spring源码(一)：运行Spring源码

环境准备

• JDK8
• Maven3.5.4

下载并编译

1. 打开Spring官网，选择github地址
2. 选择合适下载方式，可以下载zip包，也可以用git clone
3. 进入下载后的目录，切换到5.2.x分支，在build.gradle修改阿里云镜像配置具体参考

    repositories {
        maven { url 'http://maven.aliyun.com/nexus/content/groups/public/' }
        maven { url 'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
    }

        repositories {
            maven { url 'http://maven.aliyun.com/nexus/content/groups/public/' }
            maven { url 'http://maven.aliyun.com/nexus/content/repositories/jcenter'}
            mavenCentral()
            maven { url "https://repo.spring.io/libs-spring-framework-build" }
        }

4. 项目导入idea，文档地址

4.1 Precompile spring-oxm with ./gradlew :spring-oxm:compileTestJava
(在控制台预编译spring-oxm，控制台执行./gradlew :spring-oxm:compileTestJava)
4.2 Import into IntelliJ (File -> New -> Project from Existing Sources -> Navigate to directory -> Select build.gradle)
(idea导入项目)
4.3 When prompted exclude the spring-aspects module (or after the import via File-> Project Structure -> Modules)
(排除spring-aspects模块，AspectJ编译器Ajc后续在aop会下载这个编译器)
4.4 Code away

5. 可以在编码前需要去掉src下的checkstyle文件夹下的checkstyle.xml规则，具体参考

编码

1. 首先在spring-framework新建spring-demo模块，并在build.gradle引入context依赖

plugins {
    id 'java'
}

group 'org.springframework'
version '5.2.17.BUILD-SNAPSHOT'

sourceCompatibility = 1.8

repositories {
    mavenCentral()
}

dependencies {
    compile(project(":spring-context"))
    testCompile group: 'junit', name: 'junit', version: '4.12'
}

2. 在src\main新建com.imooc.service包并新建WelcomeService接口和对应实现类WelcomeServiceImpl

package com.imooc.service;

public interface WelcomeService {

    String sayHello(String name);
}

public class WelcomeServiceImpl implements WelcomeService {

    @Override
    public String sayHello(String name) {
        System.out.println("欢迎您：" + name);
        return "欢迎您：" + name;
    }
}

3. 在src\main\resource\spring新建spring-config.xml，配置相关bean

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
    <bean id="welcomeService" class="com.imooc.service.impl.WelcomeServiceImpl"/>
</beans>

4. 新建入口类

public class Entrance {

    public static void main(String[] args) {
        ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext(
                "classpath:spring/spring-config.xml");
        WelcomeService welcomeService = applicationContext.getBean(WelcomeService.class);
        welcomeService.sayHello("spring xml方式获取bean");
    }
}

5. 运行Entrace的main方法，控制台输出

欢迎您：spring xml方式获取bean

6. 至此下载编译运行源码成功

小结

1. 编译源码需要下载大量包，如果有下载失败可以重复多下载几次
2. 需要使用高版本的idea，获取高版本kotlin语法支持