Metod Advice + inner object method invokes Question

[darkit]

Hi Alls,

I have 3 methods in my class

public void startRuleSet() {
    System.out.println("Start Rule Set");
    makeRule1();
    makeRule2();
  }

  public void makeRule1() {
    System.out.println("Rule 1");
  }

  public void makeRule2() {
    System.out.println("Rule 2");
  }

in spring config there're such lines:

  <bean id="myBefore" class="com.my.test.aop.MyBefore"/>

  <bean id="ruleSetAOPTest" class="com.my.test.aop.RuleSetAOPImpl"/>

  <bean id="ruleAdvisor"
    class="org.springframework.aop.support.RegexpMethodPointcutAdvisor">
    <property name="advice">
      <ref local="myBefore"/>
    </property>
    <property name="pattern">
      <value>.*Rule.*</value>
    </property>
  </bean>

  <bean id="ruleSetBean" class="org.springframework.aop.framework.ProxyFactoryBean">
    <property name="target">
      <ref local="ruleSetAOPTest"/>
    </property>
    <property name="proxyTargetClass">
      <value>true</value>
    </property>
    <property name="interceptorNames">
      <list>
        <value>ruleAdvisor</value>
      </list>
    </property>
  </bean>

And when i call startRuleSet

final RuleSetAOPImpl ruleSet = (RuleSetAOPImpl) context.getContext().getBean("ruleSetBean");
    ruleSet.startRuleSet();

I have advice invoke only on startRuleSet(), but i want that advice is invoked on makeRule* methods which are invoked inside startRuleSet method.

Is it possible ?

Thank's

[irbouho]

Please take a look at AOP, Proxies, and method calling in same instance and Pre-Interceptor in TransactionProxyFactory.
HTH

[darkit]

But in this case object has to know about AOP and that it is interceptored now.
I don't like such solution because i need clean pojo not agly hybrid.

Please take a look at AOP, Proxies, and method calling in same instance and Pre-Interceptor in TransactionProxyFactory.
HTH

[irbouho]

As I said in a previous post, this approach is intrusive. You may, however use AspectJ for less intrusive approach.

[darkit]

I cann't do it because my class instanses will load from db.
And i think it's impossible to use AspectJ in such case only runtime byte code manipulation.

As I said in a previous post, this approach is intrusive. You may, however use AspectJ for less intrusive approach.

[Laurent PETIT]

As I said in a previous post, this approach is intrusive. You may, however use AspectJ for less intrusive approach.

Hello,

What about this :

I think this problem could be "partially" solved with the use of CLIB instead of Dynamic Proxies : since the target class will be subclassed, calls to this() will first cause the overriden method to execute, thus allowing the AOP mechanism to work.

Of course there will still be some problems here with CGLib, since all the methods marked as "final" cannot be subclassed

Do I have the point ? Or did I miss something ?

[darkit]

You're right. I made this thing using cglib

As I said in a previous post, this approach is intrusive. You may, however use AspectJ for less intrusive approach.

Hello,

What about this :

I think this problem could be "partially" solved with the use of CLIB instead of Dynamic Proxies : since the target class will be subclassed, calls to this() will first cause the overriden method to execute, thus allowing the AOP mechanism to work.

Of course there will still be some problems here with CGLib, since all the methods marked as "final" cannot be subclassed

Do I have the point ? Or did I miss something ?

[oliverhutchison]

Do I have the point ? Or did I miss something?

You missed something.

Using CGLIB proxies will not solve this problem as, just like JDK proxies, they delegate to the target. See: http://forum.springframework.org/showthread.php?t=9926

Ollie

[darkit]

You're wrong
when i have 3 public methods:

public a() {
  b();
  c();
}

public b() {...}

public c() {...}

then using cglib proxy i can intercept for all 3 methods. And "a" method is invoked from outside but "b" and "c" from "a" and everything's working.

Do I have the point ? Or did I miss something?

You missed something.

Using CGLIB proxies will not solve this problem as, just like JDK proxies, they delegate to the target. See: http://forum.springframework.org/showthread.php?t=9926

Ollie

[/code]

[Andreas Senft]

I would say the difference between Java proxies and CGLIB proxies is the following:

A Java proxy effectively establishes a delegate. You call a method on the proxy which eventually delegates to the target. Once inside the target's method the invocation of another method will take place in the context of the target, not of the proxy.

I assume a CGLIB proxy establishes a subclass of the target class. So you never leave the context. Operating on "this" effectively operates on the subclass (proxy) instance. So subsequent invocations take place on the proxied methods (if not private).

It's a difference between delegation and inheritance, therefore the former does not work while the latter does.

Regards,
Andreas

P.S.: I'm no expert for CGLIB. It's just an explanation of how I think it works