I have one interface MyInterface, and 2 implementation beans: FirstImpl & SeconImpl. I want to switch between using these 2 implementations while program is running without restarting it, by only changing a property in application.properties file, e.g: interface.bean.default=FirstImpl change to interface.bean.default=SecondImpl.
Anyone knows how to do that with Spring boot?
You could try to use #ConditionalOnProperty:
#Configuration
public class MyInterfaceConfiguration {
#Bean
#ConditionalOnProperty(value = "my.interfacte.impl", havingValue="firstImpl")
public MyInterface firstImpl(){
return new FirstImpl();
}
#Bean
#ConditionalOnProperty(value = "my.interfacte.impl", havingValue="secondImpl")
public MyInterface secondImpl(){
return new SecondImpl();
}
}
and when you update your property in application.properties with actuator/refresh to:
my.interfacte.impl=firstImpl
you will have your FirstImpl instance. When you have:
my.interfacte.impl=secondImpl
you will have your SecondImpl.
#Hasan, your update only works if I customize it a little bit as below:
#Configuration
#RefreshScope
public class MyInterfaceConfiguration {
#Value("${my.interfacte.impl}")
String impl;
#Bean
#RefreshScope
public MyInterface getBean(){
if ("firstImpl".equals(impl)) {
return new FirstImpl();
} else if ("secondImpl".equals(impl)) {
return new SecondImpl();
}
return null;
}
}
I have to use 2 #RefreshScope at class level and bean creation method level!
Related
I have a #ConfigurationProperties class that is no longer binding to a YML property source that gets resolved via Spring Cloud Config after upgrading to Hoxton.SR7. This code works fine using Hoxton.SR4 with the latest Spring Boot 2.2.9.RELEASE. Now, my properties are not bound and I'm receiving NPEs when I try to reference them. Following is a snapshot of my code:
#Configuration
public class MyConfiguration {
#Bean
public MyPropertiesBean myPropertiesBean() {
return new MyPropertiesBean();
}
}
#ConfigurationProperties(prefix = "com.acme.properties")
#Validated
public class MyPropertiesBean {
...
}
In src/main/resources/META-INF/spring.factories:
org.springframework.boot.autoconfigure.EnableAutoConfiguration=com.acme.MyConfiguration
Any ideas why my #ConfigurationProperties class doesn't bind after upgrading Spring Cloud to Hoxton.SR7?
You're mixing two ways of binding properties: class and method.
Using a method and #Bean annotation:
#Configuration
public class MyConfiguration {
#Bean
#ConfigurationProperties(prefix = "com.acme.properties")
#Validated
public MyPropertiesBean myPropertiesBean() {
return new MyPropertiesBean();
}
}
This will create MyPropertiesBean and store it inside the application context for you to inject.
Class level bean declaration also creates a bean for you:
#Configuration
#ConfigurationProperties(prefix = "com.acme.properties")
#Validated
public class MyPropertiesBean {
...
}
This will also store a bean.
Although, you should be getting a runtime error when you try to inject MyPropertiesBean as now in your case there's two beans of the same type and Spring cannot resolve with only the type.
I'm a Spring rookie and trying to benefit from the advantages of the easy 'profile' handling of Spring. I already worked through this tutorial: https://spring.io/blog/2011/02/14/spring-3-1-m1-introducing-profile and now I'd like to adapt that concept to an easy example.
I've got two profiles: dev and prod. I imagine a #Configuration class for each profile where I can instantiate different beans (implementing a common interface respectively) depending on the set profile.
My currently used classes look like this:
StatusController.java
#RestController
#RequestMapping("/status")
public class StatusController {
private final EnvironmentAwareBean environmentBean;
#Autowired
public StatusController(EnvironmentAwareBean environmentBean) {
this.environmentBean = environmentBean;
}
#RequestMapping(method = RequestMethod.GET)
Status getStatus() {
Status status = new Status();
status.setExtra("environmentBean=" + environmentBean.getString());
return status;
}
}
EnvironmentAwareBean.java
public interface EnvironmentAwareBean {
String getString();
}
EnvironmentAwareBean.java
#Service
public class DevBean implements EnvironmentAwareBean {
#Override
public String getString() {
return "development";
}
}
EnvironmentAwareBean.java
#Service
public class ProdBean implements EnvironmentAwareBean {
#Override
public String getString() {
return "production";
}
}
DevConfig.java
#Configuration
#Profile("dev")
public class DevConfig {
#Bean
public EnvironmentAwareBean getDevBean() {
return new DevBean();
}
}
ProdConfig.java
#Configuration
#Profile("prod")
public class ProdConfig {
#Bean
public EnvironmentAwareBean getProdBean() {
return new ProdBean();
}
}
Running the example throws this exception during startup (SPRING_PROFILES_DEFAULT is set to dev):
(...) UnsatisfiedDependencyException: (...) nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [EnvironmentAwareBean] is defined: expected single matching bean but found 3: prodBean,devBean,getDevBean
Is my approach far from a recommended configuration? In my opinion it would make more sense to annotate each Configuration with the #Profile annotation instead of doing it for each and every bean and possibly forgetting some variants when new classes are added later on.
Your implementations of EnvironmentAwareBean are all annotated with #Service.
This means they will all be picked up by component scanning and hence you get more than one matching bean. Do they need to be annotated with #Service?
Annotating each #Configuration with the #Profile annotation is fine. Another way as an educational exercise would be to not use #Profile and instead annotate the #Bean or Config classes with your own implementation of #Conditional.
