我想通过使用@ConfigurationProperties注释将我的application.properties自动绑定到一个类中.首先,我尝试使用@Value注释,并能够将属性值注入类变量.但是,@ ConfigurationProperties没有将属性注入值.
我的application.properties:
spring.jpa.show-sql=false my.url=my_url my.name=muatik
application.java
package com.muatik; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.context.ApplicationContext; @SpringBootApplication public class Application { public static void main(String[] args) { final ApplicationContext ctx = SpringApplication.run(Application.class, args); final ConfigBinder confs = ctx.getBean(ConfigBinder.class); System.out.println(confs.getUrl()); System.out.println(confs.getName()); } }
ConfigBinder.java
package com.muatik; import org.springframework.beans.factory.annotation.Value; import org.springframework.boot.context.properties.ConfigurationProperties; import org.springframework.stereotype.Component; @Component @ConfigurationProperties(prefix="my") public class ConfigBinder { @Value("${my.name}") private String name; private String url; // expected to be filled automatically public String getUrl() { return this.url; } public String getName() { return this.name; } }
输出:
... 2017-01-18 15:19:29.720 INFO 4153 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http) 2017-01-18 15:19:29.724 INFO 4153 --- [ main] com.muatik.Application : Started Application in 4.212 seconds (JVM running for 4.937) null muatik
这个实现有什么问题?
编辑和解决方案:可能的重复:Spring Boot @ConfigurationProperties不从环境中检索属性
我发现我错过了ConfigBinder中的setter.添加后,它现在可以使用了.
您需要从属性类中删除@Component并添加setter,因为标准bean属性绑定用于@ConfigurationProperties
:
@ConfigurationProperties(prefix="my") public class ConfigBinder { private String name; private String url; // expected to be filled automatically public String getUrl() { return this.url; } public String getName() { return this.name; } public void setName(String name) { this.name = name; } public void setUrl(String url) { this.url = url; } }
并将@EnableConfigurationProperties添加到您的主类:
@SpringBootApplication @EnableConfigurationProperties(ConfigBinder.class) public class Application { public static void main(String[] args) { final ApplicationContext ctx = SpringApplication.run(Application.class, args); final ConfigBinder confs = ctx.getBean(ConfigBinder.class); System.out.println(confs.getUrl()); System.out.println(confs.getName()); } }
主要问题是你没有设置者.当你把setter放到ConfigBuilder工作正常.ConfigBuilder必须是这样的
@Component @ConfigurationProperties(prefix="my") public class ConfigBinder { private String name; private String url; // Getters and Setters !!! }