Printing all properties set via Spring PropertyPlaceholderConfigurer

Question

I’d like to print the consolidated list of properties set in our application on startup. What is the best way to do this?

Thanks

Answer 1

Here is a concrete example of printing all properties :

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
import org.springframework.web.context.support.StandardServletEnvironment;

public class PropertiesLoaderConfigurer
    extends PropertySourcesPlaceholderConfigurer {

    private static final String ENVIRONMENT_PROPERTIES = "environmentProperties";

    @Override
    public void postProcessBeanFactory(
        final ConfigurableListableBeanFactory beanFactory)
        throws BeansException {

        super.postProcessBeanFactory(beanFactory);

        final StandardServletEnvironment propertySources =
            (StandardServletEnvironment) super.getAppliedPropertySources().get(ENVIRONMENT_PROPERTIES).getSource();

        propertySources.getPropertySources().forEach(propertySource -> {
            if (propertySource.getSource() instanceof Map) {
                // it will print systemProperties, systemEnvironment, application.properties and other overrides of
                // application.properties
                System.out.println("#######" + propertySource.getName() + "#######");

                final Map<String, String> properties = mapValueAsString((Map<String, Object>) propertySource.getSource());
                System.out.println(properties);
            }
        });
    }

    private Map<String, String> mapValueAsString(
        final Map<String, Object> map) {

        return map.entrySet().stream()
            .collect(Collectors.toMap(entry -> entry.getKey(), entry -> toString(entry.getValue())));
    }

    private String toString(
        final Object object) {

        return Optional.ofNullable(object).map(value -> value.toString()).orElse(null);
    }
}

Answer 2

This is my implementation:

public class CustomPropertySourcesPlaceholderConfigurer extends PropertySourcesPlaceholderConfigurer implements InitializingBean{

    public void afterPropertiesSet(){
        try{
            Properties loadedProperties = this.mergeProperties();
            for(Entry<Object, Object> singleProperty : loadedProperties.entrySet()){
                logger.info("LoadedProperty: "+singleProperty.getKey()+"="+singleProperty.getValue());
            }
        }catch(Exception ex){
            ex.printStackTrace();
        }
    }
}

Answer 3

Use a custom PropertyPlaceholderConfigurer implementation that overrides the resolve... methods and logs the placeholder name. You may also need/want to override the convert... methods, but resolve... should handle it.