Introducing Spring Framework

Chapter 1 ■ Your First Spring Application
■ ■Note Appendix A shows you how to install Gradle.
Hello World Example
Let’s start with the famous and well known “Hello World” example for your first Spring Application. You need to create
the following folder structure (either in Windows or Unix).
• build.gradle
••• src
••• main
••• java
••• com
••• apress
••• isf
••• spring
• Application.java
• HelloWorldMessage.java
• MessageService.java
Why do you need this folder structure? Gradle follows a community standard for creating Java applications, and
primarily is based on Maven (an XML build tool that still is widely used) and a convention. So everything that belongs
to the src/main/java folder will be compiled, and the result will be output to a build folder.
Listing 1-1 shows your build.gradle file. This file is the key for Gradle to run. In this file, you specify what plug-ins
you are going to use. Every plug-in has its own tasks that you can run, such as compile, build, test, jar, etc. Also, you
can specify what repositories to use in order to look for the dependencies you specified. In this example, you are
going to use the spring-context module version 4.0.5.RELEASE that Gradle will download with all its dependencies.
Furthermore, you are telling it that you are going to pass the name of the mainClass in order to run it.
Listing 1-1. build.gradle
apply plugin: 'java'
apply plugin: 'application'
mainClassName = System.getProperty("mainClass")
repositories {
mavenCentral()
}
dependencies {
compile 'org.springframework:spring-context:4.0.5.RELEASE'
}
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