spring(ioc)

程序员文章站 2022-07-12 13:54:28

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什么是spring，它能够做什么?

Spring是一个开源框架，它由Rod Johnson创建。它是为了解决企业应用开发的复杂性而创建的。
Spring使用基本的JavaBean来完成以前只可能由EJB完成的事情。
然而，Spring的用途不仅限于服务器端的开发。从简单性、可测试性和松耦合的角度而言，任何Java应用都可以从Spring中受益。
目的：解决企业应用开发的复杂性
功能：使用基本的JavaBean代替EJB，并提供了更多的企业应用功能
范围：任何Java应用
简单来说，Spring是一个轻量级的控制反转(IoC)和面向切面(AOP)的容器框架。
中间层框架、万能胶
struts2
spring
hibernate
容器框架
JavaBean 项目中的一个个类
IOC和AOP

什么是控制反转(或依赖注入)
控制反转(IoC=Inversion of Control)IoC，用白话来讲，就是由容器控制程序之间的（依赖）关系，而非传统实现中，由程序代码直接操控。这也就是所谓“控制反转”的概念所在：(依赖)控制权由应用代码中转到了外部容器，控制权的转移，是所谓反转。
IoC还有一个另外的名字：“依赖注入 (DI=Dependency Injection)” ，即由容器动态的将某种依赖关系注入到组件之中
案例：实现Spring的IoC
IOC/DI
将以前由程序员实例化对象/赋值的工作交给了spring处理

核心依赖包

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-context</artifactId>
  <version>4.3.10.RELEASE</version>
</dependency>

set注入

UserAction.java

package com.qukang.ioc.web;

import java.util.ArrayList;
import java.util.List;

import com.qukang.ioc.biz.UserBiz;
import com.qukang.ioc.biz.UserBizImpl1;
/**
 * ioc的注入方式及各类类型
 * set注入
 * 		基本类型String
 * 		数组
 * 		自定义类型
 * 构造注入
 * 
 * 自动装配
 * @author VULCAN
 *
 */
public class UserAction {
	private UserBiz userBiz;
	private String uname;
	private int age;
	private List<String> hobby;
	
	public String getUname() {
		return uname;
	}


	public void setUname(String uname) {
		this.uname = uname;
	}


	public int getAge() {
		return age;
	}


	public void setAge(int age) {
		this.age = age;
	}


	public List<String> getHobby() {
		return hobby;
	}


	public void setHobby(List<String> hobby) {
		this.hobby = hobby;
	}


	public UserBiz getUserBiz() {
		return userBiz;
	}


	public void setUserBiz(UserBiz userBiz) {
		this.userBiz = userBiz;
	}


	public void upload() {
		userBiz.upload();
	}
	
	public void test1() {
		System.out.println(this.uname);
		System.out.println(this.age);
		System.out.println(this.hobby);
	}
}

spring-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:context="http://www.springframework.org/schema/context"
   xmlns:tx="http://www.springframework.org/schema/tx"
   xmlns:aop="http://www.springframework.org/schema/aop"
   xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
	<bean class="com.qukang.ioc.biz.UserBizImpl2" id="userBiz"></bean>
	<bean class="com.qukang.ioc.web.UserAction" id="xxx">
	<!-- set注入用property标签 -->
		<property name="userBiz" ref="userBiz"></property>
		<property name="uname" value="zs"></property>
		<property name="age" value="22"></property>
		<property name="hobby">
			<list>
			<value>唱</value>
			<value>跳</value>
			<value>RAP</value>
			<value>篮球</value>
			</list>
		</property>
	</bean>
	<bean class="com.qukang.ioc.web.OrderAction" id="ttt">
		<property name="userBiz" ref="userBiz"></property>
	</bean>
</beans>

IoTest测试类

package com.qukang.ioc.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.qukang.ioc.web.OrderAction;
import com.qukang.ioc.web.UserAction;

public class IocTest {
	public static void main(String[] args) {
//		UserAction userAction=new UserAction();
//		userAction.upload();
		
