Spring入门第五课

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集合属性

在Spring中可以通过一组内置的xml标签(如:<list>,<set>,<map>)来配置集合属性。

配置java.util.List类型的属性,需要制定<list>标签,在标签里面包含一些元素,这些标签可以通过<value>指定简单的常量值,通过<ref>指定对其他Bean的引用,通过<bean>指定内置Bean定义,通过<null/>指定空值。甚至可以内嵌其他集合。

数组的定义和List一样,都是用<list>

配置Java.util.Set需要使用<set>标签,定义元素的方法和List一样。

看如何配置List

<?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">
    
    <!-- 配置bean
    class:bean的全类名,通过反射的方式在IOC容器中创建bean,所以要求Bean中必须有无参的构造函数
    id:表示容器的bean,id唯一 -->
    <bean id="hello" class="logan.spring.study.HelloWorld">
    </bean>
    
    <bean id="hello2" class="logan.spring.study.HelloWorld">
    </bean>
    
    <!-- 通过构造方法来配置Bean的属性 -->
    <bean id="car" class="logan.spring.study.Car">
        <constructor-arg value="Audi" index="0"></constructor-arg>
        <constructor-arg value="Shanghai" index="1"></constructor-arg>
        <constructor-arg value="3000000" index="2" type="double"></constructor-arg>
    </bean>
    <bean id="car2" class="logan.spring.study.Car">
        <constructor-arg value="Baoma" type="java.lang.String"></constructor-arg>
        <constructor-arg type="java.lang.String">
            <value><![CDATA[<Shanghai>]]></value>
        </constructor-arg>
        <constructor-arg type="int">
            <value>250</value>
        </constructor-arg>
    </bean>
    
    <bean id="person" class="logan.spring.study.Person">
        <property name="name" value="Tom"></property>
        <property name="age" value="24"></property>
        <property name="car">
            <bean class="logan.spring.study.Car">
                <constructor-arg value="Ford"></constructor-arg>
                <constructor-arg value="Changan"></constructor-arg>
                <constructor-arg value="20000000" type="double"></constructor-arg>
            </bean>
        </property>
    </bean>
    
    <bean id="person2" class="logan.spring.study.Person">
        <constructor-arg value="Jerry"></constructor-arg>
        <constructor-arg value="25"></constructor-arg>
        <!-- 
        <constructor-arg ref="car"></constructor-arg>
        
        <constructor-arg><null/></constructor-arg>
        -->
        <constructor-arg ref="car"></constructor-arg>
        <property name="car.maxspeed" value="250"></property>
    </bean>
    <bean id="person3" class="logan.spring.study.collections.Person">
        <property name="name" value="Mike"></property>
        <property name="age" value="27"></property>
        <property name="cars">
            <list>
                <ref bean="car"/>
                <ref bean="car2"/>
            </list>
        </property>
    </bean>

</beans>

下面是输出结果:

五月 19, 2017 9:55:58 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]3eb07fd3: startup date [Fri May 19 21:55:58 CST 2017]; root of context hierarchy
五月 19, 2017 9:55:58 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
HelloWorld‘s Constructor...
HelloWorld‘s Constructor...
Person [name=Mike, age=27, cars=[Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]]]

下面看如何配置map

<?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">
    
    <!-- 配置bean
    class:bean的全类名,通过反射的方式在IOC容器中创建bean,所以要求Bean中必须有无参的构造函数
    id:表示容器的bean,id唯一 -->
    <bean id="hello" class="logan.spring.study.HelloWorld">
    </bean>
    
    <bean id="hello2" class="logan.spring.study.HelloWorld">
    </bean>
    
    <!-- 通过构造方法来配置Bean的属性 -->
    <bean id="car" class="logan.spring.study.Car">
        <constructor-arg value="Audi" index="0"></constructor-arg>
        <constructor-arg value="Shanghai" index="1"></constructor-arg>
        <constructor-arg value="3000000" index="2" type="double"></constructor-arg>
    </bean>
    <bean id="car2" class="logan.spring.study.Car">
        <constructor-arg value="Baoma" type="java.lang.String"></constructor-arg>
        <constructor-arg type="java.lang.String">
            <value><![CDATA[<Shanghai>]]></value>
        </constructor-arg>
        <constructor-arg type="int">
            <value>250</value>
        </constructor-arg>
    </bean>
    
    <bean id="person" class="logan.spring.study.Person">
        <property name="name" value="Tom"></property>
        <property name="age" value="24"></property>
        <property name="car">
            <bean class="logan.spring.study.Car">
                <constructor-arg value="Ford"></constructor-arg>
                <constructor-arg value="Changan"></constructor-arg>
                <constructor-arg value="20000000" type="double"></constructor-arg>
            </bean>
        </property>
    </bean>
    
