I am writing a custom spring starter, in which I need to register a list of beans of same type based on the property defined in the application.properties
i have following properties in application.properties
mybean.names = mybean1, mybean2
mybean1.foo = foo1
mybean2.foo = foo2
mybean1.bar = bar1
mybean2.bar = bar2
Current implementation of autoconfiguration class is below
#Configuration
#ConditionalOnClass(MyBeanFactory.class)
public class MyBeanAutoConfiguration {
#Autowire
Environemnt evn;
#Bean(name = {"mybean1"})
public MyBean getBean() {
String[] names = StringUtils.commaDelimitedListToStringArray(evn.getProperty("mybean.names"));
MyBean mybean = new Mybean(evn.getProperty(names[0] + ".foo"),
evn.getProperty(names[0] + ".bar"));
return myBean;
}
}
And i want to simply autowire with qualifer my bean in spring boot application like below
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class MyApplication {
#Autowired
#Qualifer("mybean1")
MyBean mybean;
public static void main(String[] args) {
SpringApplication.run(VaultApplication.class, args);
}
How can i change my autoconfigure class to create multiple beans with different names defined in the properties file(in this case how can I create bean mybean2) so that i can use simply autowire with qualifier ?
I am not sure that i understood you question but if you want to have several bean with different name so best way is writing multiple #Bean method in your configuration class with different name, so you can autowire each one of them by #Qualifer
Related
I'm trying to get Spring Boot dependency injection to allow me to do the following:
interface MyBean
#Component
class MyBeanA : MyBean
#Component
class MyBeanB : MyBean
#Component
class MyBeanConsumer(myBean: MyBean)
Here, Spring complains that there are multiple beans of type MyBean. I would like it to create two instances of MyBeanConsumer. One with MyBeanA and one with MyBeanB. I need to do this for a number of beans, so I'm trying to avoid boilerplate configuration classes like this:
#Configuration
class MyBeanConfiguration {
#Bean
fun consumers(myBeans: List<MyBean>) = myBeans.map { MyBeanConsumer(it) }
}
Is this possible in Spring?
you can use the Qualifier annotation and specify the name of the bean requested.
you can visit this
Spring #Autowired and #Qualifier
If everywhere in your program you want to inject them as List of beans you can go with this approach.
#Configuration public MyConfigurationClass {
#Bean
#Qualifier("mylist")
public List<MyType> configure() {
//create your dynamical list here
}
}
But if you want to use them as individual bean somewhere in your program and also you want to inject all of them as a List somewhere else you can do that this way:
#Configuration
public class AppConfig implements BeanFactoryPostProcessor {
#Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
for (int i = 0; i < 3; i++) {
System.out.println("register my bean: " + i);
beanFactory.registerSingleton("bean-" + i, new MyBean("MyBean-" + i));
}
}
Read the following answer for further detail:
How to create multiple beans of same type according to configuration in Spring?
I want to configure in my #Configuration class bean which is already created by other library's autoconfiguration. I just need to change some fields in that class after it's being initialized.
But I can't find a proper way how to provide code block in #Configuration class and not using #Bean annotation. Is there an ideomatic way to do so in spring?
One way to do this:
#Configuration
class TestConfig {
#Autowired
private SomeBean someBean;
#PostConstruct
private void initSomeBean() {
// someBean.setProperty("qwe");
}
}
#PostConstruct annotation defines init-method, which is getting called after SomeBean is autowired. In this method you can adjust your bean
Do you want to import one Config in AnotherConfig on? It can be done via annotation placed on AnotherConfig:
import org.springframework.context.annotation.Import;
...
#Import(value = {Config.class})
public class AnotherConfig ... {}
I have the following classes:
#ComponentScan
public class CDPlayerConfig {
#Autowired
private static CompactDisc cd;
public static void main(String[] args) {
ApplicationContext context = new AnnotationConfigApplicationContext(CDPlayerConfig.class);
CompactDisc cd = context.getBean(CompactDisc.class);
System.out.println(cd);
}
}
public interface CompactDisc {
void play();
}
#Component
public class SgtPeppers implements CompactDisc {
public void play() {
System.out.println("play song....");
}
}
When I run the class CDPlayerConfig, the program runs successfully. However, if I remove the ComponentScan annotation to CompactDisc interface or SgtPeppers I get the following error:
Exception in thread "main"
org.springframework.beans.factory.NoSuchBeanDefinitionException: No
qualifying bean of type 'CompactDisc' available
I think that ComponentScan annotation marks the package where Spring looks for beans. CDPlayerConfig, CompactDisc and SgtPeppers are all placed in the same package, so allegedly moving ComponentScan annotation from one class to another should not make a difference.
If so, why do I get an error?
For #ComponentScan to work you have to "tell" spring where to search, or it must find it with help of other, already loaded, #ComponentScan annotated class (your class must be then annotated also with #Component, #Configuration etc. so it could be found).
In your case, you register application context in the first line of main method - you have specified there to load CDPlayerConfig.class which is #ComponentScan annotated so now spring can automatically find other beans in the package:
ApplicationContext context =
new AnnotationConfigApplicationContext(CDPlayerConfig.class);
If you want to move #ComponentScan to another class, you have to change class registered in AnnotationConfigApplicationContext to some #ComponentScan annotated class:
SgtPeppers:
#Component
#ComponentScan
public class SgtPeppers implements CompactDisc {
(...)
Main in CDPlayerConfig:
ApplicationContext context =
new AnnotationConfigApplicationContext(SgtPeppers.class);
Note you should register context from concrete classes (not interfaces).
