spring5(6) -DI 通过xml配置装配 -1

作者: 小白201808 | 来源:发表于2018-09-18 18:49 被阅读30次

spring5(6) -DI 通过xml配置装配 -1
spring5(6) -DI 通过xml配置装配 -2
Bean转配
Spring bean 自动装配、抽象、作用域、依赖、继承、使用
spring梳理（一）bean装配方式介绍
05 装配bean
Hbase Java API 使用
02_Spring_注解装配bean&AOP编程
Spring 装配Bean
终极搞一波

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>