Spring入门

目录

1.第一个spring运行实例 

2.懒加载（lazy-init）

3.scope（包含属性有：singleton（单例，默认状态），prototype（多例），request，session）

4.init-method，destroy-method

5.属性注入

5.1 set方式注入（注入值类型（value）和引用类型（ref））

5.2 构造函数注入

5.3 复杂类型注入(array,list,set,map,properties)

6.注解配置

6.1 将对象注册到容器

6.2 注解配置-属性注入（值类型注入，引用类型注入）

7.Spring整合Junit单元测试（@RunWith(SpringJUnit4ClassRunner.class)@ContextConfiguration("classpath:applicationContext_annotation.xml")）

8.主配置文件的分包配置（） 

---

使用javaEE 

新建Dynamic Web Project（记得生成一个web.xml文件。在新建项目时别点finish，而是用两次next，勾选生成web.xml）

导入以下几个jar包 

导入spring约束文件：https://blog.youkuaiyun.com/qq_40323256/article/details/89738089

User.java:

package com.sikiedu.bean;

public class User {

	private Integer id;
	private String username;
	private String password;
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", password=" + password + "]";
	}
	
	
}

1.第一个spring运行实例 

applicationContext.xml:

<?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.xsd ">

	<bean name="user" class="com.sikiedu.bean.User"></bean>
</beans>

测试代码：HelloSpring.java:

package com.sikiedu.test;

import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.sikiedu.bean.User;

public class HelloSpring {

	@Test
	public void Test1(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
//		User u=(User) ac.getBean("user");
		User u=ac.getBean(User.class);
		System.out.println(u);
	}
}

 运行结果：

2.懒加载（lazy-init）

lazy-init="true"时表示“延迟加载”，即创建容器时不加载配置的bean对象，在bean对象被获取的时候才创建

bean对象默认会在容器创建的时候被全部加载出来，如果配置的bean较多，这对硬件的要求较高。所以此时可用延迟加载，不让他一次性加载出来，而是需要bean对象的时候才加载bean对象。

applicationContext.xml:

	<bean name="user" class="com.sikiedu.bean.User" lazy-init="true">
		<property name="id" value="1"></property>
	</bean>

3.scope（包含属性有：singleton（单例，默认状态），prototype（多例），request，session）

包含属性有：

singleton（单例，默认状态）：常用。给对象的scope属性设为singleton后，无论创建多少个这个对象，这些对象都是相同的

prototype（多例）：创建的每个对象都是不同的

request：不常用

session：不常用

4.init-method，destroy-method

User.java:

package com.sikiedu.bean;

public class User {

	private Integer id;
	private String username;
	private String password;
	
	
	public User() {
		System.out.println("空参构造方法");
		
	}
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", password=" + password + "]";
	}
	
	public void InitUser(){
		System.out.println("初始化对象");
	}
	public void DestroyUser(){
		System.out.println("对象被消除");
	}
}

applicationContext.xml:

<bean name="user" class="com.sikiedu.bean.User" lazy-init="true" scope="singleton" init-method="InitUser" destroy-method="DestroyUser">
		<property name="id" value="1"></property>
	</bean>

HelloSpring.java:

	@Test
	public void Test2(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
		
		User u1=ac.getBean(User.class);
		User u2=ac.getBean(User.class);
		User u3=ac.getBean(User.class);
		
		System.out.println(u1==u2);
		
		//关闭容器对象ac，就会触发bean的destroymethod
		ac.close();
	}

运行结果：

5.属性注入

5.1 set方式注入（注入值类型（value）和引用类型（ref））

Pet.java:

package com.sikiedu.bean;

public class Pet {

	private String petType;
	private String color;
	
	public String getPetType() {
		return petType;
	}
	public void setPetType(String petType) {
		this.petType = petType;
	}
	public String getColor() {
		return color;
	}
	public void setColor(String color) {
		this.color = color;
	}
	@Override
	public String toString() {
		return "Pet [petType=" + petType + ", color=" + color + "]";
	}
}

User.java:

package com.sikiedu.bean;

public class User {

	private Integer id;
	private String username;
	private String password;
	private Pet pet;
	