I'm having an issue with the order resolution of Spring Java/XML configuration. It seems that the #Value annotations are not being resolved ahead of #Bean factory methods being invoked, specifically when loading properties from external XML configuration.
This is a condensed version of what I'm doing:
#Configuration
#ImportResource({"classpath:configurable-context.xml"})
public class SecurityConfig {
#Value("#{myProps['my.custom.key']}")
private String someValue = null;
#Bean
public SomeObject someObject() {
return new SomeObject(someValue); // Fails because someValue == null
}
}
and this is configurable-context.xml :
...
<util:map id="myProps">
<entry key="my.custom.key" value="myVal"/>
</util:map>
...
The issue is that the someObject(...) factory method is invoked ahead of the #Value annotation being evaluated for someValue, so this is null at the time.
Any thoughts on how I can force resolution of the someValue variable ahead of the factory method being invoked?
Update
As inspired by response from #Ekem, this code worked for me using XML sourced properties:
#Configuration
#ImportResource({"classpath:configurable-context.xml"})
public class SecurityConfig {
#Resource(name = "myProps")
private Properties myProps;
#Bean
public SomeObject someObject() {
return new SomeObject(myProps.getProperty("my.custom.key")); // Now works :-)
}
}
Change your configuration as follows so that myProps bean is initialized first
#Configuration
#ImportResource({"classpath:configurable-context.xml"})
public class SecurityConfig {
#Value("#{myProps['my.custom.key']}")
private String someValue = null;
#Bean
#DependOn("myProps")
public SomeObject someObject() {
return new SomeObject(someValue);
}
}
Alternatively to make your configuration clean use of the environment abstraction as follows
#Configuration
#PropertySource("classpath:application.properties")
public class SecurityConfig {
#Autowired
private private Environment env;
#Bean
public SomeObject someObject() {
return new SomeObject(env.getProperty("my.custom.key"));
}
}
Then add an application.properties file to the root of your classpath with an entry my.custom.key=myVal
This will eliminate the need for an xml application context just to define a hardcoded property
I'm trying to implement Togglz & Spring using #Configuration beans rather than XML. I'm not sure how to configure the return type of the Configuration bean. For example:
#Configuration
public class SystemClockConfig {
#Bean
public SystemClock plainSystemClock() {
return new PlainSystemClock();
}
#Bean
public SystemClock awesomeSystemClock() {
return new AwesomeSystemClock();
}
#Bean
public FeatureProxyFactoryBean systemClock() {
FeatureProxyFactoryBean proxyFactoryBean = new FeatureProxyFactoryBean();
proxyFactoryBean.setActive(awesomeSystemClock());
proxyFactoryBean.setInactive(plainSystemClock());
proxyFactoryBean.setFeature(Features.AWESOME_SYSTEM_CLOCK.name());
proxyFactoryBean.setProxyType(SystemClock.class);
return proxyFactoryBean;
}
}
The systemClock method returns a FeatureProxyFactoryBean but the clients of this bean require a SystemClock. Of course, the compiler freaks over this.
I imagine it just works when XML config is used. How should I approach it when using a configuration bean?
I'm not an expert for the Java Config configuration style of Spring, but I guess your systemClock() method should return a proxy created with the FeatureProxyFactoryBean. Something like this:
#Bean
public SystemClock systemClock() {
FeatureProxyFactoryBean proxyFactoryBean = new FeatureProxyFactoryBean();
proxyFactoryBean.setActive(awesomeSystemClock());
proxyFactoryBean.setInactive(plainSystemClock());
proxyFactoryBean.setFeature(Features.AWESOME_SYSTEM_CLOCK.name());
proxyFactoryBean.setProxyType(SystemClock.class);
return (SystemClock) proxyFactoryBean.getObject();
}
But I'm not sure if this is the common way to use FactoryBeans with Spring Java Config.
I'm trying to create a MainConfig that imports another Config by using an #Bean method instead of #Import like this :
#Configuration
public class MainConfig {
#Bean
public Service service() {
return new Service(infrastructureConfig().database());
}
#Bean
public OtherService otherService() {
return new OtherService(infrastructureConfig().database());
}
#Bean
public InfrastructureConfig intrastructureConfig() {
return new InfrastructureConfig();
}
}
#Configuration
public class InfrastructureConfig {
#Bean
public Database database() {
return new Database();
}
...
}
When using this technique, the Database is created twice because Spring doesn't seem to consider the #Configuration annotation on InfrastructureConfig. When using #Import, it works fine.
I don't want to use #Import because I want to mock my InfrastructureConfig like this :
#Configuration
public class TestConfig extends MainConfig {
#Override
public InfrastructureConfig infrastructureConfig() {
return mock(InfrastructureConfig.class);
}
}
Am I missing something or it is not supported ?
Thanks
When I first tried out Spring Java configuration I think I made the same assumption and was surprised when it didn't work.
I'm not sure this is the neatest way of solving this but I have used the following approach successfully.
To include that #Configuration class you can add this annotation to your MainConfig:
#ComponentScan(basePackages = "org.foo", includeFilters = {#Filter(filterType = ANNOTATION, value = CONFIGURATION)}, excludeFilters = {#Filter(filterType = ASSIGNABLE_TYPE, value = MainConfig)})
Since #Configuration classes are also candidates for component scanning this allows you to scan for all classes annotated with #Configuration. Since you're putting this annotation on MainConfig you need to exclude that with the ASSIGNABLE_TYPE filter since you'll get a circular reference.
I opened a Spring ticket SpringSource JIRA and they said that it is a known limitation and it is working as designed.