spring 用來使程序解耦，較重要的有aop（切面編程）和ioc(反向注入)
ioc用來使數據、對象和業務程序 解耦,即在什麼地方需要一個對象，你自己不用去通過new 生成你需要的對象，而是通過spring的bean工廠爲注入這樣一個對象
aop用來使業務邏輯和通常可複用的其他交叉邏輯（安全，事物，日誌） 解耦，即將交叉邏輯（比如安全，日誌，事務等），封裝成一個切面，然後注入到目標對象。
for example:
hello_ioc.java:
package org.dao.impl;
public class hello_ioc {
private String hello_ioc = null;
public String getHello_ioc() {
return hello_ioc;
}
public void setHello_ioc(String hello_ioc) {
this.hello_ioc = hello_ioc;
}
}
Hello.java:
package org.dao.impl;
public class Hello implements IHello {
@Override
public void hello(String hello) {
// TODO Auto-generated method stub
System.out.println("Hello:" + hello);
}
}
IHello.java:
package org.dao.impl;
public interface IHello {
public void hello(String hello);
/*public void sethello(String haha);
public String gethello();*/
}
LogBeforeMethod.java:
package org.log;
import java.lang.reflect.Method;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.springframework.aop.MethodBeforeAdvice;
public class LogBeforeMethod implements MethodBeforeAdvice {
private Logger logger = Logger.getLogger(this.getClass().getName());
@Override
public void before(Method method, Object[] arg1, Object arg2)
throws Throwable {
// TODO Auto-generated method stub
logger.log(Level.INFO, "method start..." + method);
System.out.println("LogBeforeAdvice: method start... " + method);
}
}
TestBefore.java:
package org.spring.test;
import org.dao.impl.IHello;
import org.dao.impl.hello_ioc;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class TestBefore {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");
//獲取的是Hello的代理對象
//for aop
IHello helloProxy = (IHello) ctx.getBean("hello");
helloProxy.hello("kkf");
//for ioc
hello_ioc helloioc = (hello_ioc)ctx.getBean("hello_ioc");
System.out.println(helloioc.getHello_ioc());
}
}
applicationContext.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">
<beans>
<bean id = "Hello1" class="org.dao.impl.Hello"></bean>
<bean id="logBefore" class="org.log.LogBeforeMethod"></bean>
<!-- aop -->
<bean id="hello" class="org.springframework.aop.framework.ProxyFactoryBean">
<property name="proxyInterfaces" value="org.dao.impl.IHello"></property>
<!-- 代理對象 -->
<property name="target" ref="Hello1"></property>
<!-- <property name ="hehe"><value>kkongyang</value></property> -->
<!-- 攔截器 -->
<property name="interceptorNames">
<list>
<value>logBefore</value>
</list>
</property>
</bean>
<!-- ioc -->
<bean id="hello_ioc" class="org.dao.impl.hello_ioc">
<property name ="hello_ioc"><value>kkfkkf</value></property>
</bean>
</beans>