		ApplicationContext springContext=new ClassPathXmlApplicationContext("/spring-context.xml");
		UserAction userAction =(UserAction)springContext.getBean("xxx");
//		OrderAction orderAction =(OrderAction)springContext.getBean("ttt");
//		userAction.upload();
//		orderAction.upload();
		userAction.test1();
	}
}

spring(ioc)

构造器注入

UserAction.java

package com.qukang.ioc.web;

import java.util.ArrayList;
import java.util.List;

import com.qukang.ioc.biz.UserBiz;
import com.qukang.ioc.biz.UserBizImpl1;
/**
 * ioc的注入方式及各类类型
 * set注入
 * 		基本类型String
 * 		数组
 * 		自定义类型
 * 构造注入
 * 
 * 自动装配
 * 		spring4之后出现的
 * 		byType:根据配置的Bean中的接口，在spring的上下文寻找对应的实现类
 * 		byName:根据配置的Bean中的接口名字，在spring的上下文寻找对应的实现类
 * @author VULCAN
 *
 */
public class UserAction {
	private UserBiz userBiz;
	private String uname;
	private int age;
	private List<String> hobby;


	public UserAction(String uname, int age) {
		this.uname = uname;
		this.age = age;
	}
	public UserAction() {}

	public List<String> getHobby() {
		return hobby;
	}


	public void setHobby(List<String> hobby) {
		this.hobby = hobby;
	}


	public UserBiz getUserBiz() {
		return userBiz;
	}


	public void setUserBiz(UserBiz userBiz) {
		this.userBiz = userBiz;
	}


	public void upload() {
		userBiz.upload();
	}
	
	public void test1() {
		System.out.println(this.uname);
		System.out.println(this.age);
		System.out.println(this.hobby);
	}
}

spring-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:context="http://www.springframework.org/schema/context"
   xmlns:tx="http://www.springframework.org/schema/tx"
   xmlns:aop="http://www.springframework.org/schema/aop"
   xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
	<bean class="com.qukang.ioc.biz.UserBizImpl2" id="userBiz"></bean>
	<bean class="com.qukang.ioc.web.UserAction" id="xxx">
	<!-- set注入用property标签 -->
    <property name="userBiz" ref="userBiz"></property> 
		<property name="hobby">
			<list>
			<value>唱</value>
			<value>跳</value>
			<value>RAP</value>
			<value>篮球</value>
			</list>
		</property>
		<constructor-arg name="uname" value="ls"></constructor-arg>
		<constructor-arg name="age" value="22"></constructor-arg>
	</bean>
	<bean class="com.qukang.ioc.web.OrderAction" id="ttt">
<!-- 		<property name="userBiz" ref="userBiz"></property> -->
	</bean>
</beans>

IocTest.java

package com.qukang.ioc.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.qukang.ioc.web.OrderAction;
import com.qukang.ioc.web.UserAction;

public class IocTest {
	public static void main(String[] args) {		
		ApplicationContext springContext=new ClassPathXmlApplicationContext("/spring-context.xml");
		UserAction userAction =(UserAction)springContext.getBean("xxx");
		userAction.test1();
	}
}

spring(ioc)

自动装配注入

spring4之后出现的

 byType:根据配置的Bean中的接口，在spring的上下文寻找对应的实现类

 byName:根据配置的Bean中的接口名字，在spring的上下文寻找对应的实现类

UserAction.java

package com.qukang.ioc.web;

import java.util.ArrayList;
import java.util.List;

import com.qukang.ioc.biz.UserBiz;
import com.qukang.ioc.biz.UserBizImpl1;
/**
 * ioc的注入方式及各类类型
 * set注入
 * 		基本类型String
 * 		数组
 * 		自定义类型
 * 构造注入
 * 
 * 自动装配
 * 		spring4之后出现的
 * 		byType:根据配置的Bean中的接口，在spring的上下文寻找对应的实现类
 * 		byName:根据配置的Bean中的接口名字，在spring的上下文寻找对应的实现类
 * @author VULCAN
 *
 */
public class UserAction {
	private UserBiz userBiz;
	private String uname;
	private int age;
	private List<String> hobby;


	public UserAction(String uname, int age) {
		this.uname = uname;
		this.age = age;
	}
	public UserAction() {}

