一. 通过XML配置装配的方式
1.XML自动装配（不推荐）
2.Setter注入
3.构造器注入
4.bean元素继承
5.Property place holder
6.注册案例
代码演示
（1）XML自动装配（不推荐）
使用autowire modes:no ,default, byName,byType,constructor
<?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 = "dog" class = "com.keen.xml_auto.Dog"/>
<bean id = "person" class ="com.keen.xml_auto.Person" autowire="byName"/>
</beans>
(2)Setter注入（常用）
1.简单类型（常量值）注入
使用property，name ，value；
<?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 = "employee" class ="com.keen.xml.setter.Employee">
<property name="name" value = "keen"/>
<property name="age" value = "23"/>
<property name="salary" value = "6666"/>
</bean>
</beans>
Employee类
package com.keen.xml.setter;
public class Employee {
private String name;
private int age;
private double salary;
public void setName(String name) {
this.name = name;
}
public void setAge(int age) {
this.age = age;
}
public void setSalary(double salary) {
this.salary = salary;
}
@Override
public String toString() {
return "Employee [name=" + name + ", age=" + age + ", salary=" + salary + "]";
}
}
2.对象类型注入(使用property 的ref 关联对象）
<!-- 属性注入：对象类型 -->
<bean id = "cat1" class = "com.keen.xml.setter.Cat"/>
<bean id = "person" class ="com.keen.xml.setter.Person">
<property name="cat" ref = "cat1"/>
</bean>
⚠️<!-- ref = "cat1" 与 bean id = “cat1”要一致 -->
3.集合类型注入(使用对应集合元素<set> ,list>, <map>...）
<!--属性注入： 集合类型 -->
<bean id = "collectionbean1" class = "com.keen.xml.setter.CollectionBean1">
<!-- set配置 -->
<property name="set">
<set>
<value>set1</value>
<value>set2</value>
</set>
</property>
<!-- list配置 -->
<property name="list">
<list>
<value>list1</value>
<value>list2</value>
</list>
</property>
<!-- array配置 -->
<property name="array">
<array>
<value>array1</value>
<value>array2</value>
</array>
</property>
<!-- map配置 -->
<property name="map">
<map>
<entry key="key1" value = "value1"/>
<entry key="key2" value = "value2"/>
</map>
</property>
<!--1 properties设置 -->
<!-- <property name="prop">
<props>
<prop key="p1">v1</prop>
<prop key="p2">v2</prop>
</props>
</property> -->
<!-- 2 properties设置(比较简单，比较常用） -->
<property name="prop">
<value>
p1 = v1;
p2 = v2;
p3 = v3;
</value>
</property>
</bean>
CollectionBean1类
package com.keen.xml.setter;
import java.util.*;
public class CollectionBean1 {
private Set<String> set;
private List<String> list;
private String[] array ;
private Map<String,String> map;
private Properties prop;
public void setArray(String[] array) {
this.array = array;
}
public void setMap(Map<String, String> map) {
this.map = map;
}
public void setProp(Properties prop) {
this.prop = prop;
}
public void setSet(Set<String> set) {
this.set = set;
}
public void setList(List<String> list) {
this.list = list;
}
@Override
public String toString() {
return "CollectionBean1 [set=" + set + ", list=" + list + ", array=" + Arrays.toString(array) + ", map=" + map
+ ", prop=" + prop + "]";
}
}
(3)构造器注入（了解）
<1>常量类型注入
<!-- 构造器注入：常量类型 -->
<bean id = "employee" class = "com.keen.xml.constructor.Employee1">
<constructor-arg name = "name" value = "keen"/>
<constructor-arg name = "age" value = "age"/>
<constructor-arg name = "salary" value = "6666"/>
</bean>
Employee1类
public class Employee1 {
private String name;
private int age;
private double salary;
public Employee1(String name, int age, double salary) {
super();
this.name = name;
this.age = age;
this.salary = salary;
}
@Override
public String toString() {
return "Employee [name=" + name + ", age=" + age + ", salary=" + salary + "]";
}
}
<2>对象类型注入(了解）
<!-- 构造器注入：对象类型 -->
<bean id = "cat" class = "com.keen.xml.constructor.Cat1"/>
<bean id = "person" class = "com.keen.xml.constructor.Person1">
<constructor-arg name = "cat1" ref = "cat"></constructor-arg>
</bean>
人类
package com.keen.xml.constructor;
public class Person1 {
private Cat1 cat1;
public Person1(Cat1 cat1) {
super();
this.cat1 = cat1;
}
@Override
public String toString() {
return "Person [cat=" + cat1 + "]";
}
}
猫类
package com.keen.xml.constructor;
public class Cat1 {
}
<3>集合类型注入：
（1）将seeter注入的集合注入类型中的property改为constructor-arg即可
（2）将employee的setter方法改为带参数构造器即可
<!--构造器注入： 集合类型 -->
<bean id = "collectionbean2" class = "com.keen.xml.constructor.CollectionBean2">
<!-- set配置 -->
<constructor-arg name="set">
<set>
<value>set1</value>
<value>set2</value>
</set>
</constructor-arg>
<!-- list配置 -->
<constructor-arg name="list">
<list>
<value>list1</value>
<value>list2</value>
</list>
</constructor-arg>
<!-- array配置 -->
<constructor-arg name="array">
<array>
<value>array1</value>
<value>array2</value>
</array>
</constructor-arg>
<!-- map配置 -->
<constructor-arg name="map">
<map>
<entry key="key1" value = "value1"/>
<entry key="key2" value = "value2"/>
</map>
</constructor-arg>
<!--1 properties设置 -->
<!-- <constructor-arg name="prop">
<props>
<prop key="p1">v1</prop>
<prop key="p2">v2</prop>
</props>
</constructor-arg> -->
<!-- 2 properties设置(比较简单，比较常用） -->
<constructor-arg name="prop">
<value>
p1 = v1;
p2 = v2;
p3 = v3;
</value>
</constructor-arg>
</bean>
添加：内部bean，外面无法访问
<!-- 内部bean -->
<bean id = "person" class = "com.keen.xml.constructor.Person1">
<constructor-arg name = "cat1" >
<bean class ="com.keen.xml.constructor.Cat1"/>
</constructor-arg>
<!-- 此时 cat1 仅服务于 person-->
（4）bean元素的继承
多个bean元素的共同配置部分的抽取，和Java的继承不同
Java继承：把多个类共同的代码抽取到父类中
bean元素的继承（inheritance）：把多个bean元素共同的属性配置抽取到另外一个公用的bean元素中。
xml原本的配置
<bean id = "somebean1" class = "com.keen.bean.inheitance.Somebean1">
<property name="name" value = "keen"/>
<property name="age" value = "18"/>
<property name="height" value = "160"/>
</bean>
<bean id = "somebean2" class = "com.keen.bean.inheitance.Somebean2">
<property name="name" value = "keen"/>
<property name="age" value = "18"/>
<property name="weight" value = "45"/>
</bean>
bean元素的继承后配置
<!-- bean元素的继承 -->
<bean id ="base" abstract="true">
<property name="name" value = "keen"/>
<property name="age" value = "18"/>
</bean>
<!-- 配置somebean1 -->
<bean id = "somebean1" class = "com.keen.bean.inheitance.Somebean1" parent="base">
<property name="height" value = "160"/>
</bean>
<!-- 配置somebean2 -->
<bean id = "somebean2" class = "com.keen.bean.inheitance.Somebean2" parent="base">
<property name="weight" value = "45"/>
</bean>
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