如何在 Spring Boot 配置类中属性文件值

Question

如何在 Config 类中使用 application.properties 文件

application.properties

datasource.username=test

配置类

 @Configuration
 @EnableTransactionManagement
 @EnableJpaRepositories(
    entityManagerFactoryRef = "abcFactory", 
    transactionManagerRef = "abcmanager",
    basePackages = { "com.emp.repository" }) 

    public class EmpConfig {
    
        @Value("${datasource.username}")
        String username;
        
        @Bean(name = "empDataSource")      
        public DataSource empDataSource(String url, String userName, String pwd) {        
         DriverManagerDataSource dataSource = new DriverManagerDataSource();
         dataSource.setDriverClassName("XXX");
         dataSource.setUrl(url);
         dataSource.setUsername(userName);
         dataSource.setPassword(pwd);         
         return dataSource;        
 
        }
    
    
    }

如何将属性传递到用户名集字段。

Answer 1

取决于你如何初始化你的应用程序，但通常你会放类似

@EnableAutoConfiguration
@PropertySource("classpath:application.properties")
@ComponentScan
@SpringBootApplication
@EnableTransactionManagement

确保您的配置中有其中之一

@Bean
public static PropertySourcesPlaceholderConfigurer propertyPlaceholderConfigurer() {
    return new PropertySourcesPlaceholderConfigurer();
}

然后你可以访问这样的值

@Value("${datasource.username}")
@NotNull //optional
String username;