	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public Pet getPet() {
		return pet;
	}
	public void setPet(Pet pet) {
		this.pet = pet;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", password=" + password + ", pet=" + pet + "]";
	}
	

}

applicationContext.xml:

<?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.xsd ">

	<bean name="user" class="com.sikiedu.bean.User">
		<property name="id" value="1"></property>
		<property name="username" value="王五"></property>
		<property name="password" value="555"></property>
		
		<property name="pet" ref="pet"></property>
	</bean>
	
	<bean name="pet" class="com.sikiedu.bean.Pet">
		<property name="petType" value="二哈"></property>
		<property name="color" value="灰色"></property>
	</bean>
</beans>

HelloSpring.java:

package com.sikiedu.test;

import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.sikiedu.bean.User;

public class HelloSpring {

	@Test
	public void Test1(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
		User u=ac.getBean(User.class);
		System.out.println(u);
	}
	
}

运行结果：

5.2 构造函数注入

User.java:

package com.sikiedu.bean;

public class User {

	private Integer id;
	private String username;
	private String password;
	private Pet pet;
	
	
	public User() {
		System.out.println("这是无参构造函数。在使用含参构造函数之前，必须先要写无参构造函数");
	}

	public User(String username, Pet pet) {
		System.out.println("这是含参构造函数。方法1：String,Pet");
		this.username = username;
		this.pet = pet;
	}
	public User(Integer id, Pet pet) {
		System.out.println("这是含参构造函数。方法2：Integer,Pet");
		this.id = id;
		this.pet = pet;
	}
	public User(Pet pet,Integer id) {
		System.out.println("这是含参构造函数。方法3：Pet,Integer");
		this.id = id;
		this.pet = pet;
	}

	public Integer getId() {
		return id;
	}
	public void setId(Integer id) {
		this.id = id;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public Pet getPet() {
		return pet;
	}
	public void setPet(Pet pet) {
		this.pet = pet;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", password=" + password + ", pet=" + pet + "]";
	}
	

}

applicationContext.xml:

	<bean name="pet" class="com.sikiedu.bean.Pet">
		<property name="petType" value="二哈"></property>
		<property name="color" value="灰色"></property>
	</bean>
	
<!-- 	构造方法注入 -->
<!-- 	type:指定参数类型 -->
<!-- 	index：指定参数索引 -->
	<bean name="user1" class="com.sikiedu.bean.User">
		<constructor-arg name="id" value="6" type="java.lang.Integer" index="0"></constructor-arg>
		<constructor-arg name="pet" ref="pet"></constructor-arg>
	</bean>

HelloSpring.java:

	@Test
	public void Test2(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
		User u=(User) ac.getBean("user1");
		System.out.println(u);
	}

运行结果：

5.3 复杂类型注入(array,list,set,map,properties)

MyCollection.java:

package com.sikiedu.bean;

import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

public class MyCollection {

	private Object[] array;
	private List list;
	private Set set;
	private Map map;
	private Properties properties;
	
	public Object[] getArray() {
		return array;
	}
	public void setArray(Object[] array) {
		this.array = array;
	}
	public List getList() {
		return list;
	}
	public void setList(List list) {
		this.list = list;
	}
	public Set getSet() {
		return set;
	}
	public void setSet(Set set) {
		this.set = set;
	}
	
	public Map getMap() {
		return map;
	}
	public void setMap(Map map) {
		this.map = map;
	}
	public Properties getProperties() {
		return properties;
	}
	public void setProperties(Properties properties) {
		this.properties = properties;
	}
	
	@Override
	public String toString() {
		return "MyCollection [array=" + Arrays.toString(array) + ", list=" + list + ", set=" + set + ", map=" + map
				+ ", properties=" + properties + "]";
	}
}

 applicationContext.xml:

<?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.xsd ">

	<bean name="user" class="com.sikiedu.bean.User">
		<property name="id" value="1"></property>
		<property name="username" value="王五"></property>
		<property name="password" value="555"></property>
		
		<property name="pet" ref="pet"></property>
	</bean>
	
	<bean name="pet" class="com.sikiedu.bean.Pet">
		<property name="petType" value="二哈"></property>
		<property name="color" value="灰色"></property>
	</bean>
	
