Spring Boot 4.0 (November 2025) is a major release built on Spring Framework 7 and Java 17+. It’s the most significant Spring release since Boot 3’s Jakarta EE migration. This article covers every change that affects a practicing developer. Minimum Requirements Spring Boot 3.x Spring Boot 4.0 Java 17 17 (baseline), 21 recommended Spring Framework 6.x 7.x Jakarta EE 10 11 Tomcat 10.x 11.x Hibernate 6.x 7.x Gradle (if used) 7.

Introduction After reading and processing data, your batch job needs to write results somewhere. Spring Batch provides two essential writers: FlatFileItemWriter — writes items to CSV or any delimited/formatted flat file JdbcBatchItemWriter — writes items to a database using JDBC batch inserts/updates Both are transactional and restartable. This article covers both in depth, plus transaction semantics you must understand to avoid duplicates and partial writes. How Writers Work in Spring Batch Writers receive a Chunk<O> — a list of all items processed in the current transaction.

In this article you’ll create a Spring Boot application, add a REST endpoint, and run it — all in under 10 minutes. Then you’ll understand exactly what each piece does. What you’ll build: A Spring Boot app that responds to GET /hello with "Hello, Spring Boot!". Prerequisites JDK 21 or higher installed (java -version to verify) Maven 3.9+ installed (mvn -version to verify) An IDE — IntelliJ IDEA (recommended), VS Code with Java extension, or Eclipse Step 1: Generate the Project Go to start.