SSM-Spring-04：Spring的DI的构造注入，P命名注入，和集合注入

------------吾亦无他,唯手熟尔，谦卑若愚，好学若饥-------------

DI和IOC相比，DI更偏向于实现

DI的set方式注入在前面入门案例里有写，所以此处不多啰嗦，直接开搞，先说构造注入和P命名注入

　　　　构造方式，理所当然要有带参构造，这儿值得注意的是，你最好再补全一个无参构造，因为你写了带参构造，系统就不再会为你默认补全一个无参构造了，当你在不经意或者不知情的情况下被调用了，就会报错

　　　　P命名则有注意的是那个头文件 xmlns　　xsi需要你去配置一道，我下面有，你直接copy就可以

　　　　在实体类中（有俩个实体类，我做了关联关系）

package cn.dawn.day05diup;

/**

 * Created by Dawn on 2018/3/5.

 */

public class Car {

    private String color;

    private String type;

    public String getColor() {

        return color;

    }

    public void setColor(String color) {

        this.color = color;

    }

    public String getType() {

        return type;

    }

    public void setType(String type) {

        this.type = type;

    }

}

package cn.dawn.day05diup;

/**

 * Created by Dawn on 2018/3/5.

 */

//student类

public class Student {

    private String name;

    private Integer age;

    private Car car;

    //带参构造

    public Student(String name, Integer age, Car car) {

        this.name = name;

        this.age = age;

        this.car = car;

    }

    //无参构造

    public Student() {

    }

    public String getName() {

        return name;

    }

    public void setName(String name) {

        this.name = name;

    }

    public Integer getAge() {

        return age;

    }

    public void setAge(Integer age) {

        this.age = age;

    }

    public Car getCar() {

        return car;

    }

    public void setCar(Car car) {

        this.car = car;

    }

}

　　　　在大配置xml文件中

<?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:p="http://www.springframework.org/schema/p"

       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd ">

    <bean id="car" class="cn.dawn.day05diup.Car">

        <property name="color" value="黑色"></property>

        <property name="type" value="奥迪"></property>

    </bean>

    <!--di构造注入-->

    <!--<bean id="student" class="cn.dawn.day05diup.Student">

        <constructor-arg index="" value="孟六"></constructor-arg>

        <constructor-arg index="" value=""></constructor-arg>

        <constructor-arg index="" ref="car"></constructor-arg>

    </bean>-->

    <!--p命名注入-->

    <bean id="student" class="cn.dawn.day05diup.Student" p:name="孟小六" p:age="" p:car-ref="car"></bean>

</beans>

　　　　没有什么好讲的，带参构造的注入方法，index索引从0开始，对应的是那个带参构造的index

　　　　单测方法：

    @Test

    /*diP命名注入*/

    public void t02(){

        ApplicationContext context=new ClassPathXmlApplicationContext("ApplicationContext-day05diup.xml");

        Student student = (Student) context.getBean("student");

        System.out.println("学生"+student.getName()+"开着"+student.getCar().getColor()+"的"+student.getCar().getType());

    }

    @Test

    /*di构造注入*/

    public void t01(){

        ApplicationContext context=new ClassPathXmlApplicationContext("ApplicationContext-day05diup.xml");

        Student student = (Student) context.getBean("student");

        System.out.println("学生"+student.getName()+"开着"+student.getCar().getColor()+"的"+student.getCar().getType());

    }

集合注入：

　　　　数组，List，Set，Map，Properties

　　实体类

package cn.dawn.day05diup;

import java.util.*;

/**

 * Created by Dawn on 2018/3/5.

 */

public class MyCollection {

    private String[] array;

    private List<String> list;

    private Set<String> set;

    private Map<String,String> map;

    private Properties properties;

    @Override

    public String toString() {

        return "MyCollection{" +

                "array=" + Arrays.toString(array) +

                ", list=" + list +

                ", set=" + set +

                ", map=" + map +

                ", properties=" + properties +

                '}';

    }

    public String[] getArray() {

        return array;

    }

    public void setArray(String[] array) {

        this.array = array;

    }

    public List<String> getList() {

        return list;

    }

    public void setList(List<String> list) {

        this.list = list;

    }

    public Set<String> getSet() {

        return set;

    }

    public void setSet(Set<String> set) {

        this.set = set;

    }

    public Map<String, String> getMap() {

        return map;

    }

    public void setMap(Map<String, String> map) {

        this.map = map;

    }

    public Properties getProperties() {

        return properties;

    }

    public void setProperties(Properties properties) {

        this.properties = properties;

    }

}

　　大配置中的bean节点

<!--di的集合注入-->

    <bean id="mycollection" class="cn.dawn.day05diup.MyCollection">

        <!--数组注入-->

        <property name="array">

            <array>

                <value>孟六</value>

                <value>孟六十六</value>

                <value>孟六百六十六</value>

            </array>

        </property>

        <!--list集合注入-->

        <property name="list">

            <list>

                <value>奥迪</value>

                <value>奥小迪</value>

                <value>奥迪迪</value>

            </list>

        </property>

        <!--set集合注入-->

        <property name="set">

            <set>

                <value>set1</value>

                <value>set2</value>

                <value>set3</value>

            </set>

        </property>

        <!--map集合注入-->

        <property name="map">

            <map>

                <entry key="姓名">

                    <value>孟五</value>

                </entry>

                <entry key="年龄">

                    <value></value>

                </entry>

            </map>

        </property>

        <!--properties-->

        <property name="properties">

            <props>

                <prop key="key1">v1</prop>

                <prop key="key2">v2</prop>

                <prop key="key3">v3</prop>

            </props>

        </property>

    </bean>

　　　　单测

    @Test

    /*di集合注入*/

    public void t03(){

        ApplicationContext context=new ClassPathXmlApplicationContext("ApplicationContext-day05diup.xml");

        MyCollection mycollection = (MyCollection) context.getBean("mycollection");

        System.out.println(mycollection);

    }

　　　　由于重写了toString，可以直接一览无余

巴特西

SSM-Spring-04：Spring的DI的构造注入，P命名注入，和集合注入

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