<!-- 	构造方法注入 -->
<!-- 	type:指定参数类型 -->
<!-- 	index：指定参数索引 -->
	<bean name="user1" class="com.sikiedu.bean.User">
		<constructor-arg name="id" value="6" type="java.lang.Integer" index="0"></constructor-arg>
		<constructor-arg name="pet" ref="pet"></constructor-arg>
	</bean>
	
<!-- 	复杂类型注入 -->
	<bean name="myCollection" class="com.sikiedu.bean.MyCollection">
		<property name="array">
			<array>
				<value>111</value>
				<value>aaa</value>
				<ref bean="user"/>
			</array>
		</property>
		
		<property name="list">
			<list>
				<value>222</value>
				<value>bbb</value>
				<ref bean="user"/>
			</list>
		</property>
		
		<property name="set">
			<set>
				<value>333</value>
				<value>ccc</value>
				<ref bean="user"/>
			</set>
		</property>
		
		<property name="map">
			<map>
				<entry key="username" value="root"></entry>
				<entry key="password" value="root"></entry>
				<entry key-ref="user" value-ref="pet"></entry>
			</map>
		</property>
		
		<property name="properties">
			<props>
				<prop key="name">老李</prop>
				<prop key="age">25</prop>
			</props>
		</property>
	</bean>
</beans>

HelloSpring.java:

	@Test
	public void Test3(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
		MyCollection mc = (MyCollection) ac.getBean("myCollection");
		System.out.println(mc);
	}

运行结果：

6.注解配置

6.1 将对象注册到容器

<bean name="user2" class="com.sikiedu.bean.User2">
@Component("user2")         //不够精细，因为里面太杂了，什么都有

以后常用的是下面这种，因为分的更细

@Controller()        //对应web层
@Service()           //对应service层
@Repository()     //对应dao层

导入aop包

配置约束

如果已经装了springIDE插件，只需要

如果没有按照springIde插件，添加约束方式参考：https://blog.youkuaiyun.com/qq_40323256/article/details/89738089

如果需要按照springIDE插件，安装视频教程：http://www.sikiedu.com/course/267/task/13547/show

User2.java：

package com.sikiedu.bean;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

import org.springframework.stereotype.Service;

//<bean name="user2" class="com.sikiedu.bean.User2">
//@Component("user2") //不够精细，因为里面太杂了，什么都有

//@Controller()  //对应web层
//@Service() //对应service层
//@Repository()  //对应dao层

@Service("user2")
public class User2 {

	private Integer id;
	private String username;
	private String password;

	public User2() {
		System.out.println("这是无参构造函数。在使用含参构造函数之前，必须先要写无参构造函数");
	}

	public Integer getId() {
		return id;
	}

	public void setId(Integer id) {
		this.id = id;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	@Override
	public String toString() {
		return "User2 [id=" + id + ", username=" + username + ", password=" + password + "]";
	}
	
	@PostConstruct()
	public void initUser2(){
		System.out.println("init User2");
	}
	
	@PreDestroy()
	public void destroyUser2(){
		System.out.println("destroy User2");
	}

}

applicationContext_annotation.xml：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">
		
<!-- 注解开发 -->
<!-- 	开启注解扫描，base-package扫描该包及子包的所有注解 -->
	<context:component-scan base-package="com.sikiedu.bean"></context:component-scan>
</beans>

HelloSpring.java:

	@Test
	public void Test4(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext_annotation.xml");
		User2 u2= (User2) ac.getBean("user2");
		System.out.println(u2);
	}

运行结果：

6.2 注解配置-属性注入（值类型注入，引用类型注入）

值类型注入：@Value（“”）

引用类型注入：   @Autowired()                        //自动装配。不推荐
                             @Resource(name="")     //手动装配。推荐

Pet.java:

package com.sikiedu.bean;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component("pet")
public class Pet {

	private String petType;
	private String color;
	
	public String getPetType() {
		return petType;
	}
	
	@Value("金毛")
	public void setPetType(String petType) {
		this.petType = petType;
	}
	public String getColor() {
		return color;
	}
	
	@Value("黄色")
	public void setColor(String color) {
		this.color = color;
	}
	@Override
	public String toString() {
		return "Pet [petType=" + petType + ", color=" + color + "]";
	}
}

