由spring的工厂构造bean想到的

 1 <bean id="tracing" class="brave.spring.beans.TracingFactoryBean">
 2 ...
 3 <property name="propagationFactory">
 4     <bean id="propagationFactory" class="brave.propagation.ExtraFieldPropagation"
 5         factory-method="newFactory">
 6         <constructor-arg index="0">
 7             <util:constant static-field="brave.propagation.B3Propagation.FACTORY" />
 8         </constructor-arg>
 9         <constructor-arg index="1">
10             <list>
11                 <value>user-name</value>
12             </list>
13         </constructor-arg>
14     </bean>
15 </property>
16 </bean>

1 <bean id="carFactory" class="com.home.factoryMethod.CarInstanceFactory">
2 ...
3 </bean>
4 <bean id="car4" factory-bean="carFactory" factory-method="getCar">
5     <constructor-arg value="4"></constructor-arg>           
6 </bean>

1 ApplicationContext ctx = new ClassPathXmlApplicationContext("bean-factoryMethod.xml");
2 Car car1 = (Car) ctx.getBean("car4");

1 <constructor-arg index="0">
2     <util:constant static-field="brave.propagation.B3Propagation.FACTORY" />
3 </constructor-arg>

 1 <bean id="some1" class="cn.itcast.spring._util.Some">
 2     <property name="val" value="some instance1" />
 3 </bean>
 4 <bean id="some2" class="cn.itcast.spring._util.Some">
 5     <property name="val" value="some instance2" />
 6 </bean>
 7 <bean id="some3" class="cn.itcast.spring._util.Some">
 8     <property name="val" value="some instance3" />
 9 </bean>
10 <util:list id="strArray">
11     <value>Hello</value>
12     <value>Welcome</value>
13 </util:list>
14 <util:list id="objArray">
15     <ref bean="some1" />
16     <ref bean="some2" />
17     <ref bean="some3" />
18 </util:list>
19 <util:list id="list" list-class="java.util.ArrayList">
20     <ref bean="some1"/>
21     <ref bean="some2" />
22     <ref bean="some3" />
23 </util:list>
24 <util:map id="map" map-class="java.util.HashMap" >
25     <entry key="key1" value-ref="some1"/>
26     <entry key="key2" value-ref="some2"/>
27     <entry key="key3" value-ref="some3"/>
28 </util:map>
29 <bean id="someBean" class="cn.itcast.spring._util.SomeBean">
30     <property name="someStrArray" ref="strArray"/>
31     <property name="someObjArray" ref="objArray"/>
32     <property name="someList" ref="list"/>
33     <property name="someMap" ref="map"/>
34 </bean>