Key Points for Building a Traditional Java Web Project: Environment Setup, DAO, Service, Controller, and Spring Integration

The article provides a comprehensive checklist for developing a traditional Java web project, starting from environment preparation to the final controller layer.

Part 1: Environment Preparation

Maven command to create a web skeleton:

mvn archetype:create -DgroupId=net.rocketa -DartifactId=mywebapp -DarchetypeArtifactId=maven-archetype-webapp

IDEA settings for Maven sources, tests, and resources.

Logging dependencies: use slf4j as the API together with an implementation such as log4j, logback or commons-logging.

Database dependencies: include the driver JAR at runtime and a connection‑pool library (e.g., C3P0, DBCP).

Persistence framework: choose a DAO layer framework like MyBatis or Hibernate and add the corresponding Spring integration libraries.

Web layer dependencies: JSTL, tag libraries, Ajax JSON support, and the servlet-api for compilation.

Spring core modules: spring-core, spring-beans, spring-context.

Spring‑DB integration: spring-jdbc, spring-tx for declarative transactions.

Spring‑Web integration: spring-web, spring-webmvc.

Spring test support: spring-test for JUnit integration.

Part 2: DAO Layer

Define tables with proper engine (InnoDB), auto‑increment, charset, primary keys, indexes, and add creation‑time columns and comments.

Create DAO entities with getters/setters and consider relationship fields (one‑to‑one, one‑to‑many, many‑to‑many).

Design DAO interfaces and MyBatis mapper XML/annotations; keep SQL in XML for flexibility.

Key MyBatis points: global configuration (camel‑case mapping, generated keys), parameter and result type handling, OGNL expressions, and use of @Param for multiple primitive parameters.

Summarize: DAO work focuses on interface design and SQL writing, separating code from queries.

Part 3: Spring JUnit Unit Testing

After configuring Spring and writing DAO/SQL, write JUnit tests using annotations:

The Spring container is loaded, allowing beans to be injected for testing.

Part 4: Service Layer

Focus on business object encapsulation, DTOs between web and service, and exception handling (runtime exceptions trigger transaction rollback).

Typical pattern for catching and re‑throwing business exceptions:

Part 5: Controller Layer

RESTful design principles: use meaningful URIs, HTTP methods (GET, POST, PUT, DELETE) and proper status semantics.

Example request mapping with path variable and cookie handling:

Spring MVC configuration in web.xml includes the DispatcherServlet, <mvc:annotation-driven/>, <mvc:default-servlet-handler/>, and a ViewResolver with prefix/suffix settings.

Overall, the guide consolidates practical tips for setting up a Java web project, integrating Maven, Spring, MyBatis, and best practices for DAO, service, and controller layers.