User2.java:

package com.sikiedu.bean;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.annotation.Resource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

//<bean name="user2" class="com.sikiedu.bean.User2">
//@Component("user2") //不够精细，因为里面太杂了，什么都有

//@Controller()  //对应web层
//@Service() //对应service层
//@Repository()  //对应dao层

@Service("user2")
public class User2 {

	private Integer id;
	private String username;
	private String password;
	private Pet pet;

	public User2() {
		System.out.println("这是无参构造函数。在使用含参构造函数之前，必须先要写无参构造函数");
	}

	public Integer getId() {
		return id;
	}

	@Value("2")
	public void setId(Integer id) {
		this.id = id;
	}

	public String getUsername() {
		return username;
	}

	@Value("李疆疆")
	public void setUsername(String username) {
		this.username = username;
	}

	public String getPassword() {
		return password;
	}

	@Value("2333")
	public void setPassword(String password) {
		this.password = password;
	}
	
	public Pet getPet() {
		return pet;
	}

//	@Autowired() //自动装配。不推荐
	@Resource(name="pet") //手动装配。推荐
	public void setPet(Pet pet) {
		this.pet = pet;
	}

	@PostConstruct()
	public void initUser2(){
		System.out.println("init User2");
	}
	
	@PreDestroy()
	public void destroyUser2(){
		System.out.println("destroy User2");
	}

	@Override
	public String toString() {
		return "User2 [id=" + id + ", username=" + username + ", password=" + password + ", pet=" + pet + "]";
	}

	
}

HelloSpring.java:

	@Test
	public void Test4(){
		ClassPathXmlApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext_annotation.xml");
		User2 u2= (User2) ac.getBean("user2");
		System.out.println(u2);
	}

运行结果：

7.Spring整合Junit单元测试（@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext_annotation.xml")）

导入test包

Pet.java:

package com.sikiedu.bean;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component("pet")
public class Pet {

	private String petType;
	private String color;
	
	public String getPetType() {
		return petType;
	}
	
	@Value("金毛")
	public void setPetType(String petType) {
		this.petType = petType;
	}
	public String getColor() {
		return color;
	}
	
	@Value("黄色")
	public void setColor(String color) {
		this.color = color;
	}
	@Override
	public String toString() {
		return "Pet [petType=" + petType + ", color=" + color + "]";
	}
}

applicationContext_annotation.xml：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">
		
<!-- 注解开发 -->
<!-- 	开启注解扫描，base-package扫描该包及子包的所有注解 -->
	<context:component-scan base-package="com.sikiedu.bean"></context:component-scan>
	
</beans>

test.java:

package com.sikiedu.test;

import javax.annotation.Resource;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.sikiedu.bean.Pet;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext_annotation.xml")
public class test {

	@Resource(name="pet")
	private Pet pet;
	
	@Test
	public void Test(){
		System.out.println(pet);
	}
}

 运行结果：

8.主配置文件的分包配置（<import resource="xxx.xml"/>） 

Pet.java:

package com.sikiedu.bean;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component("pet")
public class Pet {

	private String petType;
	private String color;
	
	public String getPetType() {
		return petType;
	}
	
	@Value("金毛")
	public void setPetType(String petType) {
		this.petType = petType;
	}
	public String getColor() {
		return color;
	}
	
	@Value("黄色")
	public void setColor(String color) {
		this.color = color;
	}
	@Override
	public String toString() {
		return "Pet [petType=" + petType + ", color=" + color + "]";
	}
}

applicationContext_test.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">

<import resource="applicationContext_annotation.xml"/>

</beans>

applicationContext_annotation.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">
		
<!-- 注解开发 -->
<!-- 	开启注解扫描，base-package扫描该包及子包的所有注解 -->
	<context:component-scan base-package="com.sikiedu.bean"></context:component-scan>
	
</beans>

test.java:

package com.sikiedu.test;

import javax.annotation.Resource;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import com.sikiedu.bean.Pet;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext_test.xml")
public class test {

	@Resource(name="pet")
	private Pet pet;
	
	@Test
	public void Test(){
		System.out.println(pet);
	}
}

运行结果：