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!
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.
In Spring XML, I can define a bean that instantiates a class annotated with #Configuration. When I do, that bean is post-processed. Any methods inside that class with #Bean are also added to the container. How do I perform a similar post-processing in JavaConfig?
Here's the XML version:
<bean id="test" class="com.so.Test">
<property name="prop" value="set before instantiating #Beans defined in Test"/>
</bean>
The associated Test class:
#Configuration
class Test {
private String prop;
void setProp(final String prop) {
this.prop = prop;
}
#Bean
NeedThisBean needThisBeanToo() {
return new NeedThisBean(prop);
}
}
If I use Spring XML Config, both test and needThisBeanToo are available in the container. needThisBeanToo is added via a BeanPostProcessor, though I can't recall which one. If I use JavaConfig, only test is available in the container. How do I make needThisBeanToo available to the container? #Import would work, except that prop being set is required for needThisBeanToo to be initialized correctly.
The part that makes all of this complicated is that Test is vended from a library I'm consuming. I don't control Test, nor can I change it. If I drive it from JavaConfig, it would look like this:
#Configuration
class MyConfiguration
{
#Bean
Test test() {
Test test = new Test();
test.setProp("needed to init `needThisBeanToo` and others");
return test;
}
}
The JavaConfig example does not instantiate needThisBeanToo despite it being defined in Test. I need to get needThisBeanToo defined, preferably without doing it myself, since I don't want to copy code I don't own. Delegation isn't attractive, since there are a number of subsequent annotations/scopes defined on needThisBeanToo (and others defined inside Test).
Your problem is is that you're ignoring the #Configuration annotation completely. Why is that?
When code reaches this line Test test = new Test(); it just doesn't do anything with #Configuration. Why? Because annotation is not something that a constructor is aware of. Annotation only marks some meta-data for the class. When spring loads classes it searches for annotations, when you call a constructor of a class, you don't. So the #Configuration is just ignored because you instantiate Test with new Test() and not through spring.
What you need to do is to import Test as a spring bean. Either via XML as you showed in your question OR using #Import. You problem with prop is that the setter isn't called because that's just not the way to do it. What you need to be doing is either do something like that:
#Configuration
class Test {
private String prop = "set before instantiating #Beans defined in Test";
#Bean
NeedThisBean needThisBeanToo() {
return new NeedThisBean(prop);
}
}
Or to create a property in spring (this is a different subject) and inject the value:
#Configuration
class Test {
#Autowired
#Value("${some.property.to.inject}") // You can also use SPeL syntax with #{... expression ...}
private String prop;
#Bean
NeedThisBean needThisBeanToo() {
return new NeedThisBean(prop);
}
}
You can also create a bean of type String and inject it as follows:
#Configuration
class Test {
#Autowired
#Qualifer("nameOfBeanToInject")
private String prop;
#Bean
NeedThisBean needThisBeanToo() {
return new NeedThisBean(prop);
}
}
In the last case you can define your original MyConfiguration with this bean:
#Configuration
#Import(Test.class)
class MyConfiguration
{
#Bean(name = "nameOfBeanToInject")
String test() {
return "needed to init `needThisBeanToo` and others";
}
}
In any case you have to import Test either using #Import or as a normal XML bean. It won't work by calling the constructor explicitly.
Here's a way to handle vended #Configuration classes that require some properties to be set prior to creating their #Beans:
Vended #Configuration class:
#Configuration
class Test {
private String property;
public setProperty(final String property) {
this.property = property;
}
#Bean
PropertyUser propertyUser() {
return new PropertyUser(property);
}
#Bean
SomeBean someBean() {
// other instantiation logic
return new SomeBeanImpl();
}
}
Here's the consuming #Configuration class:
#Configuration
class MyConfig {
#Bean
static String myProperty() {
// Create myProperty
}
/**
* Extending Test allows Spring JavaConfig to create
* the beans provided by Test. Declaring
* Test as a #Bean does not provide the #Beans defined
* within it.
