spring基础（2）-注入方式和配置集合属性

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1.注入方式包括三种：属性注入，构造器注入，工厂方法。通常情况下常用的是前两种。
（1）属性注入：通过setter方法

<!--通过构造方法来配置bean的属性 -->    <bean id="car" class="com.atguigu.spring.beans.Car">    <constructor-arg value="baoma" index="0"></constructor-arg>    <constructor-arg value="qingdao" index="1"></constructor-arg>    <constructor-arg value="30000" type="double"></constructor-arg>    </bean>

（2）构造器注入

<!-- 使用构造器注入属性值可以指定参数的位置和参数的类型！ 以区分重载的构造器 -->    <bean id="car2" class="com.atguigu.spring.beans.Car">    <constructor-arg value="Audi" type="java.lang.String"></constructor-arg>    <!-- 如果字面值包含特殊字符可以使用 <![CDATA[]] 包裹起来-->    <!-- 属性值也可以用value子节点进行直接配置 -->    <constructor-arg  type="java.lang.String">        <value><![CDATA[<qingdao~>]]></value>    </constructor-arg>    <constructor-arg  type="int">        <value>250</value>    </constructor-arg>    </bean>    <bean id="person" class="com.atguigu.spring.beans.Person">        <property name="name" value="Jim" ></property>        <property name="age" value="24"></property>        <!-- 使用property的ref属性建立bean之间的引用关系 -->        <!--         <property name="car" ref="car2"></property>        <property name="car" >            <ref bean="car2"/>        </property>        -->         <!-- 内部bean  不能被外部引用 只能在内部使用 -->         <property name="car">            <bean class="com.atguigu.spring.beans.Car">                <constructor-arg value="ford"></constructor-arg>                <constructor-arg value="changan"></constructor-arg>                <constructor-arg value="20000" type="double"></constructor-arg>            </bean>         </property>    </bean>

相关的测试类

package com.atguigu.spring.beans;public class Person {    private String name;    private int age;    private Car car;    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public Car getCar() {        return car;    }    public void setCar(Car car) {        this.car = car;    }    @Override    public String toString() {        return "Person [name=" + name + ", age=" + age + ", car=" + car + "]";    }}

package com.atguigu.spring.beans;public class Car {    private String brand;    private String corp;    private double price;    private int maxSpeed;    public Car(String brand, String corp, double price) {        super();        this.brand = brand;        this.corp = corp;        this.price = price;    }    public Car(String brand, String corp, int maxSpeed) {        super();        this.brand = brand;        this.corp = corp;        this.maxSpeed = maxSpeed;    }    @Override    public String toString() {        return "Car [brand=" + brand + ", corp=" + corp + ", price=" + price + ", maxSpeed=" + maxSpeed + "]";    }}

package com.atguigu.spring.beans;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Main {    public static void main(String[] args){        /*//创建HelloWorld 的一个对象，此处的调用等同于下面的Spring调用        HelloWorld helloworld = new HelloWorld();        //为name属性赋值        helloworld.setName("atguiug");*/        //1.创建Spring 的IOC容器对象        //ApplicationContext代表IOC容器        //ClassPathXmlApplicationContext :是ApplicationContext接口的实现类，该类从类路径下加载配置文件        ApplicationContext ctx=new ClassPathXmlApplicationContext("applicationContext.xml");        //2.从IOC容器中获取bean实例        //利用id定位到IOC容器中的bean        HelloWorld helloworld = (HelloWorld) ctx.getBean("helloworld2");        //利用类型返回IOC容器中的bean，但要求IOC容器中必须只能有一个该类型的bean        //HelloWorld helloworld = ctx.getBean(HelloWorld.class);        System.out.println(helloworld);        //调用hello方法        helloworld.hello();        //通过构造方法来配置bean的属性        Car car = (Car) ctx.getBean("car");        System.out.println(car);        car = (Car) ctx.getBean("car2");        System.out.println(car);        Person person=(Person) ctx.getBean("person");        System.out.println(person);    }}

