spring基础（2）-注入方式和配置集合属性

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。