    <bean id="person2" class="logan.spring.study.Person">
        <constructor-arg value="Jerry"></constructor-arg>
        <constructor-arg value="25"></constructor-arg>
        <!-- 
        <constructor-arg ref="car"></constructor-arg>
        
        <constructor-arg><null/></constructor-arg>
        -->
        <constructor-arg ref="car"></constructor-arg>
        <property name="car.maxspeed" value="250"></property>
    </bean>
    <bean id="person3" class="logan.spring.study.collections.Person">
        <property name="name" value="Mike"></property>
        <property name="age" value="27"></property>
        <property name="cars">
            <list>
                <ref bean="car"/>
                <ref bean="car2"/>
            </list>
        </property>
    </bean>
    <bean id="newPerson" class="logan.spring.study.collections.NewPerson">
        <property name="name" value="Rose"></property>
        <property name="age" value="28"></property>
        <property name="car">
            <map>
                <entry key="AA" value-ref="car"></entry>
                <entry key="BB" value-ref="car2"></entry>
            </map>
        </property>
    </bean>

</beans>

下面是输出结果:

五月 19, 2017 10:07:29 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]3eb07fd3: startup date [Fri May 19 22:07:29 CST 2017]; root of context hierarchy
五月 19, 2017 10:07:29 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
HelloWorld‘s Constructor...
HelloWorld‘s Constructor...
NewPerson [name=Rose, age=28, car={AA=Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], BB=Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]}]

下面看如何设置properties

<?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">
    
    <!-- 配置bean
    class:bean的全类名,通过反射的方式在IOC容器中创建bean,所以要求Bean中必须有无参的构造函数
    id:表示容器的bean,id唯一 -->
    <bean id="hello" class="logan.spring.study.HelloWorld">
    </bean>
    
    <bean id="hello2" class="logan.spring.study.HelloWorld">
    </bean>
    
    <!-- 通过构造方法来配置Bean的属性 -->
    <bean id="car" class="logan.spring.study.Car">
        <constructor-arg value="Audi" index="0"></constructor-arg>
        <constructor-arg value="Shanghai" index="1"></constructor-arg>
        <constructor-arg value="3000000" index="2" type="double"></constructor-arg>
    </bean>
    <bean id="car2" class="logan.spring.study.Car">
        <constructor-arg value="Baoma" type="java.lang.String"></constructor-arg>
        <constructor-arg type="java.lang.String">
            <value><![CDATA[<Shanghai>]]></value>
        </constructor-arg>
        <constructor-arg type="int">
            <value>250</value>
        </constructor-arg>
    </bean>
    
    <bean id="person" class="logan.spring.study.Person">
        <property name="name" value="Tom"></property>
        <property name="age" value="24"></property>
        <property name="car">
            <bean class="logan.spring.study.Car">
                <constructor-arg value="Ford"></constructor-arg>
                <constructor-arg value="Changan"></constructor-arg>
                <constructor-arg value="20000000" type="double"></constructor-arg>
            </bean>
        </property>
    </bean>
    
    <bean id="person2" class="logan.spring.study.Person">
        <constructor-arg value="Jerry"></constructor-arg>
        <constructor-arg value="25"></constructor-arg>
        <!-- 
        <constructor-arg ref="car"></constructor-arg>
        
        <constructor-arg><null/></constructor-arg>
        -->
        <constructor-arg ref="car"></constructor-arg>
        <property name="car.maxspeed" value="250"></property>
    </bean>
    <bean id="person3" class="logan.spring.study.collections.Person">
        <property name="name" value="Mike"></property>
        <property name="age" value="27"></property>
        <property name="cars">
            <list>
                <ref bean="car"/>
                <ref bean="car2"/>
            </list>
        </property>
    </bean>
    <bean id="newPerson" class="logan.spring.study.collections.NewPerson">
        <property name="name" value="Rose"></property>
        <property name="age" value="28"></property>
        <property name="car">
            <map>
                <entry key="AA" value-ref="car"></entry>
                <entry key="BB" value-ref="car2"></entry>
            </map>
        </property>
    </bean>
    
    <bean id="dataSource" class="logan.spring.study.collections.DataSource">
        <property name="properties">
            <props>
                <prop key="user">root</prop>
                <prop key="password">1234</prop>
                <prop key="jdbcUrl">jdbc:mysql://test</prop>
                <prop key="driverClass">com.mysql.jdbc.Driver</prop>
            </props>
        </property>
    </bean>

