Issue with @Value and application.properties since moving to Spring Boot 1.1.4.RELEASE

Question

I am having an issue since I moved to version 1.1.4.RELEASE of Spring Boot.

My variables that are annotated with @Value are presently not being populated with values despite them being present in the application.properties. Prior to this I was using Spring Boot @ version 1.0.2, and that was working fine.

It all started since the upgrade, and I made no code change.

SampleApplication.java

package org.sample;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;

@Configuration
@ComponentScan
@EnableAutoConfiguration
@PropertySource(value = "classpath:application.properties")
public class SampleApplication {

private static Logger logger = LoggerFactory
        .getLogger(TaskManagerApplication.class);

@Value("${org.sample.sampleProperty}")
private static String sampleProperty;

public static void main(String[] args) {

    SpringApplication.run(SampleApplication.class, args);
    System.out.print("SampleApplication started: " + sampleProperty);

}

@Bean
public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {

    return new PropertySourcesPlaceholderConfigurer();

}
}

application.properties

spring.datasource.url: jdbc:mysql://127.0.0.1:3306/mydb
spring.datasource.username: root
spring.datasource.password: root
spring.datasource.driverClassName: com.mysql.jdbc.Driver
spring.jpa.show-sql: true

#Disable the ddl-auto:create once tables have been created
#spring.jpa.hibernate.ddl-auto: create

org.sample.sampleProperty=This is a sample property

photos.upload.dir=C:/temp/UserPhotos/

# Server port
server.port=8081

I have tried to add a PropertySourcesPlaceholderConfigurer bean and even PropertySourcesPlaceholderConfigurer but still the issue persists.

Anyone experienced this ? Or is there a new way to load the properties file ?

Please note that my db connection and server port are being read properly since my application can connect to db and I have to access it through the specified port. sampleProperty variable remains null though.

Answer 1

1. @Value is not meant to work on static fields
2. Properties from application.properties are available automatically without specifying @PropertySource for it.
3. Instead of printing out property in main() method, you should do it after bean is constructed, for example by using @PostConstruct

Fully working example:

package demo;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;

import javax.annotation.PostConstruct;

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class Application {

    @Value("${org.sample.sampleProperty}")
    private String sampleProperty;

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @PostConstruct
    public void postConstruct() {
        System.out.print("SampleApplication started: " + sampleProperty);
    }
}