spring boot --- 注解 @Bean 和@Component

1.前言

@Bean是给方法注册bean

@Component是给不好归类的类注册bean

2.可以达到一样的效果

（1）@Component 直接注册即可

 完整源码 

package com.example.demomycenzuul.myFilter;


import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import org.apache.commons.lang.StringUtils;

import org.slf4j.LoggerFactory;
import org.springframework.cloud.netflix.zuul.filters.support.FilterConstants;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;
import java.util.logging.Logger;


@Component
public class AccessFilter extends ZuulFilter {

    @Override
    public String filterType() {
        return FilterConstants.PRE_TYPE;
    }

    @Override
    public int filterOrder() {
        return 0;
    }

    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() {
        System.out.println("进入zuul拦截");
        //获取上下文
        RequestContext ctx = RequestContext.getCurrentContext();
        //获取Request
        HttpServletRequest request = ctx.getRequest();
        //获取请求参数accessToken
        String accessToken = request.getParameter("accessToken");
        //使用String工具类
        if (StringUtils.isBlank(accessToken)) {
            ctx.setSendZuulResponse(false);  //进行拦截
            ctx.setResponseStatusCode(401);
            try {
                ctx.getResponse().getWriter().write("accessToken is empty,-------401");
            } catch (Exception e) {
            }
            return null;
        }
        return null;
    }

}

 （2）@bean则不需要在类加注解

 但是，需要去启动类new这个类