*/
#Configuration
static class ModifiedTest extends Test {
ModifiedTest() {
this.setProperty(myProperty());
}
#Override
#Bean
SomeBean someBean() {
return new SomeBeanCustomImpl(this.propertyUser());
}
}
I wonder if there is a way to get #Required working when doing the configuration by annotations. I turned my configuration up-and-down and back again but nothing seems to work for me. I'm using Spring 3.1
My basic configuration looks like this:
#Configuration
public class SpringConfig {
#Bean
public MailSender mailSender() {
MailSender MailSender = new MailSender();
// mailSender.setBean(dlMailSender);
return mailSender;
}
#Bean
public MyBean myBean() {
MyBean myBean = new MyBean();
// setting som props
return myBean;
}
}
MailSender is here:
#Configurable
public class MailSender {
private MyBean myBean;
#Required
public void setMyBean(MyBean myBean) {
this.myBean = myBean;
}
}
I'm testing it with this junit:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = { SpringConfig.class }, loader = AnnotationConfigContextLoader.class)
public class MailSenderTest {
#Test
public void test_main_beans_exists() {
// when then given
}
}
Thanks for any help
Short answer - this is not even theoretically possible.
When using XML-based, bean definitions with their dependencies are completely managed by application context. Spring is able to check, what is being set and what is not being set.
When using annotation-based configuration, you are setting the dependencies yourself. There is no way how Spring can even know what you are doing with the bean before returning it from the factory method.
If you want to check whether the bean is correctly initialized, use InitializingBean or #PostConstruct and implement self-checking method. Spring is doing this regularly in its own beans.
I have a Spring 3.1 #Configuration that needs a property foo to build a bean. The property is defined in defaults.properties but may be overridden by the property in overrides.properties if the application has an active override Spring profile.
Without the override, the code would look like this, and work...
#Configuration
#PropertySource("classpath:defaults.properties")
public class MyConfiguration {
#Autowired
private Environment environment;
#Bean
public Bean bean() {
...
// this.environment.getRequiredProperty("foo");
...
}
}
I would like a #PropertySource for classpath:overrides.properties contingent on #Profile("overrides"). Does anyone have any ideas on how this could be achieved? Some options I've considered are a duplicate #Configuration, but that would violate DRY, or programmatic manipulation of the ConfigurableEnvironment, but I'm not sure where the environment.getPropertySources.addFirst() call would go.
Placing the following in an XML configuration works if I inject the property directly with #Value, but not when I use Environment and the getRequiredProperty() method.
<context:property-placeholder ignore-unresolvable="true" location="classpath:defaults.properties"/>
<beans profile="overrides">
<context:property-placeholder ignore-unresolvable="true" order="0"
location="classpath:overrides.properties"/>
</beans>
Update
If you're trying to do this now, check out Spring Boot's YAML support, particularly the 'Using YAML instead of Properties' section. The profile support there would make this question moot, but there isn't #PropertySource support yet.
Add the overriding #PropertySource in a static inner class. Unfortunately, you must specify all property sources together which means creating a "default" profile as the alternative to "override".
#Configuration
public class MyConfiguration
{
#Configuration
#Profile("default")
#PropertySource("classpath:defaults.properties")
static class Defaults
{ }
#Configuration
#Profile("override")
#PropertySource({"classpath:defaults.properties", "classpath:overrides.properties"})
static class Overrides
{
// nothing needed here if you are only overriding property values
}
#Autowired
private Environment environment;
#Bean
public Bean bean() {
...
// this.environment.getRequiredProperty("foo");
...
}
}
I suggest, defining two files, where the second is optional with the profile as suffix:
#Configuration
#PropertySources({
#PropertySource("classpath:/myconfig.properties"),
#PropertySource(value = "classpath:/myconfig-${spring.profiles.active}.properties", ignoreResourceNotFound = true)
})
public class MyConfigurationFile {
#Value("${my.prop1}")
private String prop1;
#Value("${my.prop2}")
private String prop2;
}
You can do:
<context:property-placeholder location="classpath:${spring.profiles.active}.properties" />
Edit: if you need something more advanced, you can register your PropertySources on application startup.
web.xml
<context-param>
<param-name>contextInitializerClasses</param-name>
<param-value>com.xxx.core.spring.properties.PropertySourcesApplicationContextInitializer</param-value>
</context-param>
file you create:
public class PropertySourcesApplicationContextInitializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
private static final Logger LOGGER = LoggerFactory.getLogger(PropertySourcesApplicationContextInitializer.class);
#Override
public void initialize(ConfigurableApplicationContext applicationContext) {
LOGGER.info("Adding some additional property sources");
String[] profiles = applicationContext.getEnvironment().getActiveProfiles()
// ... Add property sources according to selected spring profile
// (note there already are some property sources registered, system properties etc)
applicationContext.getEnvironment().getPropertySources().addLast(myPropertySource);
}
}
Once you've done it you just need to add in your context:
<context:property-placeholder/>
I can't really answer to your question about multiple profiles but I guess you activate them on such an initializer, and you could register the appropriate PropertySource items during profile activations.
