自定义注解之参数去空格

import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target;

/** * <p>对请求参数所有的字符串参数剔除空格</p> * <p>将传递的空字符串参数改成null</p> * <p>注意：请求参数模型需要提供构造方法</p> * <p>方便fastJOSN读写</p> * <p>不需要修改的参数将参数名放到excludes数组中</p> */ @Retention(RetentionPolicy.RUNTIME) @Target({ElementType.METHOD}) public @interface Trim {

/** * 不需要剔除空格的参数名集合 */ String[] excludes() default {}; }

package com.paic.phucp.console.aop;

import com.alibaba.fastjson.JSON; import com.alibaba.fastjson.JSONArray; import com.alibaba.fastjson.JSONObject; import com.paic.phucp.console.annotations.Trim; import lombok.extern.slf4j.Slf4j; import org.apache.commons.lang.StringUtils; import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.annotation.Around; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.annotation.Pointcut; import org.aspectj.lang.reflect.MethodSignature; import org.springframework.stereotype.Component;

import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import java.util.Arrays; import java.util.List; import java.util.Map;

/** * 切面：对使用@Trim自定义注解的接口剔除其中的参数值的前后空格 */ @Slf4j @Aspect @Component public class TrimAop {

@Pointcut("@annotation(com.paic.phucp.console.annotations.Trim)") public void trim() { // this is aop pointcut }

@Around("trim()") public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable { MethodSignature signature = (MethodSignature) proceedingJoinPoint.getSignature(); Trim trim = signature.getMethod().getAnnotation(Trim.class); if (null == trim) { return proceedingJoinPoint.proceed(); } Object[] args = proceedingJoinPoint.getArgs(); if (null == args || args.length == 0) { return proceedingJoinPoint.proceed(args); } List<String> excludeParams = Arrays.asList(trim.excludes()); for (int i = 0; i < args.length; i++) { if (args[i] instanceof ServletRequest || args[i] instanceof ServletResponse) { continue; } if (canBeParsed(JSON.toJSONString(args[i]))) { Class<?> type = args[i].getClass(); Object result = jsonLoop(JSON.parseObject(JSON.toJSONString(args[i])), excludeParams); args[i] = JSON.parseObject(JSON.toJSONString(result), type); } } return proceedingJoinPoint.proceed(args); }

/** * JSON 循环解析 */ private Object jsonLoop(Object object, List<String> excludeParams) { if (null == object) { return null; } if (object instanceof JSONObject) { JSONObject jsonObject = (JSONObject) object; for (Map.Entry<String, Object> entry : jsonObject.entrySet()) { parse(excludeParams, jsonObject, entry.getKey(), entry.getValue()); } } if (object instanceof JSONArray) { JSONArray jsonArray = (JSONArray) object; for (Object element : jsonArray) { jsonLoop(element, excludeParams); } } return object; }

/** * json解析 */ private void parse (List<String> excludeParams, JSONObject jsonObject, String key, Object value) { if (excludeParams.contains(key) || null == value){ return; } if (value instanceof String) { if (StringUtils.isBlank(value.toString())){ jsonObject.put(key, null); } else { jsonObject.put(key, value.toString().trim()); } } else if (value instanceof JSONArray || value instanceof JSONObject){ jsonLoop(value, excludeParams); } else { log.debug("nothing to do"); } }

/** * 是否能够被fastJSON 解析 * @param str 被解析的字符串 */ private boolean canBeParsed(String str) { try { JSON.parseObject(str); } catch (Exception e) { return false; } return true; } }