当动态代理遇到ioc （四）真正的cglib

0 当动态代理遇到ioc （二）cglib 中的代理仍然不能切子函数，所以有本篇

1 此前已经解决cglib与asm冲突：当动态代理遇到ioc （三）cglib与asm jar包冲突

2 事务的try catch模型由exception扩叨叨throwable

3 抽象层

由于我们反射调用方法时，不再是method.invoke(origin object, args[])，所以抽象层要修改一下

protected Object invokeHasTransactional(SCEF_DB_TRANSACTIONAL scef_db_transactional, Method method, Object[] args, MethodProxy methodProxy, Object oCglib) throws Throwable {

protected Object invokeNoTransactional(Method method, Object[] args, MethodProxy methodProxy, Object oCglib) throws Throwable {

　　

Object returnValue = aopInvoke(method, args, methodProxy, oCglib);

　　

jdk

    protected Object aopInvoke(Method method, Object [] args, MethodProxy methodProxy, Object oCglib) throws Throwable {
        Object returnValue = method.invoke(target, args);
        return returnValue;
    }

　　

        if(scef_db_transactional != null) {
            res = invokeHasTransactional(scef_db_transactional, method, args, null, null);
        } else {
            res = invokeNoTransactional(method, args, null, null);
        }

　　

cglib

    @Override
    protected Object aopInvoke(Method method, Object[] args, MethodProxy methodProxy, Object oCglib) throws Throwable {
////////return method.invoke(target, args);
        return methodProxy.invokeSuper(oCglib, args);
    }

　　

        if (scef_db_transactional != null) {
            res = invokeHasTransactional(scef_db_transactional, null, objects, methodProxy, o);
        } else {
            res = invokeNoTransactional(null, objects, methodProxy, o);
        }

　　

4 ioc反哺

解决了3形成了子函数切面后，报错：

首次处理 class sun.myproxybean.MyServiceImpl的ioc
处理 class sun.myproxybean.MyServiceImpl的myMapper1
处理 class sun.myproxybean.MyServiceImpl的myMapper2
处理 class sun.myproxybean.MyServiceImpl的myDao
public void sun.myproxybean.MyServiceImpl.multi()
@sun.myproxy.MY_TRANSACTIONAL()
public final void sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.multi()
null
public abstract void sun.myproxybean.MyService.multi()
null
Exception in thread "main" java.lang.RuntimeException: java.lang.NullPointerException
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:112)
	at sun.myproxy.OdsTransactionCglibFactory.intercept(OdsTransactionCglibFactory.java:65)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.multi(<generated>)
	at sun.mybatis.Main.main(Main.java:58)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: java.lang.NullPointerException
	at sun.myproxybean.MyServiceImpl.multi(MyServiceImpl.java:29)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.CGLIB$multi$0(<generated>)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d$$FastClassByCGLIB$$8fca1f76.invoke(<generated>)
	at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
	at sun.myproxy.OdsTransactionCglibFactory.aopInvoke(OdsTransactionCglibFactory.java:73)
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:100)
	... 8 more

显示ioc null了，故我们回顾一下IOC()中，反哺是反到原始对象

为了切子函数，不再使用method.invoke(origin object, args[])原对象，而是使用代理对象（子类对象）methodProxy.invokeSuper(oCglib, args);，因此反哺应在子类对象上进行

protected Object getTarget() {
    return this.target;
}

@SuppressWarnings("squid:S3011")
protected void IOC() throws IllegalAccessException {
    if (!alreadyIOC) {
        Class clProxy = target.getClass();
        Field[] fields = clProxy.getDeclaredFields();
        for (Field field : fields) {

            field.setAccessible(true);
            if (!field.isAnnotationPresent(getBeanInjectAnnotationGuice()))
                continue;
            String name = field.getName();
            Class fieldType = field.getType();
            Object obj = getBeanFromFactoryGuice(fieldType);
            if (obj != null)
                field.set(getTarget(), obj);
        }
        alreadyIOC = true;
    }
}

public class OdsTransactionCglibFactory extends OdsTransactionProxyFactory implements MethodInterceptor {

    public OdsTransactionCglibFactory(Object target) {
        super(target);
    }

    private Object targetCglib;

    @Override
    protected Object getTarget() {
        return targetCglib;
    }

@Override
public Object getProxyInstance() {
    Enhancer en = new Enhancer();
    en.setSuperclass(target.getClass());
    en.setCallback(this);
    Object oCglib = en.create();
    this.targetCglib = oCglib;
    return oCglib;
}

5 发现一个bug

    @Inject
    private MyDao myDao;   // https://www.cnblogs.com/silyvin/p/14237270.html 第5点
//    private MyDaoImpl myDao;  // 导致myDao不是注入代理类对象，而是new MyDaoImpl，guice会自己newInstance一个

