在Spring problem AspectJ中使用Ajc编译器

Question

当我尝试用ajc编译器用spring编写aspectj时，我得到了下面的errror.when，我删除了aspectj，然后代码工作得很好，是不是有什么编译时的编织导致了问题

caused by: java.lang.ExceptionInInitializerError
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:100)
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:61)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:877)
... 31 more
Caused by: java.lang.NullPointerException
at com.cdf.dfdxc.aspect.logging.LoggingAspect.logEntry(LoggingAspect.java:76)
at com.cdfc.fdged.uow.UdfdFactory.<clinit>(UOWfdy.java:1)

Spring bean文件

<bean id="hibernateCertificateDao" class="com.Add.exasmple2.dao.HibernateCertificateDaoImpl" autowire="byType">
    <property name="hibernateTemplate">
        <ref bean="hibernateTemplate" />
    </property>
</bean>

<bean id="AddCert" class="com.Add.exasmple2.uow.AddCertUOW" lazy-init="true" autowire="byType">
    <constructor-arg ref="oXMapper"></constructor-arg>
</bean>

<bean id="uOWFactoryBean" class="com.Add.exasmple2.uow.UOWFactory" />

<bean id="businessProcessManager" class="com.Add.exasmple2.infrastructure.BusinessProcessManager"></bean>

<bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate" >
    <property name="sessionFactory">
        <ref bean="sessionFactory" />
    </property>
</bean>

                                        classpath:/resources/hibernate-mappings                                                                                         

<bean id="exampleDataSource" class="org.apache.commons.dbcp.BasicDataSource">
    <property name="driverClassName">
        <value>com.ibm.db2.jcc.DB2Driver</value>
    </property>
    <property name="url">
        <value>jdbc:db2://20.15.29.108:50001/XC128086</value>
    </property>
    <property name="password">
        <value>db2dut$</value>
    </property>
    <property name="username">
        <value>db2dut</value>
    </property>
</bean>

<bean id="exampleHibernateProperties"
    class="org.springframework.beans.factory.config.PropertiesFactoryBean">
    <property name="properties">
        <props>
            <prop key="hibernate.dialect">org.hibernate.dialect.DB2Dialect</prop>
            <prop key="hibernate.hbm2ddl.auto">update</prop>
            <prop key="hibernate.current_session_context_class">org.hibernate.context.ThreadLocalSessionContext
            </prop>
            <prop key="connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider
            </prop>
            <prop key="c3p0.acquire_increment">3</prop>
            <prop key="c3p0.max_size">30</prop>
            <prop key="c3p0.min_size">3</prop>
            <prop key="c3p0.max_statements">0</prop>
            <prop key="c3p0.idle_test_period">0</prop>
            <prop key="c3p0.timeout">0</prop>
            <prop key="current_session_context_class">thread</prop>
            <prop key="cache.provider_class">org.hibernate.cache.HashtableCacheProvider</prop>
            <prop key="connection.autocommit">true</prop>
            <prop key="show_sql">false</prop>
            <prop key="format_sql">false</prop>
            <prop key="use_sql_comments">false</prop>
            <prop key="hibernate.show_sql">false</prop>
        </props>
    </property>
</bean>



<tx:annotation-driven transaction-manager="transactionManager" />


<bean id="transactionManager"
    class="org.springframework.orm.hibernate3.HibernateTransactionManager">
    <property name="sessionFactory">
        <ref bean="sessionFactory" />
    </property>
</bean>

日志方面代码

  @Pointcut("within(com.csc.exceed.uow.*)")
public void loggingAspect() {

}

// invoked before the method execution
@Before("loggingAspect()")
public void logEntry(JoinPoint joinPoint) {

    Class<? extends Object> clazz = joinPoint.getTarget().getClass();
    String name = joinPoint.getSignature().getName();

    if (ArrayUtils.isEmpty(joinPoint.getArgs())) {
        if (!(name.startsWith("get")) || (name.startsWith("set")))
            logger.log(LogLevel.INFO, clazz, null, BEFORE_STRING, name,
                    constructArgumentsString(clazz, joinPoint.getArgs()));
    } else {

        logger.log(LogLevel.INFO, clazz, null, BEFORE_WITH_PARAMS_STRING,
                name, constructArgumentsString(clazz, joinPoint.getArgs()));

    }
}

Answer 1

在不知道哪一行是76行的情况下是很困难的：

at com.cdf.dfdxc.aspect.logging.LoggingAspect.logEntry(LoggingAspect.java:76)

但是您使用的是一个非常激进的切入点

@Pointcut("within(com.csc.exceed.uow.*)")
public void loggingAspect() {}

这将匹配所有类型的事件，不仅是方法执行，还包括静态和实例初始化器、字段访问等(请参阅AspectJ Quick Reference中的原语切入点概述)。

如果出现以下任一情况：

• 为joinPoint.getTarget()返回null，则此行将抛出NPE：

Class<？扩展clazz = joinPoint.getTarget().getClass();

• returns null Object> joinPoint.getSignature()，此行将抛出NPE：

String name = joinPoint.getSignature().getName();

• Also，在这里，您将检查是否有null或空参数：

if (ArrayUtils.isEmpty(joinPoint.getArgs(){ if (!(name.startsWith("get")) || (name.startsWith(“set”) logger.log(LogLevel.INFO，clazz，null，BEFORE_STRING，name，

但是您仍然在使用args：

clazz(clazz，joinPoint.getArgs()；

这也可能引发NPE，具体取决于constructArgumentsString()中的代码。

检查第76行发生了哪种情况，您就有了失败的候选者。但我的第一个提示是用execution或call切入点替换您积极的通用切入点。

我将使用一个组合的切入点，以模块化的方式定义：

// you can easily reuse this
@Pointcut("within(com.csc.exceed.uow.*)")
public void myApp() {}

// and this
@Pointcut("execution(* *.*(..))")
public void methodExecution(){}

// but this is the pointcut you are actually matching
@Pointcut("myApp() && methodExecution()")
public void methodExecutionInMyApp(){}

@Before("methodExecutionInMyApp()")
public void logMethodExecutions(JoinPoint jp){
    // your code here
}

下面是如何让类变得NPE安全的方法：

Class<?> clazz = joinPoint.getTarget() !=null 
               ? joinPoint.getTarget().getClass() 
               : null;