Spring註解解析之@ImportResource
一、ImportResource
1.1 定義包和類
首先定義一個不會被ComponentScan
掃描到的包outpackage
,如下:
在該包內創建一個類:
package outpackage; import org.springframework.stereotype.Service; @Service public class HelloService1 { public void method1() { System.out.println("class:HelloService1__method:method1"); } }
1.2 定義配置文件
在資源目錄添加配置文件applicationContext.xml
:
<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" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"> <!-- 開啟註解模式 --> <context:annotation-config/> <!-- 基於註解自動註冊spring bean --> <context:component-scan base-package="outpackage"/> </beans>
1.3 定義Java Config類
在啟動類平級目錄或者是子目錄添加java config類保證能夠被springboot掃描到
,引入xml配置,如下:
package dongshi.daddy; import org.springframework.context.annotation.Configuration; import org.springframework.context.annotation.ImportResource; @Configuration @ImportResource({"classpath:applicationContext.xml"}) public class OuterPackageConfiguration { }
1.4 測試代碼
@SpringBootApplication public class HelloWorldMainApplication { public static void main(String[] args) throws URISyntaxException, IOException { ConfigurableApplicationContext run = SpringApplication.run(HelloWorldMainApplication.class, args); // 獲取通過配置文件定義而被掃描到的類 HelloService1 bean = run.getBean(HelloService1.class); System.out.println(bean); } }
二、運行
2021-05-19 17:52:52.896 INFO 16232 — [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8083 (http) with context path ”
…snip…
outpackage.HelloService1@1929425f
為瞭證明確實是xml配置文件在起作用,而不是springboot自己掃描註冊,修改配置類,註釋掉@ImportResource({"classpath:applicationContext.xml"})
,如下:
package dongshi.daddy; import org.springframework.context.annotation.Configuration; @Configuration //@ImportResource({"classpath:applicationContext.xml"}) public class OuterPackageConfiguration { }
然後運行:
2021-05-19 18:01:10.522 INFO 18260 — [ main] dongshi.daddy.HelloWorldMainApplication : Started HelloWorldMainApplication in 0.944 seconds (JVM running for 1.355)
Exception in thread “main” org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type ‘outpackage.HelloService1’ available
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:351)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean(DefaultListableBeanFactory.java:342)
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1123)
at dongshi.daddy.HelloWorldMainApplication.main(HelloWorldMainApplication.java:16)
可以看到就找不到對應的bean瞭。
到此這篇關於Spring註解解析之@ImportResource的文章就介紹到這瞭,更多相關@ImportResource註解內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet!
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