該篇提供了一個小的AOP應用案例:系統日誌

@Aspect
@Component
public class SysLogAspect {
    @Autowired
    private SysLogService sysLogService;
    
    @Pointcut("@annotation(io.renren.common.annotation.SysLog)")
    public void logPointCut() { 
        
    }

    @Around("logPointCut()")
    public Object around(ProceedingJoinPoint point) throws
 
 Throwable {
        long beginTime = System.currentTimeMillis();
        //執行方法
        Object result = point.proceed();
        //執行時長(毫秒)
        long time = System.currentTimeMillis() - beginTime;

        //儲存日誌
        saveSysLog(point, time);

        return result;
    }

    private void saveSysLog(ProceedingJoinPoint joinPoint, long
 
 time) {
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        Method method = signature.getMethod();

        SysLogEntity sysLog = new SysLogEntity();
        SysLog syslog = method.getAnnotation(SysLog.class);
        if(syslog != null){
            //註解上的描述
            sysLog.setOperation(syslog.value());
        }

        
 
//請求的方法名
        String className = joinPoint.getTarget().getClass().getName();
        String methodName = signature.getName();
        sysLog.setMethod(className + "." + methodName + "()");

        //請求的引數
        Object[] args = joinPoint.getArgs();
        try{
            String params = new Gson().toJson(args[0]);
            sysLog.setParams(params);
        }catch (Exception e){

        }

        //獲取request
        HttpServletRequest request = HttpContextUtils.getHttpServletRequest();
        //設定IP地址
        sysLog.setIp(IPUtils.getIpAddr(request));

        //使用者名稱
        String username = ((SysUserEntity) SecurityUtils.getSubject().getPrincipal()).getUsername();
        sysLog.setUsername(username);

        sysLog.setTime(time);
        sysLog.setCreateDate(new Date());
        //儲存系統日誌
        sysLogService.save(sysLog);
    }
}

此處切點logPointCut是附在註解io.renren.common.annotation.SysLog上的,

下面是註解SysLog:

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface SysLog {

    String value() default "";
}

切面程式碼中sysLogService無疑就是存入資料庫的操作了,寫持久層和建表這裡都不贅述了.

應用的話只要在Controller上所需要的方法貼上註解即可,value給上操作名稱