JavaConfig – SpringExpL

Suppose I have a POJO called Address, I’d like to load external resource data and replace the address line1 and line2 value.

public class Address {
	
	private String addressline1;
	
	private String addressline2;

	// getter and setter
	
}

address.properties

address.line1= 123 Abc Condominium, 
address.line2= Street 123456

Partition Application Context

Now i partition the application context into AppConfig and InfraConfig, and I’ll show 2 approach on how to do it.

InfraConfig.java

@Configuration
@PropertySource("classpath:address.properties")
public class InfraConfig {

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

First Approach – AppConfig.java

@Configuration
@Import(InfraConfig.class)
public class AppConfig {
	
	@Value("${address.line1}") private String addressline1;
	@Value("${address.line2}") private String addressline2;
	
	@Bean
	public Address address() {
		Address address = new Address();
		address.setAddressline1(addressline1);
		address.setAddressline2(addressline2);
		return address;
	}
}
	

Create a client code to run.

public static void main(String[] args) {
		
   ApplicationContext ctx = new AnnotationConfigApplicationContext(AppConfig.class);
		
   Address address = ctx.getBean(Address.class);
   System.out.println(address.getAddressline1());
   System.out.println(address.getAddressline2());

}

Alternative – Use Environment

Second Approach – AppConfig.java

@Configuration
@Import(InfraConfig.class)
public class AppConfig {
	
	@Autowired
	private Environment env;
	
	@Bean
	public Address address() {
		Address address = new Address();
		address.setAddressline1(env.getProperty("address.line1"));
		address.setAddressline2(env.getProperty("address.line2"));
		return address; 
	}
	
}