I have multiple library classes in my project which need to be injected into a service class. This is the error statement for IntegrationFactory class:
Consider defining a bean of type 'com.ignitionone.service.programmanager.integration.IntegrationFactory' in your configuration.
This error is coming on almost every injection where this library class is injected.
I have already added the Library package in #ComponentScan, but, as it is read-only file, I can not annotate the library class. I came to know from some answer here that Spring can not inject classes which it does not manage. This library is not built on spring.
I have tried to create a #Bean method which returns the IntegrationFactory(class in question) in the class where #Inject is used, but this too does not seem to work.
How can this be done, preferably without creating a stub/copy class?
This is EngagementServiceImpl class snippet:
#Inject
public EngagementServiceImpl(EngagementRepository engagementRepository,
#Lazy IntegrationFactory integrationFactory, TokenRepository tokenRepository,
EngagementPartnerRepository engagementPartnerRepository, MetricsService metricsService) {
this.engagementRepository = engagementRepository;
this.integrationFactory = integrationFactory;
this.tokenRepository = tokenRepository;
this.engagementPartnerRepository = engagementPartnerRepository;
this.metricsService = metricsService;
}
This is injection part:
#Autowired
private EngagementService engagementService;
This is ConfigClass:
#Configuration
public class ConfigClass {
#Bean
public IntegrationFactory getIntegrationFactory(){
Map<String, Object> globalConfig = new HashMap<>();
return new IntegrationFactory(globalConfig);
}
#Bean
#Primary
public EntityDataStore getEntityDataStore(){
EntityModel entityModel = Models.ENTITY;
return new EntityDataStore(this.dataSource(), entityModel );
}
#ConfigurationProperties(prefix = "datasource.postgres")
#Bean
#Primary
public DataSource dataSource() {
return DataSourceBuilder
.create()
.build();
}
}
You need to add your bean definitions in a configuration class.
#Configuration
public class ServiceConfig {
#Bean
public IntegrationFactory getIntegrationFactory(){
// return an IntegrationFactory instance
}
}
Then you have to make sure your #Configuration class gets detected by Spring, either by having it within your scanned path or by manually importing it via #Import from somewhere withing you scanned path. An example of #Import, considering you are using Spring Boot.
#Import(ServiceConfig.class)
#SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
Hope this helps!
Your Bean IntegrationFactory can't be found, as it is not annotated with any Spring stereotype and therefore not recognized by the component scan.
As you have multiple options to provide an instance of your class to the application context, read the Spring documentation (which also includes samples) to find out which one fits you the most:
https://docs.spring.io/spring/docs/5.1.0.RELEASE/spring-framework-reference/core.html#beans-java-basic-concepts
One Option would be to create a factory which provides an instance of your class to the application context, like it is stated in the documentation:
#Configuration
public class AppConfig {
#Bean
public IntegrationFactory myIntegrationFactory() {
return new IntegrationFactory();
}
}
Do not forget to add the Configuration to the application context.
Related
I am learning concepts of Spring & I came across #Bean & #Component annotations. I want to know what will happen in below scenario:
#Configuration
class ConfigClass {
#Bean
public ComponentClass ComponentClass() {
return new ComponentClass(someDependency1, someDependency2, someDependency3);
}
}
#Component
class ComponentClass{
private SomeDependency1 sd1;
private SomeDependency2 sd2;
private SomeDependency3 sd3;
public ComponentClass(SomeDependency1 sd1, SomeDependency2 sd2, SomeDependency3 sd3) {
/* initialize here */
}
}
I have declared ComponentClass as #Component which means it is a spring bean now. But I have also defined a #Bean for it in config class separately.
Which of these beans will be actually used as by default Spring is singleton?
What happens when I remove #Component?
Spring will notice a mistake and throw NoUniqueBeanDefinitionException during application startup.
If you remove #Component annotation it will work as expected, #Bean will be used for initialization.
I'm using Spring Boot with a thrift server, and I have two #Configuration class with two bean generation method, and the code is as following:
#Configuration
public class EagleBeanCreator {
#Bean(destroyMethod = "destroy")
public EagleRestClient build() {
EagleRestClient client = new EagleRestClient();
// some set values code
return client;
}
}
And another one:
#Configuration
public class EagleServiceBuilder {
#Autowired
private EagleRestClient eagleProxy;
#Bean
public EagleService eagleService() {
EagleService service = new EagleService();
System.out.println(eagleProxy);
service.setEagleProxy(eagleProxy);
return service;
}
}
But when I run spring-boot:run, it print out null for "System.out.println(eagleProxy);"
Why?
=========================UPDATE=============================
I know setter injection or constructor injection works.
You may want to try this out.
#Configuration
public class EagleServiceBuilder {
#Bean
public EagleService eagleService(EagleRestClient eagleProxy) {
EagleService service = new EagleService();
System.out.println(eagleProxy);
service.setEagleProxy(eagleProxy);
return service;
}
}
My guess is that the way you currently implement doesn't indicate a dependency between the EagleService and EagleRestClient. So your current implementation leads to random initialization order between the two beans. The modified version tells Spring "Hey, my EagleService depends on EagleRestClient. Please initialize EagleRestClient before EagleService.