</beans>

下面是输出结果

五月 19, 2017 10:17:59 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]3eb07fd3: startup date [Fri May 19 22:17:59 CST 2017]; root of context hierarchy
五月 19, 2017 10:17:59 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
HelloWorld‘s Constructor...
HelloWorld‘s Constructor...
NewPerson [name=Rose, age=28, car={AA=Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], BB=Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]}]
DataSource [properties={driverClass=com.mysql.jdbc.Driver, user=root, password=1234, jdbcUrl=jdbc:mysql://test}]

如何把集合的配置独立出来

看如下代码,这里需要导入util命名空间

<?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:util="http://www.springframework.org/schema/util"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
    
    <!-- 配置bean
    class:bean的全类名,通过反射的方式在IOC容器中创建bean,所以要求Bean中必须有无参的构造函数
    id:表示容器的bean,id唯一 -->
    <bean id="hello" class="logan.spring.study.HelloWorld">
    </bean>
    
    <bean id="hello2" class="logan.spring.study.HelloWorld">
    </bean>
    
    <!-- 通过构造方法来配置Bean的属性 -->
    <bean id="car" class="logan.spring.study.Car">
        <constructor-arg value="Audi" index="0"></constructor-arg>
        <constructor-arg value="Shanghai" index="1"></constructor-arg>
        <constructor-arg value="3000000" index="2" type="double"></constructor-arg>
    </bean>
    <bean id="car2" class="logan.spring.study.Car">
        <constructor-arg value="Baoma" type="java.lang.String"></constructor-arg>
        <constructor-arg type="java.lang.String">
            <value><![CDATA[<Shanghai>]]></value>
        </constructor-arg>
        <constructor-arg type="int">
            <value>250</value>
        </constructor-arg>
    </bean>
    
    <bean id="person" class="logan.spring.study.Person">
        <property name="name" value="Tom"></property>
        <property name="age" value="24"></property>
        <property name="car">
            <bean class="logan.spring.study.Car">
                <constructor-arg value="Ford"></constructor-arg>
                <constructor-arg value="Changan"></constructor-arg>
                <constructor-arg value="20000000" type="double"></constructor-arg>
            </bean>
        </property>
    </bean>
    
    <bean id="person2" class="logan.spring.study.Person">
        <constructor-arg value="Jerry"></constructor-arg>
        <constructor-arg value="25"></constructor-arg>
        <!-- 
        <constructor-arg ref="car"></constructor-arg>
        
        <constructor-arg><null/></constructor-arg>
        -->
        <constructor-arg ref="car"></constructor-arg>
        <property name="car.maxspeed" value="250"></property>
    </bean>
    <bean id="person3" class="logan.spring.study.collections.Person">
        <property name="name" value="Mike"></property>
        <property name="age" value="27"></property>
        <property name="cars">
            <list>
                <ref bean="car"/>
                <ref bean="car2"/>
            </list>
        </property>
    </bean>
    <bean id="newPerson" class="logan.spring.study.collections.NewPerson">
        <property name="name" value="Rose"></property>
        <property name="age" value="28"></property>
        <property name="car">
            <map>
                <entry key="AA" value-ref="car"></entry>
                <entry key="BB" value-ref="car2"></entry>
            </map>
        </property>
    </bean>
    <util:list id="cars">
        <ref bean="car"/>
        <ref bean="car2"/>
    </util:list>
    <bean id="dataSource" class="logan.spring.study.collections.DataSource">
        <property name="properties">
            <props>
                <prop key="user">root</prop>
                <prop key="password">1234</prop>
                <prop key="jdbcUrl">jdbc:mysql://test</prop>
                <prop key="driverClass">com.mysql.jdbc.Driver</prop>
            </props>
        </property>
    </bean>
    <bean id="person4" class="logan.spring.study.collections.Person">
        <property name="name" value="Jack"></property>
        <property name="age" value="30"></property>
        <property name="cars" ref="cars"></property>
    </bean>

</beans>

看输出结果

五月 19, 2017 10:25:03 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]3eb07fd3: startup date [Fri May 19 22:25:03 CST 2017]; root of context hierarchy
五月 19, 2017 10:25:03 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
HelloWorld‘s Constructor...
HelloWorld‘s Constructor...
NewPerson [name=Rose, age=28, car={AA=Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], BB=Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]}]
DataSource [properties={driverClass=com.mysql.jdbc.Driver, user=root, password=1234, jdbcUrl=jdbc:mysql://test}]
Person [name=Jack, age=30, cars=[Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]]]

下面看如何使用P命名空间

<?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:util="http://www.springframework.org/schema/util"
    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
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
    
