SpringBoot动态创建Bean

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SpringBoot测试版本：1.3.4.RELEASE

参考代码如下：

package com.spring.configuration;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.beans.factory.support.BeanDefinitionBuilder;import org.springframework.beans.factory.support.DefaultListableBeanFactory;import org.springframework.boot.autoconfigure.condition.ConditionalOnExpression;import org.springframework.context.ApplicationContext;import org.springframework.context.ConfigurableApplicationContext;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.jdbc.core.JdbcTemplate;@Configuration/** * 这里的conditional是一个可选条件，表示当这个表达式为true的时候，才动态创建bean */@ConditionalOnExpression("${my.configuration.enabled}")public class DynamicConfiguration{@Autowiredprivate ApplicationContext applicationContext;/** * 这个方法返回Runnable只是一个幌子，最重要的是执行方法里面的代码 */@Beanpublic Runnable dynamicConfiguration() throws Exception{ConfigurableApplicationContext context = (ConfigurableApplicationContext)applicationContext;DefaultListableBeanFactory beanFactory = (DefaultListableBeanFactory)context.getBeanFactory();BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder.rootBeanDefinition(UserService.class);/** * 设置属性 */beanDefinitionBuilder.addPropertyValue("name", "myConfigure");beanDefinitionBuilder.addPropertyValue("jdbcTemplate", applicationContext.getBean(JdbcTemplate.class));/** * 注册到spring容器中 */beanFactory.registerBeanDefinition("userService", beanDefinitionBuilder.getBeanDefinition());return null;}}class UserService{private String name;private JdbcTemplate jdbcTemplate;public String getName(){return name;}public void setName(String name){this.name = name;}public JdbcTemplate getJdbcTemplate(){return jdbcTemplate;}public void setJdbcTemplate(JdbcTemplate jdbcTemplate){this.jdbcTemplate = jdbcTemplate;}}

之后，就可以使用如下方式获取对象了
applicationContext.getBean(UserService.class);
applicationContext.getBean("userService", UserService.class)

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