使用java config在Spring应用程序的Web项目外部单独存储属性

Question

I want to hold properties in Tomcat server. I want initialize some bean for development and some for production. What is the best solution?

I tried to use Condition interface, but I receive NullPointerException. It seams that I didn't receive value from my property. What I'm doing wrong?

I place my property file in /home/user/apache-tomcat-home-dir/conf/my.properties and add

 <Environment name="my_config" value="file:///${catalina.home}/conf/my.properties" type="java.net.URI"/>

to /home/user/apache-tomcat-home-dir/conf/context.xml .

In my.properties only one property:

profiler.default=dev

And that's how I use my property in project:

public class ProductionCondition implements Condition {

    @Value("${profiler.default}")
    private String prodProfiler;

    @Override
    public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
        return prodProfiler.equals("production");
    }
}

public class DevCondition implements Condition {

    @Value("${profiler.default}")
    private String coreProfiler;

    @Override
    public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
//        return coreProfiler.equals("dev");
        return context.getEnvironment().getProperty("profiler.default").contains("dev");
    }
}

Than I should to configure PropertySourcesPlaceholderConfigurer to initialize properties from file:

@Configuration(value = "propertiesConfiguration")
@PropertySource(value="file:${catalina.home}/conf/my.properties")
public class PropertiesConfiguration {

    @Bean
    public static PropertySourcesPlaceholderConfigurer placeholderConfigurer() throws MalformedURLException {
        PropertySourcesPlaceholderConfigurer configurer = new PropertySourcesPlaceholderConfigurer();
//        configurer.setLocation(new FileSystemResource(propertyFile));
        return configurer;
    }
}

What is correct form: ${catalina.home} or ${catalina/home} or how to specify relative path to my property file?

In configuration class I initialize Conditional beans and specify, that this config class depends on PropertiesConfiguration.

@Configuration
@Import({PropertiesConfiguration.class})
@DependsOn("propertiesConfiguration")
public class ApplicationConfig {

    @Bean
    @Conditional(ProductionCondition.class)
    public FooInterface productionVendorCore() {
        return new ProductionImpl();
    }

    @Bean
    @Conditional(DevCondition.class)
    public FooInterface devVendorCore() {
        return new DevImpl();
    }
//....
}

But anyway I receive NPE in ProductionCondition:

return prodProfiler.equals("production");

Appreciate any help!

Answer 1

Instead of trying to invent your own wheel, try to use the ones provided already. Use profiles instead.

In your tomcat simply add SPRING_PROFILES_ACTIVE property to jndi with the value you want production or dev . Or you can set it as a environment or jvm property.

<Environment name="SPRING_PROFILES_ACTIVE" value="production" type="java.lang.String"/>

Then annotate your bean definities with @Profile and enable them for certain profiles.

public class ApplicationConfig {

    @Bean
    @Profile("production")
    public FooInterface productionVendorCore() {
        return new ProductionImpl();
    }

    @Bean
    @Profile("dev")
    public FooInterface devVendorCore() {
        return new DevImpl();
    }
    //....
}

This should only load the beans in the enabled profile. Without any additional work from your side.