Spring手动创建bean并注册工具类SpringBeanUtil

import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractRefreshableApplicationContext;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.type.classreading.CachingmetadataReaderFactory;
import org.springframework.core.type.classreading.metadataReader;
import org.springframework.core.type.classreading.metadataReaderFactory;
import org.springframework.util.ClassUtils;

import java.io.IOException;
import java.lang.annotation.Annotation;
import java.util.HashMap;
import java.util.Map;


public class SpringBeanUtil {

    public static Object registerSingletonBean(ApplicationContext ctx, String beanName, Object singletonObject) {
        DefaultListableBeanFactory beanFactory = (DefaultListableBeanFactory)ctx.getAutowireCapableBeanFactory();
        beanFactory.registerSingleton(beanName, singletonObject);
        return ctx.getBean(beanName);
    }

    public static boolean addBean(ApplicationContext ctx, String beanName, Class beanClass, Object... constructValues) {
        BeanDefinitionRegistry beanDefReg = (DefaultListableBeanFactory)((AbstractRefreshableApplicationContext)ctx).getBeanFactory();
        if(beanDefReg.containsBeanDefinition(beanName)) {
            return false;
        }
        BeanDefinitionBuilder beanDefBuilder = BeanDefinitionBuilder.genericBeanDefinition(beanClass);
        for (Object constructValue : constructValues) {
            beanDefBuilder.addConstructorArgValue(constructValue);
        }
        BeanDefinition beanDefinition = beanDefBuilder.getBeanDefinition();
        beanDefReg.registerBeanDefinition(beanName, beanDefinition);
        return true;
    }

    public static void removeBean(ApplicationContext ctx, String beanName) {
        BeanDefinitionRegistry beanDefReg = (DefaultListableBeanFactory)((AbstractRefreshableApplicationContext)ctx).getBeanFactory();
        beanDefReg.removeBeanDefinition(beanName);
    }

    private static final String RESOURCE_PATTERN = "*.class";

    public static Map findAllClass(String basePackage, Class cls) {
        Map handlerMap = new HashMap<>();

        //spring工具类，可以获取指定路径下的全部类
        ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
        try {
            String pattern = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX +
                    ClassUtils.convertClassNameToResourcePath(basePackage) + RESOURCE_PATTERN;
            Resource[] resources = resourcePatternResolver.getResources(pattern);
            //metadataReader 的工厂类
            metadataReaderFactory readerfactory = new CachingmetadataReaderFactory(resourcePatternResolver);
            for (Resource resource : resources) {
                //用于读取类信息
                metadataReader reader = readerfactory.getmetadataReader(resource);
                //扫描到的class
                String classname = reader.getClassmetadata().getClassName();
                Class clazz = Class.forName(classname);
                if(cls.isAnnotation()) {
                    Object anno = clazz.getAnnotation(cls);
                    if (anno != null) {
                        handlerMap.put(clazz.getSimpleName(), clazz);
                    }
                }else if(cls.isAssignableFrom(clazz)) {
                    handlerMap.put(clazz.getSimpleName(), clazz);
                }
            }
        } catch (IOException | ClassNotFoundException e) {
        }
        return handlerMap;
    }
}