AOP主要注解:
@Aspect,作用在类上,说明这是一个Aspect切面类。
@Pointcut,用来描述,你需要在哪些类的哪些方法中植入你的代码。
@Adive,与Pointcut配合使用,主要说明在Pointcut标记方法的什么时机执行,执行之前?执行之后?
@Pointcut express(切面表达式)
designators指示器:
匹配方法:execution() 通过什么方式去匹配哪些类的哪些方法(重点掌握)。
匹配注解:@annotation() @args() @within() @target()
匹配包/类型:within()
匹配对象:this() bean() target()
匹配参数:args()
wildcards通配符:
* 匹配任意数量的字符
.. 匹配指定类及其子类
+ 匹配任意数的子包或参数
operators运算符:&&与 ||或 !非
5中Advice
@Before
@After
@AfterReturning
@AfterThrowing
@Around
示例代码
@Aspect
@Component
public class HttpAspect {
private final static Logger logger = LoggerFactory.getLogger(HttpAspect.class);
@Pointcut("execution(public * com.imooc.controller.GirlController.*(..))")
public void log(){
}
/**
* 在截取的方法前执行
* @param joinPoint
*/
@Before("log()")
public void doBefore(JoinPoint joinPoint){
ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
HttpServletRequest request = attributes.getRequest();
// url
logger.info("url={}", request.getRequestURL());
// method
logger.info("method={}", request.getMethod());
// ip
logger.info("ip={}", request.getRemoteAddr());
// 类方法
logger.info("class_method={}", joinPoint.getSignature().getDeclaringTypeName() + "." + joinPoint.getSignature().getName());
// 参数
logger.info("args={}", joinPoint.getArgs());
}
/**
* 获取方法返回参数
* @param object
*/
@AfterReturning(returning = "object", pointcut = "log()")
public void doAfterReturning(Object object){
logger.info("response={}", object);
}
}
Advice示例
@Aspect
@Component
public class AdviceAspectConfig {
/********PointCut********/
@Pointcut("@annotation(com.vmware.AopExecutionDemo.annotation.AdminOnlyMethod)")
public void matchAnnotation(){}
@Pointcut("execution(* com.vmware.AopExecutionDemo.service.*.find*(int))")
public void matchIntArgs(){}
@Pointcut("execution(public * com.vmware.AopExecutionDemo.service..*.*(..) throws java.lang.IllegalAccessException)")
public void matchExecption(){}
@Pointcut("execution(int com.vmware.AopExecutionDemo.service.*.*(..))")
public void matchReturn(){}
/********Advice********/
/**
* 获取方法输入的参数
* @param productId
*/
@Before("matchIntArgs() && args(productId)")
public void before(int productId){
System.out.println("### before ### productId = [" + productId + "]");
}
/**
* 获取方法返回参数
* @param result
*/
@AfterReturning(value = "matchReturn()", returning = "result")
public void after(int result){
System.out.println("### after ###:" + result);
}
/**
* Before + After + AfterReturning
* @param joinPoint
* @return
* @throws Throwable
*/
@Around("matchReturn()")
public Object after(ProceedingJoinPoint joinPoint) throws Throwable {
System.out.println("### before ###");
Object result;
result = joinPoint.proceed(joinPoint.getArgs());
System.out.println("### after ###" + result);
return result;
}
}
@annotation示例
@Aspect
@Component
public class AnnotationAspectConfig {
/**
* 匹配带有 AdminOnlyMethod Annotation的方法
*/
@Pointcut("@annotation(com.vmware.AopExecutionDemo.annotation.AdminOnlyMethod)")
public void matchAnnotation(){}
@Before("matchAnnotation()")
public void before(){
System.out.println("###matchAnnotation && Before");
}
}
@Aspect
@Component
public class AnnotationClassAspectConfig {
/**
* 匹配带有 AdminOnlyClass Annotation的类
*/
@Pointcut("@within(com.vmware.AopExecutionDemo.annotation.AdminOnlyClass)")
public void annotationClassCondition(){}
@Before("annotationClassCondition()")
public void before(){
System.out.println("###annotationClass && before");
}
}