登录情况下任何地方获取用户ID

Controller层自定义注解配上拦截器可以自动封装，但是比较复杂，且仅限于控制层。这里尝试了另一种，可以直接从Spring上下文中获取。

预先获取Spring上下文存于容器中：

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

@Component
public class ApplicationContextRegister implements ApplicationContextAware {

    private static ApplicationContext APPLICATION_CONTEXT;

    static ApplicationContext getApplicationContext() {
        return APPLICATION_CONTEXT;
    }

    /**
     * 设置spring上下文
     *
     * @param applicationContext spring上下文
     * @throws BeansException
     */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        APPLICATION_CONTEXT = applicationContext;
    }
}

操作上下文工具类：

import java.util.Objects;

import javax.servlet.http.HttpServletRequest;

import org.springframework.context.ApplicationContext;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

/**
 * Spring Application 工具类
 *
 * @author Caratacus
 */
public class ApplicationUtils {

    /**
     * 全局的ApplicationContext
     */
    private final static ApplicationContext applicationContext = ApplicationContextRegister.getApplicationContext();

    /**
     * 获取ApplicationContext
     */
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }

    /**
     * 获取springbean
     *
     * @param beanName
     * @param requiredType
     * @param <T>
     * @return
     */
    public static <T> T getBean(String beanName, Class<T> requiredType) {
        if (containsBean(beanName)) {
            return applicationContext.getBean(beanName, requiredType);
        }
        return null;
    }

    /**
     * 获取springbean
     *
     * @param requiredType
     * @param <T>
     * @return
     */
    public static <T> T getBean(Class<T> requiredType) {
        return applicationContext.getBean(requiredType);
    }

    /**
     * 获取springbean
     *
     * @param beanName
     * @param <T>
     * @return
     */
    public static <T> T getBean(String beanName) {
        if (containsBean(beanName)) {
            Class<T> type = getType(beanName);
            return applicationContext.getBean(beanName, type);
        }
        return null;
    }

    /**
     * 依赖spring框架获取HttpServletRequest
     *
     * @return HttpServletRequest
     */
    public static HttpServletRequest getRequest() {
        HttpServletRequest request = null;
        try {
            ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
            if (Objects.nonNull(requestAttributes)) {
                request = requestAttributes.getRequest();
            }
        } catch (Exception ignored) {
        }
        return request;
    }

    /**
     * ApplicationContext是否包含该Bean
     *
     * @param name
     * @return
     */
    public static boolean containsBean(String name) {
        return applicationContext.containsBean(name);
    }

    /**
     * ApplicationContext该Bean是否为单例
     *
     * @param name
     * @return
     */
    public static boolean isSingleton(String name) {
        return applicationContext.isSingleton(name);
    }

    /**
     * 获取该Bean的Class
     *
     * @param name
     * @return
     */
    public static <T> Class<T> getType(String name) {
        return (Class<T>) applicationContext.getType(name);
    }

}

获取用户信息（UID）

import java.util.Objects;

import org.crown.common.spring.ApplicationUtils;
import org.crown.cons.APICons;
import org.crown.framework.emuns.ErrorCodeEnum;
import org.crown.framework.utils.ApiAssert;

import io.jsonwebtoken.Claims;
import lombok.AccessLevel;
import lombok.NoArgsConstructor;
import lombok.extern.slf4j.Slf4j;

/**
 * API工具类
 *
 * @author Caratacus
 */
@SuppressWarnings("ALL")
@NoArgsConstructor(access = AccessLevel.PRIVATE)
@Slf4j
public abstract class ApiUtils {

    /**
     * 获取当前用户id
     */
    public static Integer currentUid() {
        Integer uid = (Integer) ApplicationUtils.getRequest().getAttribute(APICons.API_UID);
        if (Objects.isNull(uid)) {
            String token = ApplicationUtils.getRequest().getHeader("Authorization");
            ApiAssert.notNull(ErrorCodeEnum.UNAUTHORIZED, token);
            token = token.replaceFirst("Bearer ", "");
            Claims claims = JWTUtils.getClaim(token);
            ApiAssert.notNull(ErrorCodeEnum.UNAUTHORIZED, claims);
            return claims.get(JWTUtils.UID, Integer.class);
        }
        return uid;
    }

}

：