日志

日志在开发中必不可少，方便记录代码执行过程、排查问题。下面是两种日志的使用

1、日志切面：通过切面记录请求参数和响应结果

2、log日志：记录正常信息（log.info），错误信息（log.error、log.warn）

1、日志切面

package com.xxx.datamanager.aop;

import lombok.extern.slf4j.Slf4j;
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.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * @author 
 * @说明：日志切面
 * @create 
 */
@Aspect
@Component
@Slf4j
public class AccessLog {

    @Pointcut("execution(public * com..xxx.datamanager.controller.*.*(..))")
    public void log() {
    }

    @Around("log()")
    public Object doAround(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
        long start = System.currentTimeMillis();
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();

        Map<String, String> requestInfo = new HashMap<>();
        requestInfo.put("remoteIp", request.getRemoteAddr());
        requestInfo.put("httpMethod", request.getMethod());
        requestInfo.put("requestUrl", request.getRequestURL().toString());
        Object[] args = proceedingJoinPoint.getArgs();
        Map<String, String[]> parameterMap = request.getParameterMap();
        if (parameterMap.size() == 0 && args.length > 0) {
            requestInfo.put("requestParam", JSONObject.valueToString(getKeyAndValue(args[0])));
        } else {
            requestInfo.put("requestParam", JSONObject.valueToString(parameterMap));
        }
        log.info(LogFormat.build().putTags(requestInfo).message("请求信息"));

        Map<String, String> responseInfo = new HashMap<>();
        Object result = proceedingJoinPoint.proceed();
        responseInfo.put("response", new JSONObject(result).toString());
        responseInfo.put("timeCost", (System.currentTimeMillis() - start) + "ms");
        log.info(LogFormat.build().putTags(responseInfo).message("响应信息"));
        return result;
    }

    public static Map<String, Object> getKeyAndValue(Object object) throws IllegalAccessException {
        Map<String, Object> parameMap = new HashMap<>();
        if (null == object) return parameMap;
        Field[] fields = object.getClass().getDeclaredFields();
        for (Field field : fields) {
            field.setAccessible(true);
            if (field.get(object) == null) continue;
            parameMap.put(field.getName(), field.get(object));
        }
        return parameMap;
    }
}

2、log.info/log.error——@Slf4j

log.info、log.error、log.warn 中支持占位符，如log.info("打印 {}，{}", v1, v2)；

当只有一个参数时，占位符不生效（只要将异常信息作为最后一个参数即可，不论使用还是不使用占位符，都不会影响异常信息的输出，只不过占位符不会生效）

// log.info：用于记录查库信息 / rpc调用结果 / 需要打印的重要信息，在方法中直接使用log.info
List<Integer> datasetIds = datasetAccessMapper.selectByMisId(misId, startFrom, size);
log.info(">>>> datasetIds: {}", JsonUtils.toJson(datasetIds));

//log.error：用于记录报错信息，可用于try catch异常中/全局异常处理
package com.xxx.exception;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
@Slf4j
@ControllerAdvice
public class GlobalExceptionHandler {
    @ExceptionHandler(Exception.class)
    private ResponseEntity<?> handleUnknownException(Exception e) {
        log.error("服务异常：", e);        //日志记录
        return ResponseEntity.status(HttpStatus.OK).body(Response.error(INTERNAL_ERROR));    //返回结果
    }
}