Java

Legacy Java to Spring Boot Blueprint

Step-by-step migration from legacy Java EE applications to modern Spring Boot

Java EE on WebSphere to Spring Boot Blueprint

Migrate Java EE applications off WebSphere onto Spring Boot with embedded servers, externalized config, and container-native packaging.

Apache Struts to Spring MVC Blueprint

Replace legacy Apache Struts web applications with Spring MVC to remove unmaintained framework risk and modernize the web tier.

Java to Kotlin Backend Adoption Blueprint

Incrementally adopt Kotlin in a Java backend using full interop, null-safety gains, and coroutines for concurrent code.

EJB to REST Services Blueprint

Replace remote EJB interfaces with HTTP REST services to decouple clients from RMI and enable language-agnostic integration.

Java 8 to Java 21 LTS Modernization Blueprint

Upgrade long-lived Java 8 applications to the Java 21 LTS runtime, adopting modern language features and resolving JDK module and API changes.

Migrations5

Android Java to Kotlin Migration

Incrementally convert an Android codebase from Java to Kotlin

COBOL to Java Migration

Mainframe COBOL modernization to Java microservices

Java 8 to Java 17 Migration

Upgrade Java runtime from 8 to 17, updating dependencies and build tooling

Spring Boot 2 to Spring Boot 3 Migration

Upgrade Spring Boot 2.x to 3.x with Java 17+ and Jakarta EE

Spring MVC to Spring WebFlux Migration

Migrate Spring MVC apps to reactive Spring WebFlux where it provides clear value

Products4

Java

High-level, class-based, object-oriented programming language

Spring Boot

Java-based framework for production-ready applications

Quarkus

Kubernetes-native Java framework for cloud deployments

Micronaut

Modern JVM-based framework for microservices

Playbooks3

Playbook

Java EE to Spring Boot Program Playbook

An enterprise program for migrating Java EE applications to Spring Boot with modern build, runtime, and deployment practices.

Playbook

Java 8 to 17 Runtime Modernization Program Playbook

A fleet program to upgrade Java services from Java 8 to a modern LTS runtime with build, module, and dependency modernization.

Playbook

Spring Boot 2 to 3 Upgrade Program Playbook

A fleet program to upgrade Spring Boot 2 services to Spring Boot 3, covering the Jakarta namespace move, Java baseline, and observability changes.

Checklists1

Checklist

Java Framework Upgrade Pre-Flight Checklist

Pre-flight checks for upgrading a Java application's runtime and framework, such as Java 8 to 17 or Spring Boot 2 to 3.

Stacks10

Spring Cloud Stack

Spring Boot, Spring Cloud, Kubernetes - Enterprise Java

Spring Boot + Thymeleaf

A Java stack pairing Spring Boot with the Thymeleaf template engine for server-rendered web applications with robust enterprise tooling.

Spring Boot Enterprise Stack

Java backend stack built on Spring Boot with PostgreSQL and Redis for production REST services and enterprise applications.

Quarkus Cloud-Native Java Stack

Cloud-native Java backend using Quarkus with GraalVM native compilation and PostgreSQL for fast-starting, low-memory containerized services.

Micronaut JVM Microservices Stack

JVM microservices stack using Micronaut with ahead-of-time compilation and PostgreSQL for low-memory, fast-starting services and serverless functions.

React + Spring Boot

A React frontend backed by a Java Spring Boot REST API, a workhorse enterprise stack for large, long-lived business applications.

Angular + Spring Boot

An Angular frontend over a Spring Boot Java backend, a strongly opinionated, fully typed enterprise stack favored by large IT organizations.

Vert.x Reactive Stack

A polyglot, event-driven toolkit on the JVM built around a non-blocking event loop and the reactor pattern for high-concurrency, low-latency services.

Play Framework (Scala)

A reactive, stateless web framework on the JVM written for Scala (and Java), built on Akka for non-blocking, high-throughput web applications and APIs.

Spring WebFlux Reactive

Spring's reactive, non-blocking web stack built on Project Reactor and Netty, for high-concurrency services that need backpressure and efficient resource use.

Comparisons7

Go vs Java

Go offers a lean runtime and fast startup for cloud services, while Java brings a mature ecosystem, the JVM, and decades of enterprise tooling.

Java vs Kotlin

Both run on the JVM and interoperate fully, but Kotlin offers more concise, modern syntax and null safety while Java offers ubiquity and the longest track record.

Java vs C#

Two mature, statically typed languages with managed runtimes: Java on the JVM with broad portability, C# on .NET with strong language features and tooling.

REST in Go vs REST in Java

Building REST APIs in Go with its lean standard library versus in Java with mature frameworks like Spring Boot. Different trade-offs in speed, structure, and tooling.

Java Virtual Threads vs Reactive Programming

Two approaches to scalable concurrency on the JVM: Project Loom's virtual threads keep simple blocking code, while reactive programming uses non-blocking streams.

ASP.NET Core vs Spring Boot

ASP.NET Core is Microsoft's high-performance .NET framework; Spring Boot is the dominant Java framework. Both are mature, enterprise-grade choices.

Kotlin vs Java for Android

Kotlin is Google's preferred, modern language for Android; Java is the original, ubiquitous JVM language with the largest legacy footprint.

Benchmarks7

JMH (Java Microbenchmark Harness)

The standard harness for writing reliable JVM microbenchmarks, widely used to measure data-processing and serialization library performance on the JVM.

SPECjbb 2015

Java server benchmark modeling a supermarket company's transaction processing to measure JVM and server-side Java throughput and latency.

Apache JMeter

Mature, GUI-driven Java load-testing tool for simulating complex multi-protocol user scenarios and measuring throughput, latency, and error rates.

SPECjbb 2015

Standard Java server benchmark modeling a supermarket company's business logic to measure throughput and critical response-time performance.

SPECjvm 2008

Benchmark suite measuring core Java Virtual Machine performance across compute-intensive workloads independent of application or hardware tuning.

Renaissance JVM Benchmark Suite

Modern JVM benchmark suite using real-world concurrent and parallel workloads to stress runtime optimization, GC, and JIT compilers.