Spring动态修改bean属性的value

小鱼儿 2024-04-08 11:53 81阅读 0赞

1、定义成员变量

package com.example.demo.controller;
    
    import com.example.demo.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.core.env.Environment;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.bind.annotation.RestController;
    
    import java.io.IOException;
    import java.util.Map;
    
    /**
     * @Description: TODO
     * @Author: Top
     * @Version: V1.0
     * @Date: 2020-01-15 15:03
     */
    @RestController
    @RequestMapping("/api/{edition}/page2")
    public class MyPageHelperController2 {
        
    
        @Autowired
        private Environment env;
    
        @Autowired
        private UserService userServiceImpl;
    
        private String str1;
    
        private static String str2;
    
        @GetMapping("/myPage3")
        @ResponseBody
        public Map<Object, Object> expenseStatement(Object str) throws IOException {
        
    
            str1 = "zhangjiguo";
            System.out.println(str1);
    
            str2 = "guoguo";
            System.out.println(str2);
            return null;
        }
    
        @GetMapping("/myPage4")
        @ResponseBody
        public Map<Object, Object> expenseStatement2(Object str) throws IOException {
        
    
            System.out.println(str1);
            System.out.println(str2);
    
            return null;
        }
    
        @GetMapping("/myPage5")
        @ResponseBody
        public Map<Object, Object> expenseStatement3(Object str) throws IOException {
        
    
            str1 = "zhangsan";
            str2 = "jiji";
            System.out.println(str1);
            System.out.println(str2);
    
            return null;
        }
    }

2、定义工具类，从容器中获取某个bean

package com.example.demo.common;
    
    import org.springframework.beans.BeansException;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.ApplicationContextAware;
    import org.springframework.stereotype.Component;
    
    @Component
    public class SpringContextUtils implements ApplicationContextAware {
        
    
        private static ApplicationContext applicationContext;
    
        /**
         * 通过name获取 Bean.
         *
         * @param name
         * @return
         */
        public static Object getBean(String name) {
        
            return getApplicationContext().getBean(name);
        }
    
        /**
         * 通过class获取Bean.
         *
         * @param clazz
         * @param <T>
         * @return
         */
        public static <T> T getBean(Class<T> clazz) {
        
            return getApplicationContext().getBean(clazz);
        }
    
        /**
         * 通过name及Clazz返回指定的Bean
         *
         * @param name
         * @param clazz
         * @param <T>
         * @return
         */
        public static <T> T getBean(String name, Class<T> clazz) {
        
            return getApplicationContext().getBean(name, clazz);
        }
    
        @Autowired
        public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        
            SpringContextUtils.applicationContext = applicationContext;
        }
    
        /**
         * 获取applicationContext
         *
         * @return
         */
        public static ApplicationContext getApplicationContext() {
        
            return applicationContext;
        }
    }

3、修改成员变量

@RequestMapping("ok")
        public Object test2(){
        
            ApplicationContext applicationContext = SpringContextUtils.getApplicationContext();
            String[] beans = applicationContext.getBeanDefinitionNames();
            for (String beanName : beans) {
        
                // 拿到bean的Class对象
                Class<?> beanType = applicationContext.getType(beanName);
                if (beanType == null) {
        
                    continue;
                }
                // 拿到当前bean类型的所有字段
                Field[] declaredFields = beanType.getDeclaredFields();
                if(!beanName.contains("myPageHelperController2") ){
        
                    continue;
                }
                for (Field field : declaredFields) {
        
                    // 从spring容器中拿到这个具体的bean对象
                    Object bean = applicationContext.getBean(beanName);
                    // 当前字段设置新的值
                    try {
        
                        setFieldData(field, bean, "ffffff");
                        System.out.println("finished");
                    } catch (Exception e) {
        
                        e.printStackTrace();
                    }
                }
            }
            return "ok";
        }
    
        private void setFieldData(Field field, Object bean, String data) throws Exception {
        
            // 注意这里要设置权限为true
            field.setAccessible(true);
            Class<?> type = field.getType();
            if (type.equals(String.class)) {
        
                field.set(bean, data);
            } else if (type.equals(Integer.class)) {
        
                field.set(bean, Integer.valueOf(data));
            } else if (type.equals(Long.class)) {
        
                field.set(bean, Long.valueOf(data));
            } else if (type.equals(Double.class)) {
        
                field.set(bean, Double.valueOf(data));
            } else if (type.equals(Short.class)) {
        
                field.set(bean, Short.valueOf(data));
            } else if (type.equals(Byte.class)) {
        
                field.set(bean, Byte.valueOf(data));
            } else if (type.equals(Boolean.class)) {
        
                field.set(bean, Boolean.valueOf(data));
            } else if (type.equals(Date.class)) {
        
                field.set(bean, new Date(Long.valueOf(data)));
            }
        }