2.配置集合属性
list，Map，Properties等。
（1）spring代码

<!-- 测试如何配置集合属性 -->    <bean id="person3" class="com.atguigu.spring.beans.collection.Person">        <property name="name" value="Mike"></property>        <property name="age" value="24"></property>        <property name="cars">        <!-- 使用list节点为list类型的属性赋值 -->            <list>                <ref bean="car"></ref>                <ref bean="car2"/>            </list>        </property>    </bean>    <!-- 配置Map属性值 -->    <bean id="newPerson" class="com.atguigu.spring.beans.collection.NewPerson">        <property name="name" value="rose"></property>        <property name="age" value="28"></property>        <property name="cars">        <!-- 使用map节点及map-的entry的子节点配置map类型的成员变量 -->            <map>                <entry key="AA" value-ref="car"></entry>                <entry key="BB" value-ref="car2"></entry>            </map>        </property>    </bean>    <!-- 配置Properties属性值 -->    <bean id="dataSource" class="com.atguigu.spring.beans.collection.DataSource">        <property name="properties">        <!-- 使用props和 prop子节点为属性赋值-->            <props>                <prop key="user">root</prop>                <prop key="password">321456</prop>                <prop key="jdbcURL">jdbc://mysql</prop>                <prop key="driverClass">com.mysql.jdbc.Driver</prop>            </props>        </property>    </bean>    <!-- 配置单例的集合bean，以供多个bean进行引用，需要导入util命名空间 -->    <util:list id="cars">        <ref bean="car"/>        <ref bean="car2"/>    </util:list>    <bean id="person4" class="com.atguigu.spring.beans.collection.Person">        <property name="name" value="wangwag"></property>        <property name="age" value="29"></property>        <property name="cars" ref="cars"></property>    </bean>    <!-- 通过p命名空间为bean的属性赋值，需要先导入p命名空间 -->    <bean id="person5" class="com.atguigu.spring.beans.collection.Person" p:age="30"        p:name="rose" p:cars-ref="cars" ></bean>

（2）相关测试代码

package com.atguigu.spring.beans.collection;import java.util.List;import com.atguigu.spring.beans.Car;public class Person {    private String name;    private int age;    private List<Car> cars;    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public List<Car> getCars() {        return cars;    }    public void setCars(List<Car> cars) {        this.cars = cars;    }    @Override    public String toString() {        return "Person [name=" + name + ", age=" + age + ", cars=" + cars + "]";    }}

package com.atguigu.spring.beans.collection;import java.util.Properties;public class DataSource {    private Properties properties;    public Properties getProperties() {        return properties;    }    public void setProperties(Properties properties) {        this.properties = properties;    }    @Override    public String toString() {        return "DataSource [properties=" + properties + "]";    }}

package com.atguigu.spring.beans.collection;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Main {    public static void main(String[] args){    //创建spring的 IOC容器对象    ApplicationContext act = new ClassPathXmlApplicationContext("applicationContext.xml");    //从IOC容器中获取bean实例    Person person = (Person) act.getBean("person5");    System.out.println(person);    NewPerson  newPerson = (NewPerson) act.getBean("newPerson");    System.out.println(newPerson);    DataSource dataSource = act.getBean(DataSource.class);    System.out.println(dataSource.getProperties());    }}

package com.atguigu.spring.beans.collection;import java.util.Map;import com.atguigu.spring.beans.Car;public class NewPerson {    private String name;    private int age;    private Map<String,Car> cars;    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public int getAge() {        return age;    }    public void setAge(int age) {        this.age = age;    }    public Map<String, Car> getCars() {        return cars;    }    public void setCars(Map<String, Car> cars) {        this.cars = cars;    }    @Override    public String toString() {        return "NewPerson [name=" + name + ", age=" + age + ", cars=" + cars + "]";    }}

以上仅作为学习参考使用。

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