6 对于接口MyService中没有，仅在MyServiceImpl中有的子函数，处理“迎合某些人习惯将注解加到接口上”的时候去取接口的getMethod时报错

首次处理 class sun.myproxybean.MyServiceImpl的ioc
处理 class sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d的myMapper1
处理 class sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d的myMapper2
处理 class sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d的myDao
public void sun.myproxybean.MyServiceImpl.multi()
@sun.myproxy.MY_TRANSACTIONAL()
public final void sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.multi()
null
public abstract void sun.myproxybean.MyService.multi()
null
Exception in thread "main" java.lang.RuntimeException: java.lang.NoSuchMethodException: sun.myproxybean.MyService.subFunction()
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:117)
	at sun.myproxy.OdsTransactionCglibFactory.intercept(OdsTransactionCglibFactory.java:74)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.multi(<generated>)
	at sun.mybatis.Main.main(Main.java:58)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: java.lang.NoSuchMethodException: sun.myproxybean.MyService.subFunction()
	at java.lang.Class.getMethod(Class.java:1786)
	at sun.myproxy.OdsTransactionCglibFactory.intercept(OdsTransactionCglibFactory.java:42)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.subFunction(<generated>)
	at sun.myproxybean.MyServiceImpl.multi(MyServiceImpl.java:30)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.CGLIB$multi$0(<generated>)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d$$FastClassByCGLIB$$8fca1f76.invoke(<generated>)
	at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
	at sun.myproxy.OdsTransactionCglibFactory.aopInvoke(OdsTransactionCglibFactory.java:83)
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:105)
	... 8 more

jdk动态代理的子函数没有办法切，被切到的一定是接口中有的方法，所以天然无此问题；而cglib会切到大概率没有事务注解的子函数，所以就暴露了这个问题

@Override
public Object intercept(Object o, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {

    IOC();

    // ewirweod
    MY_TRANSACTIONAL scef_db_transactional = method.getAnnotation(MY_TRANSACTIONAL.class);

    // 迎合有些人习惯将注解加到接口上
    Class[] interfaces = target.getClass().getInterfaces();
    if(scef_db_transactional == null) {
        for(Class inter : interfaces) {
            try {
                Method classMethod = inter.getMethod(method.getName(), method.getParameterTypes());
                scef_db_transactional = classMethod.getAnnotation(MY_TRANSACTIONAL.class);
            } catch (NoSuchMethodException e1) {
                ; 
            } catch (Throwable e) {
                e.printStackTrace();
            }
            break;
        }
    }

6.5 又引出了一个知识：

        // MyServiceImpl&&CGLIB.method  uewoqruwiiii
        {
            Method classMethod = o.getClass().getMethod(method.getName(), method.getParameterTypes());
            System.out.println(classMethod);
            MY_TRANSACTIONAL my_transactional = classMethod.getAnnotation(MY_TRANSACTIONAL.class);
            System.out.println(my_transactional);
        }

这个地方居然也报错了

public class MyServiceImpl implements MyService {

    。。。。。

    /**
     * public o.getClass().getMethod 可以找到
     * protected 不行
     */
    public void subFunction() {
        System.out.println(this);
    }

 原因为：

getDeclaredMethod*()获取的是类自身声明的所有方法，包含public、protected和private方法。getMethod*()获取的是类的所有共有方法，这就包括自身的所有public方法，和从基类继承的、从接口实现的所有public方法。

anyway，所有getMethod方法都加上try catch throwable吧，以免影响主体进程

7 最终的日志

首次处理 class sun.myproxybean.MyServiceImpl的ioc
处理 class sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d的myMapper1
处理 class sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d的myMapper2
处理 class sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d的myDao
public void sun.myproxybean.MyServiceImpl.multi()
@sun.myproxy.MY_TRANSACTIONAL()
public final void sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.multi()
null
public abstract void sun.myproxybean.MyService.multi()
null
protected void sun.myproxybean.MyServiceImpl.subFunction()
null
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
首次处理 class sun.myproxybean.MyDaoImpl的ioc
处理 class sun.myproxybean.MyDaoImpl$$EnhancerByCGLIB$$4b5f7f6c的myMapper2
public void sun.myproxybean.MyDaoImpl.multi()
@sun.myproxy.MY_TRANSACTIONAL()
public final void sun.myproxybean.MyDaoImpl$$EnhancerByCGLIB$$4b5f7f6c.multi()
null
public abstract void sun.myproxybean.MyDao.multi()
null
Exception in thread "main" java.lang.RuntimeException: java.lang.RuntimeException: java.lang.ArithmeticException: / by zero
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:117)
	at sun.myproxy.OdsTransactionCglibFactory.intercept(OdsTransactionCglibFactory.java:74)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.multi(<generated>)
	at sun.mybatis.Main.main(Main.java:58)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: java.lang.RuntimeException: java.lang.ArithmeticException: / by zero
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:117)
	at sun.myproxy.OdsTransactionCglibFactory.intercept(OdsTransactionCglibFactory.java:74)
	at sun.myproxybean.MyDaoImpl$$EnhancerByCGLIB$$4b5f7f6c.multi(<generated>)
	at sun.myproxybean.MyServiceImpl.multi(MyServiceImpl.java:33)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d.CGLIB$multi$1(<generated>)
	at sun.myproxybean.MyServiceImpl$$EnhancerByCGLIB$$5b3ba48d$$FastClassByCGLIB$$8fca1f76.invoke(<generated>)
	at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
	at sun.myproxy.OdsTransactionCglibFactory.aopInvoke(OdsTransactionCglibFactory.java:83)
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:105)
	... 8 more
Caused by: java.lang.ArithmeticException: / by zero
	at sun.myproxybean.MyDaoImpl.multi(MyDaoImpl.java:18)
	at sun.myproxybean.MyDaoImpl$$EnhancerByCGLIB$$4b5f7f6c.CGLIB$multi$0(<generated>)
	at sun.myproxybean.MyDaoImpl$$EnhancerByCGLIB$$4b5f7f6c$$FastClassByCGLIB$$e94f8239.invoke(<generated>)
	at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
	at sun.myproxy.OdsTransactionCglibFactory.aopInvoke(OdsTransactionCglibFactory.java:83)
	at sun.myproxy.OdsTransactionProxyFactory.invokeHasTransactional(OdsTransactionProxyFactory.java:105)
	... 16 more