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[TOC] # 简介 ![](https://box.kancloud.cn/d74d20d54f32194ee03effdee9bc468b_750x454.png) 1. core container a) beans与core 它们提供spring框架最基本功能，包含ioc与di b) context 上下文对象，基于beans与cores c) spel它是sprng提供的一个表达式语言 2. Data access/integration a) 数据访问 b) 集成 3. Web a) Spring本身提供spring mvc b) 也可以与其它的web层进行集成 4. AOP AOP大部分情况下是使用动态代理来实现的。 5. Test 使用spring可以方便的进行测试 # IOC Inverse of control反转控制将我们创建对象的方式反转了以前对象的创建是由我们开发人员自己维护.包括依赖关系也是自己注入使用了spring之后,对象的创建以及依赖关系可以由spring完成创建以及注入反转控制就是反转了对象的创建方式,从我们创建反转给了程序(spring) # DI Dependency Injection依赖注入实现IOC思想需要DI做支持注入方式: * set方式注入 * 构造方法注入 * 字段注入注入类型: * 值类型注入(8大基本数据类型) * 引用类型注入(将依赖对象注入) # ApplicationContext和BeanFactory 在spring IOC容器读取Bean配置创建Bean实例之前,必须对它进行实例化,只有在容器实例化后,才可以从IOC容器里获取Bean实例并使用 spring提供了两种类型的IOC容器实现 * BeanFactory:IOC容器的基本实现 * ApplicationContext:提供了更多的高级特性,是BeanFactory的子接口 * BeanFactory是Spring框架的基础设施,面向spring本身 ApplicationContext:提供了更多的高级特性,是BeanFactory的子接口 * BeanFactory是spring框架的基础设施,面向spring本身 ApplicationContext面向使用spring框架的开发者,几乎所有的应用场合都直接使用ApplicationContext而非底层的BeanFactory * 无论使用哪种,配置文件都是相同的 # ApplicationContext的主要实现类 ApplicationContext的主要实现类: - classPathXmlApplicationContext:从类路径下加载配置文件 - FileSystemXmlApplicationContext:从文件系统中加载配置文件,全路径 - AnnotationConfigApplicationContext: 它是用于读取注解创建容器的 ConfigurableApplicationContext扩展于ApplicationContext,新增加两个主要方法refresh()和close(),让ApplicationContext具有启动,刷新和关闭上下文的能力 ApplicationContext在初始化上下文时就实例化所有单例的Bean WebApplicationContext是专门为web应用准备的,他允许从相对应web根目录的路径中完成初始化工作 # 例子 ## 创建对象 ~~~ package studySpring; public class User { public User() { System.out.println("User对象空参构造方法!!!!"); } private String name; private Integer age; private Car car; public User(String name, Car car) { System.out.println("User(String name, Car car)!!"); this.name = name; this.car = car; } public User(Car car, String name) { System.out.println("User(Car car,String name)!!"); this.name = name; this.car = car; } public User(Integer name, Car car) { System.out.println("User(Integer name, Car car)!!"); this.name = name + ""; this.car = car; } public Car getCar() { return car; } //setter/getter public void init() { System.out.println("我是初始化方法!"); } public void destory() { System.out.println("我是销毁方法!"); } @Override public String toString() { return "User [name=" + name + ", age=" + age + ", car=" + car + "]"; } } ~~~ ~~~ package studySpring; public class Car { private String name; private String color; //getter/setter @Override public String toString() { return "Car [name=" + name + ", color=" + color + "]"; } } ~~~ ## 测试在applicationContext.xml中写 ~~~ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd ">   <bean name="user" class="studySpring.User" ></bean>  <import resource="studySpring/applicationContext.xml"/> </beans> ~~~ 然后写个类测试下 ~~~ package hello; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import bean.User; public class Demo { @Test public void fun1() { // 1.创建容器对象,因为直接在src下,就写applicationContext.xml ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml"); // 2.向容器要User对象 User u = (User) ac.getBean("user"); // 打印User对象 System.out.println(u); } } ~~~ ApplicationContext它是BeanFactory的一个子接口，我们在使用时使用的是AppliCationContext的实现类ClassPathXmlApplicationContext # 配置文件 ## 配置文件约束 ~~~ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" //上面两个是基础IOC的约束，必备 xmlns:context="http://www.springframework.org/schema/context" //上面一个是开启注解管理Bean对象的约束 xmlns:aop="http://www.springframework.org/schema/aop" //aop的注解约束 xmlns:tx="http://www.springframework.org/schema/tx" //事务的约束 xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd //上面两个是基础IOC的约束，必备 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd //上面一个是开启注解管理Bean对象的约束 http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd //aop的注解约束 http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> //事务的约束 </beans> ~~~ ![](https://img.kancloud.cn/8c/91/8c9168624d96b7a432ad4b3cdeab679b_961x309.png) # maven ~~~ <dependencies>  <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.10.0</version> </dependency>  <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-annotations</artifactId> <version>2.10.0</version> </dependency>  <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-core</artifactId> <version>2.10.0</version> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.14</version> </dependency>  <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.12</version> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-expression</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency>   <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aspects</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.18</version> </dependency>   <dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3</version> </dependency>  <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.9.1</version> </dependency>  <dependency> <groupId>commons-dbcp</groupId> <artifactId>commons-dbcp</artifactId> <version>1.2.2</version> </dependency> </dependencies> ~~~ ~~~ <properties> <spring.version>5.1.2.RELEASE</spring.version> <maven.compiler.source>9</maven.compiler.source> <maven.compiler.target>9</maven.compiler.target> </properties> ~~~