Spring动态管理IoC容器中的Bean

来源：互联网发布：安全座椅选择知乎编辑：程序博客网时间：2024/06/06 06:40

以下为工具类，此工具类需要在Spring中注册。有动态获取Bean的方法，也有把Bean动态交给IoC容器管理的方法。可直接copy复用：实现接口：

org.springframework.context.ApplicationContextAware

实现该接口的setApplicationContext(ApplicationContext context)方法，并保存ApplicationContext 对象。Spring初始化时，会通过该方法将ApplicationContext 对象注入。

package com.xx.xx.util;import java.util.Map;import org.springframework.beans.MutablePropertyValues;import org.springframework.beans.factory.support.DefaultListableBeanFactory;import org.springframework.beans.factory.support.GenericBeanDefinition;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;import org.springframework.stereotype.Component;@Componentpublic class SpringContextHolder implements ApplicationContextAware {private static ApplicationContext applicationContext;/**     * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.     */    public void setApplicationContext(ApplicationContext applicationContext) {        SpringContextHolder.applicationContext =applicationContext;    }        /**     * 取得存储在静态变量中的ApplicationContext.     */    public static ApplicationContext getApplicationContext() {        checkApplicationContext();        return applicationContext;    }        /** * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型. */@SuppressWarnings("unchecked")public static <T> T getBean(String name) {checkApplicationContext();if (applicationContext.containsBean(name)) {return (T) applicationContext.getBean(name);}return null;}    /**     * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.     */    @SuppressWarnings("unchecked")    public static <T> T getBean(Class<T> clazz) {        checkApplicationContext();        return (T) applicationContext.getBeansOfType(clazz);    }    private static void checkApplicationContext() {        if (applicationContext == null)            throw new IllegalStateException("applicaitonContext未注入,请在applicationContext.xml中定义SpringContextUtil");    }        /** * 同步方法注册bean到ApplicationContext中 *  * @param beanName * @param clazz * @param original bean的属性值 */public static synchronized void setBean(String beanName, Class<?> clazz,Map<String,Object> original) {checkApplicationContext();DefaultListableBeanFactory beanFactory = (DefaultListableBeanFactory) applicationContext.getAutowireCapableBeanFactory();if(beanFactory.containsBean(beanName)){return;}//BeanDefinition beanDefinition = new RootBeanDefinition(clazz);GenericBeanDefinition definition = new GenericBeanDefinition();//类classdefinition.setBeanClass(clazz);//属性赋值definition.setPropertyValues(new MutablePropertyValues(original));//注册到spring上下文beanFactory.registerBeanDefinition(beanName, definition);}/** * 删除spring中管理的bean * @param beanName */public static void removeBean(String beanName){ApplicationContext ctx = SpringContextHolder.getApplicationContext();DefaultListableBeanFactory acf = (DefaultListableBeanFactory) ctx.getAutowireCapableBeanFactory();if(acf.containsBean(beanName)) {    acf.removeBeanDefinition(beanName);}}}

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