如何在 Intellij 中使用 bean 创建基本的 spring 应用程序

Question

I tried a basic and my first spring application using the Intellij IDEA community edition 2019.3.1. I passed the class argument to the main class using ApplicationContext, beans, and the XML file to parse the data value. But when running the application it shows a FileNotFound Exception, even though the XML file exists there. The below image shows my project structure.

Below are my codes from App.java and luxan.xml

package org.example;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App
{
    public static void main( String[] args )
    {
        ApplicationContext context = new ClassPathXmlApplicationContext("org/example/luxan.xml");
        Vehicle obj = (Vehicle)context.getBean("vehicle");
        obj.drive();
    }
}

<?xml version="1.0" encoding="UTF-8" ?>

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-5.1.xsd">

    <bean id="vehicle" class="org.example.Car"></bean>

</beans>

And Below is the error I got when running the application

Exception in thread "main" org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from class path resource [org/example/luxan.xml]; nested exception is java.io.FileNotFoundException: class path resource [org/example/luxan.xml] cannot be opened because it does not exist
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:345)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:305)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:188)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:224)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:195)
    at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:257)
    at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:128)
    at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:94)
    at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:130)
    at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:637)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:522)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:144)
    at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:85)
    at org.example.App.main(App.java:10)
Caused by: java.io.FileNotFoundException: class path resource [org/example/luxan.xml] cannot be opened because it does not exist
    at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:180)
    at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:331)
    ... 13 more

Answer 1

For your current location of luxan.xml in the above picture. you need to provide the whole classpath to the application context.

ApplicationContext context = new ClassPathXmlApplicationContext("main/java/org/example/luxan.xml");

if luxan.xml is located as the child of the src, we need not provide any path to the application context, just the name of XML is sufficient.

ApplicationContext context = new ClassPathXmlApplicationContext("luxan.xml");