·
先建立一個包:javamxj.spring.basic.MethodReplacer ,然后把以下5個文件放在這個包下。
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Hello.java
|
package
javamxj
.
spring
.
basic
.
MethodReplacer
;
public
interface Hello { ??? publicvoid sayHello(String s); }
|
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HelloImpl.java
|
package
javamxj
.
spring
.
basic
.
MethodReplacer
;
public
class HelloImpl implements Hello { ??? publicvoid sayHello(String name) { ??????? System.out.println("Hello: " + name); ??? } }
|
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HelloReplacer.java
|
package
javamxj
.
spring
.
basic
.
MethodReplacer
;
import
java
.
lang
.
reflect
.
Method
;
import
org
.
springframework
.
beans
.
factory
.
support
.
MethodReplacer
;
public
class HelloReplacer implements MethodReplacer { ??? publicObject reimplement(Object o, Method m, Object[] args) throwsThrowable {
??????? System.out.println("你好: " + args[0]); ??????? returnnull; ??? } }
|
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beans.xml
|
<?
xml
version
=
"
1.0
"
encoding
=
"
GBK
"
?>
<!
DOCTYPE
beans
PUBLIC
"-//SPRING//DTD BEAN//EN"
"http://www.springframework.org/dtd/spring-beans.dtd"
>
<
beans
>
??? <bean id="helloReplacer" class="javamxj.spring.basic.MethodReplacer.HelloReplacer"/> ??? ??? <bean id="helloA" class="javamxj.spring.basic.MethodReplacer.HelloImpl"/> ??? ??? <bean id="helloB" class="javamxj.spring.basic.MethodReplacer.HelloImpl"> ??????? <replaced-method name="sayHello" replacer="helloReplacer"/> ??? </bean> ??? </beans>
|
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Main.java
|
package
javamxj
.
spring
.
basic
.
MethodReplacer
;
import
org
.
springframework
.
beans
.
factory
.
BeanFactory
;
import
org
.
springframework
.
beans
.
factory
.
xml
.
XmlBeanFactory
;
import
org
.
springframework
.
core
.
io
.
ClassPathResource
;
import
org
.
springframework
.
core
.
io
.
Resource
;
public
class Main { ??? publicstaticvoid main(String[] args) { ??????? Resource res = new ClassPathResource( ??????????????? "javamxj/spring/basic/MethodReplacer/beans.xml"); ??????? BeanFactory ft = new XmlBeanFactory(res);
??????? // 沒有使用replaced-method ??????? Hello h = (Hello) ft.getBean("helloA"); ??????? h.sayHello("分享Java快樂"); ??????? ??????? // 使用replaced-method ??????? h=(Hello) ft.getBean("helloB"); ??????? h.sayHello("分享Java快樂");
??? } }
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?
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簡單說明一下:
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· Hello是一個接口類,實現面向接口編程。
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· HelloImpl類實現了Hello接口,簡單的輸出一個語句。
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· HelloReplacer類要實現MethodReplacer接口,reimplement中提供替換后的方法。
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· beans.xml中定義了三個bean,helloReplacer指向HelloReplacer類;helloA和helloB都指向HelloImpl類,其中helloB中定義了replaced-method。
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· 在Main類中,對比輸出使用replaced-method前后的語句。
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· 這次需要將 spring-framework主目錄\lib\cglib 目錄中的cglib-nodep-2.1_2.jar加入到項目的 Libraries中,使用其中的動態代理。
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運行結果:
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Hello: 分享Java快樂
你好: 分享Java快樂
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