spring-day01

在applicationContext.xml中配置如下代码

<!-- 
    在spring主配置文件中,告诉spring IOC容器,user在这里,
    spring一旦运行起来就会首先加载该配置文件作为spring的上下文
    创建user对象(实例)    
     -->
    <bean id="user" class="com.spring.di.User">
        <property name="id" value="2"></property>
        <property name="username">
            <value>marry</value>
        </property>
    </bean>
    
    <bean id="person" class="com.spring.di.Person">
        <property name="name">
            <value>zhangsan</value>
        </property>
        <property name="age" value="32"></property>
        <property name="sal" value="3200"></property>
        <property name="user">
            <ref bean="user"></ref>
        </property>
        <property name="user2">
            <!-- 内部bean 作用范围只在当前person bean 的内部
                   外部是看不见 不能被外部bean使用
             -->
            <bean class="com.spring.di.User">
                <property name="id" value="22"></property>
                <property name="username">
                    <value>marry2</value>
                </property>
            </bean>
        </property>
    </bean>
    <bean id="dog" class="com.spring.di.Dog">
        <!-- 根据构造器参数的索引来注入 -->
        <!-- <constructor-arg value="小花花" index="0"></constructor-arg>
        <constructor-arg value="白色" index="1"></constructor-arg> -->
        
        <!-- 根据构造器参数类型注入 -->
        <constructor-arg value="小花花" index="0" type="java.lang.String"></constructor-arg>
        <constructor-arg value="白色" index="1" type="java.lang.String"></constructor-arg>
        <constructor-arg value="1" index="2" type="java.lang.Integer"></constructor-arg>
        <constructor-arg type="com.spring.di.User" ref="user"></constructor-arg>
    </bean>
    
    <bean id="cat" class="com.spring.di.Cat">
        <property name="name" value="詹尼"></property>
        <!-- 注入null值    也可以不注入 -->
        <property name="color">
            <null />
        </property>
    </bean>
    
    <!-- 集合类型注入 -->
    <bean id="pet" class="com.spring.di.Pet">
        <!-- List类型注入 -->
        <property name="dogs">
            <list>
                <value>小花花</value>
                <value>珍妮</value>
                <value>旺财</value>
                <value>小强</value>
            </list>
        </property>
        
        <!-- Set类型注入 -->
        
        <property name="cats">
            <set>
                <value>小花花</value>
                <value>珍妮</value>
                <value>旺财</value>
                <value>小强</value>
            </set>
        </property>
        
        <!-- Map类型注入 -->
        <property name="pigs">
            <map>
                <entry>
                    <key>
                        <value>1</value>
                    </key>
                    <value>大白</value>
                </entry>
                <entry key="2" value="小白"></entry>
            </map>
        </property>
        
        <!-- 数组类型注入 -->
        <property name="birds">
            <list>
                <value>新天问</value>
                <value>喜鹊</value>
            </list>
        </property>
        
        <!-- Properties类型属性注入 -->
        <property name="pp">
            <props>
                <prop key="p1">p1_value</prop>
                <prop key="p2">p2_value</prop>
            </props>
        </property>
        
    </bean>
    
    <!-- 自动装配
        byName byTime
         -->
    <bean id="a" class="com.spring.auto.A">
        <property name="aname" value="AAA"></property>
    </bean>
    <bean id="b" class="com.spring.auto.B">
        <property name="bname" value="BBB"></property>
    </bean>
    
    <!-- 这是正常的对象属性注入 -->
    <bean id="ab" class="com.spring.auto.AB">
        <property name="a">
            <ref bean="a"></ref>
        </property>
        <property name="b">
            <ref bean="b"></ref>
        </property>
    </bean>
    
    <!-- byName 
        spring的IOC容器会根据AB类的属性名称会去在容器中自动查找id等于其属性名称的bean进行自动装配(实现注入)
    -->
    <bean id="ab_byName" class="com.spring.auto.AB" autowire="byName">
    </bean>
    
    <!-- byType
        spring的IOC容器会根据AB类的属性类型去容器中自动查找类型等同于其属性类型的bean进行自动装配(实现注入)
        如果出现了多个类型相同的bean 使用byType自动装配就会出现异常
         org.springframework.beans.factory.NoUniqueBeanDefinitionException
    -->
    <!-- <bean id="b1" class="com.spring.auto.B">
        <property name="bname" value="BBB1"></property>
    </bean> -->
    
    <bean id="ab_byType" class="com.spring.auto.AB" autowire="byType">
    </bean>
    
    <!-- 分散装配
        org.springframework.beans.factory.config.PropertyPlaceholderConfigurer
     -->
     <bean id="propertyPlaceholderConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
         <property name="location">
             <value>test.properties</value>
         </property>
     </bean>

　test.propertie文件

　　　　key1=value1
　　　　key2=value2
　　　　key3=value3

    <bean id="testProperties" class="com.spring.auto.TestProperties">
        <property name="key1" value="${key1}"></property>
        <property name="key2" value="${key2}"></property>
        <property name="key3" value="${key3}"></property>
    </bean>

测试代码如下

ApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
        /*AB ab= (AB) ac.getBean("ab");
        System.out.println(ab);*/
        
        AB ab_byName= (AB) ac.getBean("ab_byName");
        System.out.println(ab_byName);
        
    /*    AB ab_byType= (AB) ac.getBean("ab_byType");
        System.out.println(ab_byType);*/
        
        /*TestProperties testProperties= (TestProperties) ac.getBean("testProperties");
        System.out.println(testProperties);*/

/*        User user = new User();    //代码的耦合在一起,不利于后期代码的维护
        user.setUsername("jack");
        
        System.out.println(user.toString());
        System.out.println("------------------------");
        
        User user2 = new User(1,"tom","123");
        System.out.println(user2.toString());*/
        
        //启动spring的IOC容器  加载主配置文件
/*         @SuppressWarnings("resource")
        ApplicationContext ac= new ClassPathXmlApplicationContext("applicationContext.xml");
         
         User user =(User) ac.getBean("user"); 
         System.out.println(user.toString());*/
        ApplicationContext ac=new ClassPathXmlApplicationContext("applicationContext.xml");
        Person person = (Person) ac.getBean("person");
        System.out.println(person.toString());
        
        /*Cat cat=(Cat) ac.getBean("cat");
        System.out.println(cat);*/
        
        /*Pet pet= (Pet) ac.getBean("pet");
        System.out.println(pet);*/