    <!-- 配置bean
    class:bean的全类名,通过反射的方式在IOC容器中创建bean,所以要求Bean中必须有无参的构造函数
    id:表示容器的bean,id唯一 -->
    <bean id="hello" class="logan.spring.study.HelloWorld">
    </bean>
    
    <bean id="hello2" class="logan.spring.study.HelloWorld">
    </bean>
    
    <!-- 通过构造方法来配置Bean的属性 -->
    <bean id="car" class="logan.spring.study.Car">
        <constructor-arg value="Audi" index="0"></constructor-arg>
        <constructor-arg value="Shanghai" index="1"></constructor-arg>
        <constructor-arg value="3000000" index="2" type="double"></constructor-arg>
    </bean>
    <bean id="car2" class="logan.spring.study.Car">
        <constructor-arg value="Baoma" type="java.lang.String"></constructor-arg>
        <constructor-arg type="java.lang.String">
            <value><![CDATA[<Shanghai>]]></value>
        </constructor-arg>
        <constructor-arg type="int">
            <value>250</value>
        </constructor-arg>
    </bean>
    
    <bean id="person" class="logan.spring.study.Person">
        <property name="name" value="Tom"></property>
        <property name="age" value="24"></property>
        <property name="car">
            <bean class="logan.spring.study.Car">
                <constructor-arg value="Ford"></constructor-arg>
                <constructor-arg value="Changan"></constructor-arg>
                <constructor-arg value="20000000" type="double"></constructor-arg>
            </bean>
        </property>
    </bean>
    
    <bean id="person2" class="logan.spring.study.Person">
        <constructor-arg value="Jerry"></constructor-arg>
        <constructor-arg value="25"></constructor-arg>
        <!-- 
        <constructor-arg ref="car"></constructor-arg>
        
        <constructor-arg><null/></constructor-arg>
        -->
        <constructor-arg ref="car"></constructor-arg>
        <property name="car.maxspeed" value="250"></property>
    </bean>
    <bean id="person3" class="logan.spring.study.collections.Person">
        <property name="name" value="Mike"></property>
        <property name="age" value="27"></property>
        <property name="cars">
            <list>
                <ref bean="car"/>
                <ref bean="car2"/>
            </list>
        </property>
    </bean>
    <bean id="newPerson" class="logan.spring.study.collections.NewPerson">
        <property name="name" value="Rose"></property>
        <property name="age" value="28"></property>
        <property name="car">
            <map>
                <entry key="AA" value-ref="car"></entry>
                <entry key="BB" value-ref="car2"></entry>
            </map>
        </property>
    </bean>
    <util:list id="cars">
        <ref bean="car"/>
        <ref bean="car2"/>
    </util:list>
    <bean id="dataSource" class="logan.spring.study.collections.DataSource">
        <property name="properties">
            <props>
                <prop key="user">root</prop>
                <prop key="password">1234</prop>
                <prop key="jdbcUrl">jdbc:mysql://test</prop>
                <prop key="driverClass">com.mysql.jdbc.Driver</prop>
            </props>
        </property>
    </bean>
    <bean id="person4" class="logan.spring.study.collections.Person">
        <property name="name" value="Jack"></property>
        <property name="age" value="30"></property>
        <property name="cars" ref="cars"></property>
    </bean>
    
    <bean id="person5" class="logan.spring.study.collections.Person" p:age="31"
    p:name="Queen" p:cars-ref="cars">
    
    </bean>

</beans>
package logan.spring.study.collections;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Main {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        //1.创建Spring的IOC容器对象
        ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
        //Person person = (Person) ctx.getBean("person");
        NewPerson newPerson = (NewPerson) ctx.getBean("newPerson");
        System.out.println(newPerson);
        DataSource dataSource = ctx.getBean(DataSource.class);
        System.out.println(dataSource);
        Person person = (Person) ctx.getBean("person5");
        System.out.println(person);
        

    }

}

 

下面是输出结果

五月 19, 2017 10:32:33 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org[email protected]3eb07fd3: startup date [Fri May 19 22:32:33 CST 2017]; root of context hierarchy
五月 19, 2017 10:32:33 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [applicationContext.xml]
HelloWorld‘s Constructor...
HelloWorld‘s Constructor...
NewPerson [name=Rose, age=28, car={AA=Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], BB=Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]}]
DataSource [properties={driverClass=com.mysql.jdbc.Driver, user=root, password=1234, jdbcUrl=jdbc:mysql://test}]
Person [name=Queen, age=31, cars=[Car [brand=Audi, corp=Shanghai, price=3000000.0, maxspeed=250], Car [brand=Baoma, corp=<Shanghai>, price=0.0, maxspeed=250]]]

 

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