Also, above sample would work even without #ComponentScan annotation on SgtPeppers, but then beans defined in other classes from the package wouldn't be found.
In my springboot application I am performing Integration tests using the following class
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = AccountLoadApplication.class,
loader = SpringApplicationContextLoader.class)
#WebIntegrationTest(randomPort = true)
public class LoaderTest {
AccountLoadApplication.class is a spring boot main class and the actual application has a bean defined like below:
#Bean
public ResourceLoader recapMvsFileResourceLoader() {
return new RemoteFileResourceLoader(remoteHostProperties(), new SFTPRemoteFileService());
}
Also I have a Test Configuration class like below
#Configuration
public class AtddTestConfig {
#Bean
public ResourceLoader mvsFileResourceLoader() {
ResourceLoader recapMvsFileResourceLoader =
new RemoteFileResourceLoader(remoteHostProperties(), new FakeSFTPRemoteFileService());
return recapMvsFileResourceLoader;
}
My Idea is that I want to override the bean created in the main application using the new bean defined in the test Configuration file.
But during integration tests the main application bean is considered instead of the bean defined in the test application context?
Is There any other way to achieve what i am trying to achieve ?
Additional Info:
Here are the beans defined in my Application configuration class
#Bean
public RemoteFileService remoteFileService() {
return new SFTPRemoteFileService();
}
#Bean
public ResourceLoader recapMvsFileResourceLoader() {
return new RemoteFileResourceLoader(remoteHostProperties(), remoteFileService());
}
Here are the beans defined in my Test configuration class
#Bean
#Profile("local")
#Primary
public RemoteFileService remoteFileService() {
return new FakeSFTPRemoteFileService();
}
Still the production bean is only created instead of this primary bean.
Use #Profile annotation to enable testing bean only in test context
Use #Primary annotation on testing bean, so that spring would use test bean instead of production one.
Here is my Github repository with working example using this mechanism.
Maybe when you add your test configuration as parameter for #ContextConfiguration it resolves problem, e.g.
#ContextConfiguration(classes = {AccountLoadApplication.class, AtddTestConfig.class},
loader = SpringApplicationContextLoader.class)
Along with the other changes suggested by #luboskrnac, you have to declare #ActiveProfiles; otherwise, your local profile is simply ignored.
#RunWith(SpringJUnit4ClassRunner.class)
#ActiveProfiles("local")
#SpringApplicationConfiguration(AccountLoadApplication.class)
#WebIntegrationTest(randomPort = true)
public class LoaderTest { /* ... */ }
Note that the above assumes that your AtddTestConfig class gets picked up via component scanning by your AccountLoadApplication class.
#Autowired
Environment env;
#Value("${jdbcConnectionString}")
private String jdbcConnectionString;
The above works automagically in certain classes, however is null in similar classes in same package and with same annotations #Configuration/#Component.
I am trying to find out the proper approach to understand what spring does when while configuring various artifacts.
I am able to run stuff every now and then but any good resource to understand the magic is well appreciated.
PS. I am only interested in java-config based approach now.
Working :
package a.b.c;
#Configuration
public class AppConfig {
#Autowired
Environment env;
package a.b.d;
#Configuration
#EnableBatchProcessing
public class JobConfiguration {
#Autowired
private Environment env;
package a.b.L;
public class BatchJobListener implements Ordered, JobExecutionListener {
#Autowired
public Environment env;
Not working inside
package a.b.u
Tried to annotate classes with #Component/#Configuration
In order to autowire a bean, you need first to defined it in a Context.
#Configuration
public class ConfigOne {
#Bean
public String myBean(){
return "my bean";
}
}
The bean that you want to inject and the bean where the bean will be injected need to be in the same context. You can do it with:
JavaConfigApplicationContext context =
new JavaConfigApplicationContext(ConfigOne.class, ConfigTwo.class);
Or you can use #import to import one configuration class into another.
#Configuration
#Import(ConfigTwo.class)
public class ConfigOne {
UPDATE
What I meant was that probably you're not making the configuration in the ringht way. So all your beans where you're injecting the enviroment are not in the same context.
However, if you have configured well everything, it's possible that some classes are loading before enviroment. In this case you can use EnvironmentAware
#Configuration
#PropertySource("classpath:myProperties.properties")
public class MyConfiguration implements EnvironmentAware {
private Environment environment;
#Override
public void setEnvironment(final Environment environment) {
this.environment = environment;
}
public void myMethod() {
final String myPropertyValue = environment.getProperty("myProperty");
// ...
}
}
In your main class where you are initializing the spring boot application, do you have similar configuration:
#Configuration
#SpringBootApplication
#EnableAutoConfiguration
#ComponentScan("a.b") //Note that this scans the components where you have configured spring container backed objects
#PropertySource({
"classpath:someProperty1.properties",
"classpath:someProperty2.properties"
})
public class Main{
public static void main(String[] args) {
SpringApplication.run(Main.class, args);
}
}
What this basically does is, it tells spring that this is a configuration class, and indicates this configuration class that it also triggers auto-configuration and component scanning (scan only these specific packages (a.b) and check if there are any annotations present for automatic bean detection, like: #Component, #Service, #Controller, #Repository). On detecting any class which have these stereotypes spring would create object(s) depending on the configuration. On creating these objects one may have autowired some objects or one could refer to some property defined in properties file. The config #PropertySource does this.
The package declaration in #ComponentScan should be the base package.