spring获取bean

参考：百度安全验证

这里我列举2种方法，其它方法可以自行学习。

1、BeanUtils代码如下：

package com.hmblogs.backend.util;

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

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;

public class BeanUtils {

    public static Object getBean(Class clas){
        HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes()).getRequest();
        ServletContext servletContext = request.getSession().getServletContext();
        ApplicationContext ac = WebApplicationContextUtils.getWebApplicationContext(servletContext);
        return ac.getBean(clas);
    }
}

2、SpringUtils代码如下：

package com.hmblogs.backend.util;

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

@Component
public class SpringUtils implements ApplicationContextAware {

    private static ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        SpringUtils.applicationContext = applicationContext;
    }
    public static <T> T getBeanByName(String beanName) {
        if(applicationContext.containsBean(beanName)){
            return (T) applicationContext.getBean(beanName);
        }else{
            return null;
        }
    }
    public static <T> T getBeanByClass(Class<T> className) {
        T result = (T) applicationContext.getBean(className);
        return result;
    }

}

3、验证，测试类代码如下：

package com.hmblogs.backend.util;

import com.hmblogs.backend.entity.Blog;
import com.hmblogs.backend.service.BlogServiceImpl;
import com.hmblogs.backend.service.StockServiceImpl;
import lombok.extern.slf4j.Slf4j;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@Slf4j
//@Component
@RunWith(SpringRunner.class)
@SpringBootTest
public class BeanTest {

    @Test
    public void testBean() {
        // 请求参数
        BlogServiceImpl blogServiceImpl = (BlogServiceImpl) BeanUtils.getBean(BlogServiceImpl.class);
        Blog blog = new Blog();
        blog.setBlogTitle("xxxxxxx");
        blog.setBlogContent("fdsafadsfadsfdasf");
        blogServiceImpl.addBlog(blog);
    }

    @Test
    public void testBean22() {
        // 请求参数
        BlogServiceImpl blogServiceImpl = (BlogServiceImpl) SpringUtils.getBeanByClass(BlogServiceImpl.class);
        Blog blog = new Blog();
        blog.setBlogTitle("222222222");
        blog.setBlogContent("22222sasadsdas");
        blogServiceImpl.addBlog(blog);
    }
}