How to read data from java properties file using Spring Boot

Question

I have a spring boot application and I want to read some variable from my application.properties file. In fact below codes do that. But I think there is a good method for this alternative.

Properties prop = new Properties(); InputStream input = null;  try {     input = new FileInputStream("config.properties");     prop.load(input);     gMapReportUrl = prop.getProperty("gMapReportUrl"); } catch (IOException ex) {     ex.printStackTrace(); } finally {     ... } 

Answer 1

You can use @PropertySource to externalize your configuration to a properties file. There is number of way to do get properties:

1. Assign the property values to fields by using @Value with PropertySourcesPlaceholderConfigurer to resolve ${} in @Value:

@Configuration @PropertySource("file:config.properties") public class ApplicationConfiguration {      @Value("${gMapReportUrl}")     private String gMapReportUrl;      @Bean     public static PropertySourcesPlaceholderConfigurer propertyConfigInDev() {         return new PropertySourcesPlaceholderConfigurer();     }  } 

2. Get the property values by using Environment:

@Configuration @PropertySource("file:config.properties") public class ApplicationConfiguration {      @Autowired     private Environment env;      public void foo() {         env.getProperty("gMapReportUrl");     }  } 

Hope this can help