注解

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

/**
 * 自动设置创建人
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface CreateBy {
    String value() default "";
}
/**
 * 自动设置创建时间
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface CreateTime {
    String value() default "";
}
/**
 * 自动设置修改人
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface UpdateBy {
    String value() default "";
}
/**
 * 自动设置修改时间
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface UpdateTime {
    String value() default "";
}

拦截器

import org.apache.ibatis.binding.MapperMethod;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.SqlCommandType;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Signature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Field;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/**
 * 自定义 Mybatis 插件，自动设置 createTime 和 updatTime 的值。
 * 拦截 update 操作（添加和修改）
 */
@Component
@Intercepts({@Signature(type = Executor.class, method = "update", args = {MappedStatement.class, Object.class})})
public class CustomInterceptor implements Interceptor {
    private static final Logger logger = LoggerFactory.getLogger(CustomInterceptor.class);

    @Override
    public Object intercept(Invocation invocation) throws Throwable {
        MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0];

        // 获取 SQL 命令
        SqlCommandType sqlCommandType = mappedStatement.getSqlCommandType();
        //只判断新增和修改
        if (SqlCommandType.INSERT.equals(sqlCommandType) || SqlCommandType.UPDATE.equals(sqlCommandType)) {
            // 获取参数
            Object parameter = invocation.getArgs()[1];
            //批量操作时
            if (parameter instanceof MapperMethod.ParamMap) {
                MapperMethod.ParamMap map = (MapperMethod.ParamMap) parameter;
                Object obj = map.get("list");
                List<?> list = (List<?>) obj;
                if (list != null) {
                    for (Object o : list) {
                        setParameter(o, sqlCommandType);
                    }
                }
            } else {
                setParameter(parameter, sqlCommandType);
            }
        }
        return invocation.proceed();
    }

    public void setParameter(Object parameter, SqlCommandType sqlCommandType) throws Throwable {
        Class<?> aClass = parameter.getClass();
        Field[] declaredFields;
        //如果常用字段提取了公共类 BaseEntity
        //判断BaseEntity是否是父类
        if (BaseEntity.class.isAssignableFrom(aClass)) {
        // 获取父类私有成员变量
            declaredFields = aClass.getSuperclass().getDeclaredFields();
        } else {
            // 获取私有成员变量
            declaredFields = aClass.getDeclaredFields();
        }
        for (Field field : declaredFields) {
            if (SqlCommandType.INSERT.equals(sqlCommandType)) { // insert 语句插入 createBy
                if (field.getAnnotation(CreateBy.class) != null) {
                    field.setAccessible(true);
                    field.set(parameter, SecurityUtils.getUsername());
                }

                if (field.getAnnotation(CreateTime.class) != null) { // insert 语句插入 createTime
                    field.setAccessible(true);
                    field.set(parameter, new Timestamp(System.currentTimeMillis()));
                }
            }

            if (SqlCommandType.UPDATE.equals(sqlCommandType)) {
                if (field.getAnnotation(UpdateTime.class) != null) { // update 语句插入 updateTime
                    field.setAccessible(true);
                    field.set(parameter, new Timestamp(System.currentTimeMillis()));
                }
                if (field.getAnnotation(UpdateBy.class) != null) { // update 语句插入 updateBy
                    field.setAccessible(true);
                    field.set(parameter, SecurityUtils.getUsername());
                }
            }
        }
    }
}

变量上添加注解

public class BaseEntity implements Serializable {

    /**
     * 创建者
     */
    @CreateBy
    private String createBy;

    /**
     * 创建时间
     */
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+8")
    @CreateTime
    private Date createTime;
    }
    @UpdateBy
    private String updateBy;

    /**
     * 更新时间
     */
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss" , timezone = "GMT+8")
    @UpdateTime
    private Date updateTime;

保存当前线程变量

import com.alibaba.ttl.TransmittableThreadLocal;
import com.yjt.common.core.constant.SecurityConstants;
import com.yjt.common.core.text.Convert;
import com.yjt.common.core.utils.StringUtils;

import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;


public class SecurityContextHolder
{
    private static final TransmittableThreadLocal<Map<String, Object>> THREAD_LOCAL = new TransmittableThreadLocal<>();

    public static void set(String key, Object value)
    {
        Map<String, Object> map = getLocalMap();
        map.put(key, value == null ? StringUtils.EMPTY : value);
    }

    public static String get(String key)
    {
        Map<String, Object> map = getLocalMap();
        return Convert.toStr(map.getOrDefault(key, StringUtils.EMPTY));
    }

    public static <T> T get(String key, Class<T> clazz)
    {
        Map<String, Object> map = getLocalMap();
        return StringUtils.cast(map.getOrDefault(key, null));
    }

    public static Map<String, Object> getLocalMap()
    {
        Map<String, Object> map = THREAD_LOCAL.get();
        if (map == null)
        {
            map = new ConcurrentHashMap<String, Object>();
            THREAD_LOCAL.set(map);
        }
        return map;
    }

    public static void setLocalMap(Map<String, Object> threadLocalMap)
    {
        THREAD_LOCAL.set(threadLocalMap);
    }

    public static String getUserName()
    {
        return get("username");
    }

    public static void setUserName(String username)
    {
        set("username", username);
    }

    public static void remove()
    {
        THREAD_LOCAL.remove();
    }
}

拦截器

public class HeaderInterceptor implements AsyncHandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
//通过request获取到当前访问用户信息 在设置进线程变量中
       SecurityContextHolder.setUserName("获取到的用户名称");
        return true;
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
            throws Exception {
        SecurityContextHolder.remove();
    }
}

获取用户信息工具类
public class SecurityUtils
{
/**
* 获取用户名称
*/
public static String getUsername()
{
return SecurityContextHolder.getUserName();
}
}