Spring ${} is not working in @Value

A simple Spring @PropertySource example to read a properties file.

db.driver=oracle.jdbc.driver.OracleDriver

@Configuration
@PropertySource("classpath:db.properties")
public class AppConfig {
	@Value("${db.driver}")
	private String driver;

But the property placeholder ${} is unable to resolve in @Value, if print out the driver variable, it will display string ${db.driver} directly, instead of “oracle.jdbc.driver.OracleDriver”.

Solution

To resolve ${} in Spring @Value, you need to declare a STATIC PropertySourcesPlaceholderConfigurer bean manually. For example :

import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
@Configuration
@PropertySource("classpath:db.properties")
public class AppConfig {
	@Value("${db.driver}")
	private String driver;
	@Bean
	public static PropertySourcesPlaceholderConfigurer propertyConfigInDev() {
		return new PropertySourcesPlaceholderConfigurer();

For XML configuration, Spring will help you to register PropertySourcesPlaceholderConfigurer automatically.

<util:properties location="classpath:db.properties"/>