	public List<String> getHobby() {
		return hobby;
	}


	public void setHobby(List<String> hobby) {
		this.hobby = hobby;
	}


	public UserBiz getUserBiz() {
		return userBiz;
	}


	public void setUserBiz(UserBiz userBiz) {
		this.userBiz = userBiz;
	}


	public void upload() {
		userBiz.upload();
	}
	
	public void test1() {
		System.out.println(this.uname);
		System.out.println(this.age);
		System.out.println(this.hobby);
	}
}

spring-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   default-autowire="byType"
   xmlns:context="http://www.springframework.org/schema/context"
   xmlns:tx="http://www.springframework.org/schema/tx"
   xmlns:aop="http://www.springframework.org/schema/aop"
   xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
       http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">
	<bean class="com.qukang.ioc.biz.UserBizImpl2" id="userBiz"></bean>
	<bean class="com.qukang.ioc.web.UserAction" id="xxx">
	<!-- set注入用property标签 -->
		<property name="hobby">
			<list>
			<value>唱</value>
			<value>跳</value>
			<value>RAP</value>
			<value>篮球</value>
			</list>
		</property>
		<constructor-arg name="uname" value="ls"></constructor-arg>
		<constructor-arg name="age" value="22"></constructor-arg>
	</bean>
	<bean class="com.qukang.ioc.web.OrderAction" id="ttt">
	</bean>
</beans>

IocTest.java

package com.qukang.ioc.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.qukang.ioc.web.OrderAction;
import com.qukang.ioc.web.UserAction;

public class IocTest {
	public static void main(String[] args) {		
		ApplicationContext springContext=new ClassPathXmlApplicationContext("/spring-context.xml");
		UserAction userAction =(UserAction)springContext.getBean("xxx");
		userAction.test1();
	}
}

spring(ioc)

spring与tomcat整合

spring 作为管理整个工程中的所有的javaBean,那么如何在用户发送请求的时候能够访问到指定的javaBean呢？
处理方式:
在监听器中讲spring的上下文交给tomcat上下文中进行管理
过程:浏览器–>request–>servletContext–>springContext–>任意的javaBean

监听器
SpringLoderListener.java

 package com.qukang.ioc.listener;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
 * spring 作为管理整个工程中的所有的javaBean,那么如何在用户发送请求的时候能够访问到指定的javaBean呢？
 * 处理方式:
 * 		在监听器中 讲spring的上下文交给tomcat上下文中进行管理
 * 		浏览器-->request-->servletContext-->springContext-->任意的javaBean
 * @author VULCAN
 *
 */
@WebListener
public class SpringLoderListener implements ServletContextListener {
	@Override
	public void contextInitialized(ServletContextEvent sce) {
		System.out.println("tomcat一启动就触发了");
		ServletContext ServletContext = sce.getServletContext();
		String springXml=ServletContext.getInitParameter("springXml");
		ApplicationContext springContext=null;
		if(springXml==null || "".equals(springXml)) {
			springContext=new ClassPathXmlApplicationContext("/spring-context.xml");
		}else {
			springContext=new ClassPathXmlApplicationContext(springXml);
		}
		System.out.println("spring的上下文配置文件"+springXml);
		ServletContext.setAttribute("spring_key",springContext);
	}
}

web.xml中配置监听器

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
  <display-name>Archetype Created Web Application</display-name>
<context-param>
  	<param-name>springXml</param-name>
  	<param-value>/spring-other.xml</param-value>
  </context-param>
</web-app>

web层处理
所有的user请求
UserServlet.java

package com.qukang.ioc.web;

import java.io.IOException;

import javax.jws.WebService;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.ApplicationContext;
@WebServlet("/user")
public class UsetServlet extends HttpServlet {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(req, resp);
	}
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		// TODO Auto-generated method stub
		System.out.println("处理用户请求");
		ApplicationContext springContext=(ApplicationContext)req.getServletContext().getAttribute("spring_key");
		UserAction userAction =(UserAction)springContext.getBean("xxx");
		userAction.upload();
	}
}

spring(ioc)