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Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'App' is defined

2024-09-01 13:44:58   219人阅读

工具：Eclipse mars

环境：jdk1.8

说明：这是在学习Spring Task时遇到的一个bug，代码如下：

定时任务类：

package com.task.test;

import java.util.Date;
import org.springframework.stereotype.Component;

@Component
public class App {

    public void execute1(){
        System.out.printf("Task: %s, Current time: %s\n", 1, new Date() +" current thread :" +Thread.currentThread().getName());
    }

    public void execute2(){
        System.out.printf("Task: %s, Current time: %s\n", 2, new Date() +" current thread :" +Thread.currentThread().getName());
    }

}

Spring配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:task="http://www.springframework.org/schema/task"
       xsi:schemaLocation="
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.1.xsd
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd
            http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-4.1.xsd">

    <!-- 配置注解扫描 -->
    <context:component-scan base-package="com.task.test"/>

    <task:scheduler id="taskScheduler" pool-size="100" />

    <task:scheduled-tasks scheduler="taskScheduler">
        <!-- 即刻开始隔5秒钟触发任务一次 -->
        <task:scheduled ref="App" method="execute1" cron="0/5 * * * * ?"/>
        <!-- 即刻开始，隔10秒钟触发任务一次 -->
        <task:scheduled ref="App" method="execute2" cron="0/10 * * * * ?"/>
    </task:scheduled-tasks>

</beans>

测试代码：

package com.task.test;

import java.util.Date;
import org.springframework.stereotype.Component;

@Component
public class App {

    public void execute1(){
        System.out.printf("Task: %s, Current time: %s\n", 1, new Date() +" current thread :" +Thread.currentThread().getName());
    }

    public void execute2(){
        System.out.printf("Task: %s, Current time: %s\n", 2, new Date() +" current thread :" +Thread.currentThread().getName());
    }

}

 

操作：右键Eclipse编辑区--->点击Run As--->Java Application

报错：

技术分享

原因：spring配置文件中的 ref 属性值得命名格式应该是驼峰命名法，即将spring配置文件中的ref="App"改为ref="app"即可。

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'App' is defined


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