Detail Spring Boot loading properties and yml configuration files

  • 2020-06-23 00:23:39
  • OfStack

1. Inject configuration after system startup


package com.example.config;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;

/**
 * @author: GrandKai
 * @create: 2016-09-01 11:24
 */
@Configuration
@PropertySource(ignoreResourceNotFound = true, value = {"classpath:/config/email.properties","classpath:/config/email.yml"}, name = "email")
public class Config {}

You need to register the configuration with ApplicationContext


AnnotationConfigEmbeddedWebApplicationContext context = (AnnotationConfigEmbeddedWebApplicationContext) app.run(" parameter 1");
context.register(Config.class);

Take the value in the following way


Environment env = context.getEnvironment();
System.out.println(env.getProperty("address"));

The email. yml file configuration is as follows:


server: 
 address: 127.0.0.1

2. Inject into the program from the command line


public class Main {
  public static void main(String... args) {
    //initialize the command line parsing stuff
    OptionParser parser = new OptionParser();
    parser.accepts("greeting").withRequiredArg();
    OptionSet options = parser.parse(args);

    //create the actual Spring PropertySource
    PropertySource<?> ps = new JOptCommandLinePropertySource(options);

    //setup the Spring context
    AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
    ctx.getEnvironment().getPropertySources().addLast(ps); 
    //register the property source with the environment

    ctx.register(Greeter.class);
    ctx.refresh();
    Greeter greeter = ctx.getBean(Greeter.class);
    greeter.sayGreeting();
  }
}

@Component
class Greeter {
  @Inject private Environment env;


  //the following would also work
  //@Value("${greeting}")
  //private String greeting;    

  /**
   * Print out the 'greeting' property if it exists, and otherwise, "Welcome!".
   */
  public void sayGreeting() {
    System.out.println(env.getProperty("greeting", "Welcome!"));
  }
}




public static void main(String [] args) {
  SimpleCommandLinePropertySource ps = new SimpleCommandLinePropertySource(args);
  @SuppressWarnings("resource")
  AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
  ctx.getEnvironment().getPropertySources().addFirst(ps);
  ctx.register(ApplicationConfig.class);
  ctx.refresh();
}


@Configuration
@EnableScheduling
@ComponentScan("com.mycompany.package")
@PropertySource(
    value = {"classpath:/application.properties", "file:${config.location}"},
    ignoreResourceNotFound = true
  )
class ApplicationConfig {

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

@Component
class MyComponent {

  @Value("${my.property.data}")
  private String myPropertyData;


  @Scheduled(fixedDelayString = "${schedule.delay.period}")
  public void run() {
     :
  }
}


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