th, 2023

Hi, Spring fans! Welcome to another installment of This Week in Spring! And what an insane week it's been! Long story short, I've spent 10-12 hours a day over the last five days migrating a dozen differnet applications and services from one GKE cluster to another, taking the time to update things...

Spring Tips: Learn Spring for GraphQL (parts 3 and 4 of an ongoing series)

Hi, Spring fans! In thi^^^ these installments, we continue our series introducing the Spring for GraphQL project. This series features Spring for GraphQL lead Rossen Stoyanchev @rstoya05 - whose work you may know from basically everything in the wide and wonderful world of Springdom having to do...

CVE-2026-41845

CVE-2026-41845...

cve-2026-59283 - MEDIUM - Spring Framework Safety Guard Bypass via SpEL Expression Compilation

cve-2026-59283 - MEDIUM - Spring Framework Safety Guard Bypass via SpEL Expression Compilation...

Denial of service in static resource handling on Windows platforms

Spring MVC and WebFlux applications are vulnerable to Denial of Service attacks when resolving static resources. More precisely, an application can be vulnerable when all the following are true: When all the conditions above are met, the attacker can send malicious requests that are slow to resol...

A Bootiful Podcast: Spring trainer extraordinairre Patrick Baumgartner

Hi, Spring fans! In this installment, I talked to Spring trainer extraordinaire, long-time community contributor, and Voxxed Days co-organizer for various shows in Switzerland. This talk was recorded live at Voxxed Days CERN!...