How get working @Value or Environment in a class implementing the Condition/ConfigurationCondition interfaces

Question

I am working with only JavaConfig.

I have the following declaration:

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

it is mandatory for JavaConfig according with the following post: Spring 3.2 @value annotation with pure java configuration does not work, but Environment.getProperty works

The following code works perfect (many @Values by testing purposes):

@Configuration
public class ActiveMQServerConfiguration {

    @Value("${localhost.address}")
    private String localHost;

    @Value("${remotehost.address}")
    private String remoteHost;

    @Value("${localhost.port}")
    private Integer localPort;

    @Value("${remotehost.port}")
    private Integer remotePort;

    @Bean(name="connectionFactory")
    @Conditional(LocalHostStatusCondition.class)
    public ActiveMQConnectionFactory localConnectionFactory(
            @Value("${localhost.protocol}") String protocol,
            @Value("${localhost.address}") String host,
            @Value("${localhost.port}") String port ){

        System.out.println("protocol: "+protocol);
        System.out.println("host: "+host);
        System.out.println("port: "+port);

        System.out.println("localHost: "+localHost);
        System.out.println("localPort: "+localPort);
        System.out.println("remoteHost: "+remoteHost);
        System.out.println("remotePort: "+remotePort);

I can see in the console/terminal

Alpha

protocol: tcp
host: 127.0.0.1
port: 61616
localHost: 127.0.0.1
localPort: 61616
remoteHost: 192.168.1.34
remotePort: 61616

But the following does not works how expected:

public class LocalHostStatusCondition implements Condition {

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

    @Value("${localhost.address}")
    private String localHost;

    @Value("${remotehost.address}")
    private String remoteHost;

    @Value("${localhost.port}")
    private Integer localPort;

    @Value("${remotehost.port}")
    private Integer remotePort;

    @Autowired
    private Environment environment;

    @Override
    public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
        logger.info("LocalHostStatusCondition...");

        System.out.println("localHost: "+localHost);
        System.out.println("localPort: "+localPort);
        System.out.println("remoteHost: "+remoteHost);
        System.out.println("remotePort: "+remotePort);
        System.out.println("Env..." + environment.getProperty("localhost.address", String.class) );

Practically the same and even working with Environment

The output is:

Beta

localHost: null
localPort: null
remoteHost: null
remotePort: null
[WARNING] 
java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.codehaus.mojo.exec.ExecJavaMojo$1.run(ExecJavaMojo.java:293)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at com.manuel.jordan.infrastructure.support.LocalHostStatusCondition.matches(LocalHostStatusCondition.java:42)

According with the Condition API:

Conditions must follow the same restrictions as BeanFactoryPostProcessor and take care to never interact with bean instances. For more fine-grained control of conditions that interact with @Configuration beans consider the ConfigurationCondition interface.

About ConfigurationCondition I have read this When to use Spring @ConfigurationCondition vs. @Condition? too

I have edited to the following:

public class LocalHostStatusCondition implements ConfigurationCondition {

…

    @Override
    public ConfigurationPhase getConfigurationPhase() {
        return ConfigurationPhase.PARSE_CONFIGURATION;
    }

If I use:

• ConfigurationPhase.REGISTER_BEAN I get the same output how Beta
• ConfigurationPhase.PARSE_CONFIGURATION; I get no errors but...

but the console/terminal does not show nothing about the sentences working, I mean, System.out are not printing (I don't understand about this weird behaviour).

How I can resolve this?

I need have working @Value or Environment, it with the purpose to let know the application if should connect to a local or remote ActiveMQ server.

And yes, I have read the following: How do I delay evaluation of a Spring @Conditional configuration annotation? seems there is no solution…

Thank You

Answer 1

You have

@Conditional(LocalHostStatusCondition.class)

Spring takes the Class type you've specified and instantiates it to use its matches method. It doesn't consider the instance as a bean, it doesn't perform autowiring on it, nor any @Value processing. The latter are true for BeanFactoryPostProcessor as well.

You can retrieve the Environment from the ConditionContext if you want to. The alternative is to load the properties yourself.