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1 从http://www.springframework.org下载spring
2 用eclipse新建java项目
3 建立我们的业务方法接口
public interface businessobject {
public void dosomething();
public void doanotherthing();
}
import org.apache.commons.logging.log;
import org.apache.commons.logging.logfactory;public interface businessobject {
public void dosomething();
public void doanotherthing();
}
import org.apache.commons.logging.log;
import org.apache.commons.logging.logfactory;
4 实现业务方法，注意这是的setwords使用了依赖注入，所谓依赖注入就是把配置文件中的字符串什么的在程序运行时“自动”放到我们的程序中来。如果不是这样，我们就只能在代码中固化这些东西，从而违背了面向对象的依赖倒置原则，还有一种满足依赖倒置的方法，即依赖查询，这就是所谓的factory模式，即在代码中请求某种抽象的东西，然后根据配置得到它，但这种办法向对于依赖注入多了对环境的依赖，且代码冗余，ejb的jndi查询就属于这种。另外我们的spring配置文件是以bean为核心的，就是我们写的一个类，在xml中描述它的名称、位置和涵盖的内容、关系。
public class businessobjectimpl implements businessobject {
private string words;
public void setwords(string words){
this.words = words;
}
public void dosomething() {
log log = logfactory.getlog(this.getclass());
log.info(words);
}
public void doanotherthing() {
log log = logfactory.getlog(this.getclass());
log.info("another thing");
}
}public class businessobjectimpl implements businessobject {
private string words;
public void setwords(string words){
this.words = words;
}
public void dosomething() {
log log = logfactory.getlog(this.getclass());
log.info(words);
}
public void doanotherthing() {
log log = logfactory.getlog(this.getclass());
log.info("another thing");
}
}
5 建立一个运行方法类，从配置文件spring-beans.xml中读入bo这个类的定义，然后实例化一个对象
import org.springframework.beans.factory.xml.xmlbeanfactory;
import org.springframework.core.io.classpathresource;
public class main {
public static void main(string[] args){
xmlbeanfactory xbf = new xmlbeanfactory(new classpathresource("spring-beans.xml"));
businessobject bo = (businessobject)xbf.getbean("bo");
bo.dosomething();
bo.doanotherthing();
}
}import org.springframework.beans.factory.xml.xmlbeanfactory;
import org.springframework.core.io.classpathresource;
public class main {
public static void main(string[] args){
xmlbeanfactory xbf = new xmlbeanfactory(new classpathresource("spring-beans.xml"));
businessobject bo = (businessobject)xbf.getbean("bo");
bo.dosomething();
bo.doanotherthing();
}
}
6 建立一个拦截器类invoke是methodinterceptor必须实现的方法，表示拦截时的动作，大家仔细体会代码中的含义
import org.aopalliance.intercept.methodinterceptor;
import org.aopalliance.intercept.methodinvocation;
import org.apache.commons.logging.log;
import org.apache.commons.logging.logfactory;
public class myinterceptor implements methodinterceptor {
private string before, after;
public void setafter(string after) {
this.after = after;
}
public void setbefore(string before) {
this.before = before;
}
public object invoke(methodinvocation invocation) throws throwable {
log log = logfactory.getlog(this.getclass());
log.info(before);
object rval = invocation.proceed();
log.info(after);
return rval;
}
}import org.aopalliance.intercept.methodinterceptor;
import org.aopalliance.intercept.methodinvocation;
import org.apache.commons.logging.log;
import org.apache.commons.logging.logfactory;
public class myinterceptor implements methodinterceptor {
private string before, after;
public void setafter(string after) {
this.after = after;
}
public void setbefore(string before) {
this.before = before;
}
public object invoke(methodinvocation invocation) throws throwable {
log log = logfactory.getlog(this.getclass());
log.info(before);
object rval = invocation.proceed();
log.info(after);
return rval;
}
}
7 建立配置文件组织上面的类之间的关系，aop有切入点和增强这两个重要的概念，把两个概念结合到一起，就是一个在某个方法执行的时候附加执行，切入点表示在哪里附加，增强表示附加什么，配置文件中的mypointcut表示切入点，myinterceptor表示增强的内容，myadvisor表示增强器，即两者的结合，在bo这个bean中，我们把这个增强器附加到了bo这个bean上。
<?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="businessobjectimpl" class="businessobjectimpl">
<property name="words">
<value>正在执行业务方法</value>
</property>
</bean>
<bean id="myinterceptor" class="myinterceptor">
<property name="before">
<value>执行业务方法前</value>
</property>
<property name="after">
<value>执行业务方法后</value>
</property>
</bean>
<bean id="mypointcut" class="org.springframework.aop.support.jdkregexpmethodpointcut">
<property name="patterns">
<list>
<value>businessobject.dosomething</value>
</list>
</property>
</bean>
<bean id="myadvisor" class="org.springframework.aop.support.defaultpointcutadvisor">
<property name="pointcut" ref="mypointcut"/>
<property name="advice" ref="myinterceptor"/>
</bean>
<bean id="bo" class="org.springframework.aop.framework.proxyfactorybean">
<property name="target">
<ref local="businessobjectimpl"/>
</property>
<property name="proxyinterfaces">
<value>businessobject</value>
</property>
<property name="interceptornames">
<list>
<value>myinterceptor</value>
<value>myadvisor</value>
</list>
</property>
</bean>
</beans><?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="businessobjectimpl" class="businessobjectimpl">
<property name="words">
<value>正在执行业务方法</value>
</property>
</bean>
<bean id="myinterceptor" class="myinterceptor">
<property name="before">
<value>执行业务方法前</value>
</property>
<property name="after">
<value>执行业务方法后</value>
</property>
</bean>
<bean id="mypointcut" class="org.springframework.aop.support.jdkregexpmethodpointcut">
<property name="patterns">
<list>
<value>businessobject.dosomething</value>
</list>
</property>
</bean>
<bean id="myadvisor" class="org.springframework.aop.support.defaultpointcutadvisor">
<property name="pointcut" ref="mypointcut"/>
<property name="advice" ref="myinterceptor"/>
</bean>
<bean id="bo" class="org.springframework.aop.framework.proxyfactorybean">
<property name="target">
<ref local="businessobjectimpl"/>
</property>
<property name="proxyinterfaces">
<value>businessobject</value>
</property>
<property name="interceptornames">
<list>
<value>myinterceptor</value>
<value>myadvisor</value>
</list>
</property>
</bean>
</beans>
8 运行main类，观察控制台输出结果，重新审查代码，反思为什么会出现这种结果。
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