此内容没有您所选择的语言版本。

5.3. Applying An Aspect

Now that you have a valid distribution containing everything you need, you can configure jboss-beans.xml to apply the audit aspect. It is in examples/User_Guide/gettingStarted/commandLineClient/target/client-aop.dir.

<?xml version="1.0" encoding="UTF-8"?>

<deployment xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="urn:jboss:bean-deployer:2.0 bean-deployer_2_0.xsd"
            xmlns="urn:jboss:bean-deployer:2.0">

  <bean name="AspectManager" class="org.jboss.aop.AspectManager">
    <constructor factoryClass="org.jboss.aop.AspectManager"
		 factoryMethod="instance"/>
  </bean>

  <aop:aspect xmlns:aop="urn:jboss:aop-beans:1.0"
	      name="AuditAspect" class="org.jboss.example.aspect.AuditAspect"
	      method="audit" pointcut="execution(public org.jboss.example.service.HRManager->new(..)) OR                                        execution(public * org.jboss.example.service.HRManager->*(..))">
  </aop:aspect>

  ...

</deployment>

<?xml version="1.0" encoding="UTF-8"?>

<deployment xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
            xsi:schemaLocation="urn:jboss:bean-deployer:2.0 bean-deployer_2_0.xsd"
            xmlns="urn:jboss:bean-deployer:2.0">

  <bean name="AspectManager" class="org.jboss.aop.AspectManager">
    <constructor factoryClass="org.jboss.aop.AspectManager"
		 factoryMethod="instance"/>
  </bean>

  <aop:aspect xmlns:aop="urn:jboss:aop-beans:1.0"
	      name="AuditAspect" class="org.jboss.example.aspect.AuditAspect"
	      method="audit" pointcut="execution(public org.jboss.example.service.HRManager->new(..)) OR                                        execution(public * org.jboss.example.service.HRManager->*(..))">
  </aop:aspect>

  ...

</deployment>

Copy to Clipboard

Toggle word wrap

Procedure 5.2. Explanation of the Code to Apply an Aspect

Before you can apply your aspect to any classes, you need to create an instance of org.jboss.aop.AspectManager using a <bean> element. A factory method is used here instead of calling a conventional constructor, since only one instance of the AspectManager in the JVM is necessary at run-time.
Next an instance of our aspect called AuditAspect is created, using the <aop:aspect> element. This looks similar to the <bean> element because it has name and class attributes that are used in the same way. However it also has method and pointcut attributes that you can use to apply or bind an advice within the aspect to constructors and methods within other classes. These attributes bind the audit advice to all public constructors and methods within the HRManager class. Only the audit method needs to be specified, since it has been overloaded within the AuditAspect class with different parameters. JBoss AOP knows at run-time which to select, depending on whether a constructor or method invocation is being made.

This additional configuration is all that is needed to apply the audit aspect at run-time, adding auditing behavior to the Human Resources service. You can test this by running the client using the run.sh script. A log directory is created on start-up alongside the lib directory when the AuditAspect bean is created by the Microcontainer. Each deployment of the Human Resources service causes a new log file to appear within the log directory. The log file contains a record of any calls made from the client to the service. It is named something similar to auditLog-28112007-163902, and contains output similar to Example 5.4, “Example AOP Log Output”.

Example 5.4. Example AOP Log Output

        Method: getEmployees Return: []
        Method: addEmployee Args: (Santa Claus, 1 Reindeer Avenue, Lapland City - 25/12/1860) Return: true
        Method: getSalary Args: (Santa Claus, null - Birth date unknown) Return: 10000
        Method: getEmployees Return: [(Santa Claus, 1 Reindeer Avenue, Lapland City - 25/12/1860)]
        Method: isHiringFreeze Return: false
        Method: getEmployees Return: [(Santa Claus, 1 Reindeer Avenue, Lapland City - 25/12/1860)]
        Method: getSalaryStrategy

        Method: getEmployees Return: []
        Method: addEmployee Args: (Santa Claus, 1 Reindeer Avenue, Lapland City - 25/12/1860) Return: true
        Method: getSalary Args: (Santa Claus, null - Birth date unknown) Return: 10000
        Method: getEmployees Return: [(Santa Claus, 1 Reindeer Avenue, Lapland City - 25/12/1860)]
        Method: isHiringFreeze Return: false
        Method: getEmployees Return: [(Santa Claus, 1 Reindeer Avenue, Lapland City - 25/12/1860)]
        Method: getSalaryStrategy

Copy to Clipboard

Toggle word wrap

To remove the auditing behavior, comment out the relevant fragments of XML in the deployment descriptor and restart the application.

Warning

The order of deployment matters. Specifically each aspect must be declared before the beans that it applies to, so that the Microcontainer deploys them in that order. This is because the Microcontainer may need to alter the bytecode of the normal bean class to add the cross-cutting logic, before it creates an instance and stores a reference to it in the controller. If a normal bean instance has already been created, this is not possible.

此内容没有您所选择的语言版本。

5.3. Applying An Aspect

学习

尝试、购买和销售

社区

关于红帽文档

让开源更具包容性

關於紅帽

Theme

Red Hat legal and privacy links

Red Hat legal and privacy links