Spring AOP预处理Controller的参数

实际编程中，可能会有这样一种情况，前台传过来的参数，我们需要一定的处理才能使用

比如有这样一个Controller

@Controller
public class MatchOddsController {
    @Autowired
    private MatchOddsServcie matchOddsService;
    @RequestMapping(value = "/listOdds", method = RequestMethod.GET, produces = {MediaType.APPLICATION_JSON_VALUE})
    @ResponseBody
    public List listOdds(@RequestParam Date startDate, @RequestParam Date endDate) {
        return matchOddsService.listOdds(startDate, endDate);
    }
}

前台传过来的startDate和endDate是两个日期，实际使用中我们需要将之转换为两个日期对应的当天11点，如果只有这么一个类的话，我们是可以直接在方法最前面处理就可以了

但是，还有下面两个类具有同样的业务逻辑

@Controller
public class MatchProductController {
    @Autowired
    private MatchProductService matchProductService;
    @RequestMapping(value = "/listProduct", method = RequestMethod.GET, produces = { MediaType.APPLICATION_JSON_VALUE })
    @ResponseBody
    public List listProduct(@RequestParam Date startDate, @RequestParam Date endDate) {
        return matchProductService.listMatchProduct(startDate, endDate);
    }
}

@Controller
public class MatchController {
    @Autowired
    private MatchService matchService;
    
    @RequestMapping(value = "/listMatch", method = RequestMethod.GET, produces = {MediaType.APPLICATION_JSON_VALUE})
    @ResponseBody
    public List listMatch(@RequestParam Date startDate, @RequestParam Date endDate) {
        return matchService.listMatch(startDate, endDate);
    }
}

当然也可以写两个util方法，分别处理startDate和endDate，但是为了让Controller看起来更干净一些，我们还是用AOP来实现吧，顺便为AOP更复杂的应用做做铺垫

本应用中使用Configuration Class来进行配置，

主配置类如下：

@SpringBootApplication
@EnableAspectJAutoProxy(proxyTargetClass = true) //开启AspectJ代理，并将proxyTargetClass置为true，表示启用cglib对Class也进行代理
public class Application extends SpringBootServletInitializer {
    ...
}

下面新建一个Aspect类，代码如下

@Aspect //1
@Configuration //2
public class SearchDateAspect {
    @Pointcut("execution(* com.ronnie.controller.*.list*(java.util.Date,java.util.Date)) && args(startDate,endDate)") //3
    private void searchDatePointcut(Date startDate, Date endDate) { //4
    }
    @Around(value = "searchDatePointcut(startDate,endDate)", argNames = "startDate,endDate") //5
    public Object dealSearchDate(ProceedingJoinPoint joinpoint, Date startDate, Date endDate) throws Throwable { //6
        Object[] args = joinpoint.getArgs(); //7
        if (args[0] == null) {
            args[0] = Calendars.getTodayEleven();
            args[1] = DateUtils.add(new Date(), 7, TimeUnit.DAYS);//默认显示今天及以后的所有赔率
        } else {
            args[0] = DateUtils.addHours(startDate, 11);
            args[1] = DateUtils.addHours(endDate, 11);
        }
        return joinpoint.proceed(args); //8
    }
}

分别解释一下上面各个地方的意思，标号与语句之后的注释一致

更多可参考

http://docs.spring.io/spring/docs/current/spring-framework-reference/html/aop.html

http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/

AOP获取参数名称

由于项目中打印日志的需要，研究了一下在aop中，获取参数名称的方法。

1、jdk1,8中比较简单，直接通过joinPoint中的getSignature()方法即可获取

Signature signature = joinpoint.getSignature();  
MethodSignature methodSignature = (MethodSignature) signature;  
String[] strings = methodSignature.getParameterNames();  
System.out.println(Arrays.toString(strings));  

2.通用方法。比较麻烦

public Object logAround(ProceedingJoinPoint joinPoint) throws Throwable{  
          
        String classType = joinPoint.getTarget().getClass().getName();    
        Class<?> clazz = Class.forName(classType);    
        String clazzName = clazz.getName();    
        String methodName = joinPoint.getSignature().getName(); //获取方法名称   
        Object[] args = joinPoint.getArgs();//参数  
          //获取参数名称和值  
        Map nameAndArgs = getFieldsName(this.getClass(), clazzName, methodName,args);   
        System.out.println(nameAndArgs.toString());  
        //为了省事，其他代码就不写了，  
        return result = joinPoint.proceed();  
   
}  

private Map getFieldsName(Class cls, String clazzName, String methodName, Object[] args) throws NotFoundException {   
        Map map=new HashMap();  
          
        ClassPool pool = ClassPool.getDefault();    
        //ClassClassPath classPath = new ClassClassPath(this.getClass());    
        ClassClassPath classPath = new ClassClassPath(cls);    
        pool.insertClassPath(classPath);    
            
        CtClass cc = pool.get(clazzName);    
        CtMethod cm = cc.getDeclaredMethod(methodName);    
        MethodInfo methodInfo = cm.getMethodInfo();  
        CodeAttribute codeAttribute = methodInfo.getCodeAttribute();    
        LocalVariableAttribute attr = (LocalVariableAttribute) codeAttribute.getAttribute(LocalVariableAttribute.tag);    
        if (attr == null) {    
            // exception    
        }    
       // String[] paramNames = new String[cm.getParameterTypes().length];    
        int pos = Modifier.isStatic(cm.getModifiers()) ? 0 : 1;    
        for (int i = 0; i < cm.getParameterTypes().length; i++){    
            map.put( attr.variableName(i + pos),args[i]);//paramNames即参数名    
        }    
          
        //Map<>  
        return map;    
    } 

以上为个人经验，希望能给大家一个参考，也希望大家多多支持趣讯吧。