I can't think of any other way than one you have suggested Emerson, which is to define this bean in a separate #Configuration file with an #Profile annotation:
#Configuration
#Profile("override")
#PropertySource("classpath:override.properties")
public class OverriddenConfig {
#Autowired
private Environment environment;
#Bean
public Bean bean() {
//if..
}
}
In case you need to support multiple profiles you could do something like this:
#Configuration
public class Config {
#Configuration
#Profile("default")
#PropertySource("classpath:application.properties")
static class DefaultProperties {
}
#Configuration
#Profile("!default")
#PropertySource({"classpath:application.properties", "classpath:application-${spring.profiles.active}.properties"})
static class NonDefaultProperties {
}
}
That way you don't need to define a static configuration class for each profile.
Thanks David Harkness for putting me into the right direction.
Note: This answer provides an alternate solution to using properties files with #PropertySource. I went this route because it was too cumbersome trying to work with multiple properties files that may each have overrides while avoiding repetitive code.
Create a POJO interface for each related set of properties to define their names and types.
public interface DataSourceProperties
{
String driverClassName();
String url();
String user();
String password();
}
Implement to return the default values.
public class DefaultDataSourceProperties implements DataSourceProperties
{
public String driverClassName() { return "com.mysql.jdbc.Driver"; }
...
}
Subclass for each profile (e.g. development, production) and override any values that differ from the default. This requires a set of mutually-exclusive profiles, but you can easily add "default" as the alternative to "overrides".
#Profile("production")
#Configuration
public class ProductionDataSourceProperties extends DefaultDataSourceProperties
{
// nothing to override as defaults are for production
}
#Profile("development")
#Configuration
public class DevelopmentDataSourceProperties extends DefaultDataSourceProperties
{
public String user() { return "dev"; }
public String password() { return "dev"; }
}
Finally, autowire the properties configurations into the other configurations that need them. The advantage here is that you don't repeat any #Bean creation code.
#Configuration
public class DataSourceConfig
{
#Autowired
private DataSourceProperties properties;
#Bean
public DataSource dataSource() {
BoneCPDataSource source = new BoneCPDataSource();
source.setJdbcUrl(properties.url());
...
return source;
}
}
I am still not convinced I'll stick with this over manually configuring properties files based on the active profiles in a servlet context initializer. My thought was that doing manual configuration would not be as amenable to unit testing, but I'm not so sure now. I really prefer reading properties files to a list of property accessors.
All mentioned here solutions are a bit awkward, work only with one profile preset, and they won't work with more/other profiles. Currently a Spring team refuses to introduce this feature. But here's the working workaround I've found:
package com.example;
public class MyPropertySourceFactory implements PropertySourceFactory, SpringApplicationRunListener {
public static final Logger logger = LoggerFactory.getLogger(MyPropertySourceFactory.class);
#NonNull private static String[] activeProfiles = new String[0];
// this constructor is used for PropertySourceFactory
public MyPropertySourceFactory() {
}
// this constructor is used for SpringApplicationRunListener
public MyPropertySourceFactory(SpringApplication app, String[] params) {
}
#Override
public void environmentPrepared(ConfigurableBootstrapContext bootstrapContext, ConfigurableEnvironment environment) {
activeProfiles = environment.getActiveProfiles();
}
#Override
public PropertySource<?> createPropertySource(String name, EncodedResource encodedResource) throws IOException {
logger.info("Loading: {} with profiles: {}", encodedResource.toString(), activeProfiles);
// here you know all profiles and have the source Resource with main
// properties, just try to load other resoures in the same path with different
// profile names and return them as a CompositePropertySource
}
}
To make it working you have to have src/main/resources/META-INF/spring.factories with the following content:
org.springframework.boot.SpringApplicationRunListener=com.example.MyPropertySourceFactory
Now you can put your custom properties file somewhere and load it with #PropertySources:
#Configuration
#PropertySource(value = "classpath:lib.yml", factory = MyPropertySourceFactory.class)
public class PropertyLoader {
}