Essential Spring 3 & 4 Modules and Their Required JARs

If you use Spring without Spring Boot, every feature requires a specific JAR, and the sheer number of possible dependencies can cause confusion and errors. This article organizes the core modules of Spring 3 and Spring 4 and lists the corresponding JAR files needed for each module.

Spring 3 Framework Structure

Spring 4 Framework Structure

Compared with Spring 3, Spring 4 removes Struts and adds Messaging and WebSocket support.

Core Container (Core Container)

spring-core

: Core classes used extensively by other modules. spring-beans: Support for defining beans. spring-context: Runtime Spring container. spring-context-support: Integration support for third‑party packages such as mail services and view resolvers. spring-expression: Spring Expression Language.

AOP

spring-aop

: Proxy‑based AOP support. spring-aspects: AspectJ‑based AOP support. spring-instrument: Class‑level utilities and ClassLoader implementations for servers. spring-instrument-tomcat: Tomcat‑specific instrumentation.

Data Access / Integration

spring-jdbc

: JDBC database access support. spring-tx: Programmatic and declarative transaction support. spring-orm: Object‑relational mapping support. spring-oxm: Object‑XML mapping support. spring-jms: Java Message Service support.

Web

spring-web

: Basic web integration features. spring-webmvc: Servlet‑based MVC framework. spring-webmvc-portlet: Portlet‑based MVC implementation. spring-websocket: WebSocket functionality.

Test & Messaging

spring-test

: Testing utilities, JUnit and mock support. spring-messaging: Support for messaging architectures and protocols.

Knowing exactly which JAR each Spring module requires dramatically reduces the chance of errors. Using Spring Boot can further simplify dependency management.