Because the order to load EagleBeanCreator and EagleServiceBuilder is not definite. You can use #Order or #ConditionalOnClass to make sure EagleBeanCreator initialize first.
Because the #Configuration bean are initialized in the same phase of bean lifecycle. I don't remember them clearly but something like:
Configurations -> Components -> Services
With the beans in the same phase, if they depend on each other, you should declare the load order by some #Conditional or #Order
Add #DependsOn("eagleRestClient") annotation on the definition of EagleService.
#DependsOn("eagleRestClient")
#Bean
public EagleService eagleService() {
EagleService service = new
EagleService();
System.out.println(eagleProxy);
service.setEagleProxy(eagleProxy);
return service;
}
Spring will then first create rest client then the eagle service.
First, you need to get the spring container through ApplicationContextAware try
ApplicationContext.getBean(EagleRestClient.class)
I have a component Login that depends on ValidatorService. ValidatorService is being injected/autowired in the Login constructor. ValidationServiceImpl is provided by an external API, so I can't just annotate it as #Service.
#Component
class Login {
#Autowire
public Login (ValidatorService validator) {
}
}
#SpringBootApplication
public class Starter {
public static void main(String[] args)
{
SpringApplication.run(Starter.class, args);
}
}
I'm looking for a way to register ValidatorService as a bean before #Components get scanned. Is there a way to get ApplicationContext instance before starting the application?
SpringBoot 2.0.4.RELEASE
UPDATE
I need to pass a validationId that I'll get from main(args) to this external API.
public static void main(String[] args) {
String validationId = args[0];
ValidatorService service = ExternalValidationAPI.getValidationServiceImp(validationId);
}
You should be able to declare it as a bean as such in one of your configuration classes:
#Bean
public ValidatorService validatorService(){
return new ValidatorServiceImpl();
}
This will then autowire in the ValidatorService implementation class at the point it is needed. This method needs to go in an #Configuration class (your Starter class is one).
There's a good example of how to do this here.
I believe you can solve your problem with the help of the #Configurable annotation.
Annotate your Login class with #Configurable instead of #Componenet, and when the ValidatorService object becomes available, you can initiate the Login object with it.
You need to define a ValidationService bean :
#Configuration
public class ValidationServiceConfig {
#Bean
public ValidationService validationService(#Value("${validationId}") String validationId) {
return new ValidationServiceImpl(validationId);
}
}
and run the program this way : java -jar program.jar --validationId=xxx
I solved my problem creating a Configuration class and declaring a Bean to handle the instantiation of the external service that will be injected later (as some people have suggested). In order to retrieve the program arguments I autowired DefaultApplicationArguments to retrieve program arguments with getSourceArgs():
#Configuration
public class ValidatorConfig {
#Autowired
DefaultApplicationArguments applicationArguments;
#Bean
public ValidatorService validatorService()
{
String validationId = applicationArguments.getSourceArgs()[0];
return ExternalValidationAPI.getValidationServiceImp(validationId);
}
My project has a dependency on another one, and imports beans from it (using #ImportResource("foo.xml")).
foo.xml defines two datasources (datasource1 and datasource2), I would like to make datasource1 a primary (so all auto-configurations of Spring Boot will work).
Is it possible? I found out that there is a DefaultListableBeanFactory that has determinePrimaryCandidate method.
So the idea is to create my own ListableBeanFactory, that would extend the DefaultListableBeanFactory, but how to force Spring Boot to use my implementation?
Or maybe there is another, easier way to mark a given bean as primary (without changing the configuration where it is defined).
You can create a configuration in your project, which builds a new data source annotated as #Primary bean. This new data source will be the datasource1, which will be injected by spring to the new data source factory method. Here you have the working example.
The config:
#SpringBootApplication
public class BeanSpringExampleApplication
{
#Bean(name = "dataSource1")
public FakeDataSource dataSource1()
{
return new FakeDataSource("dataSource1");
}
#Bean(name = "dataSource2")
public FakeDataSource dataSource2()
{
return new FakeDataSource("dataSource2");
}
#Bean
#Primary
public FakeDataSource primaryDataSource(
#Qualifier("dataSource1") FakeDataSource dataSource1)
{
return dataSource1;
}
}
Here you see three beans (using FakeDataSource class), which simulate your situation. The primaryDataSource bean factory method simply returns the dataSource1 (it's just a mere data source selector).
The FakeDataSource is just a placeholder, to make example runnable:
public class FakeDataSource
{
private final String fakeProperty;
public FakeDataSource(String id)
{
fakeProperty = id;
}
/**
* #return the fakeProperty
*/
public String getFakeProperty()
{
return fakeProperty;
}
}
Finally, a test which proves everything is working:
#RunWith(SpringRunner.class)
#SpringBootTest
public class BeanSpringExampleApplicationTests
{
#Autowired
private FakeDataSource fakeDataSource;
#Test
public void should_AutowirePrimaryDataSource() throws Exception
{
assertEquals("dataSource1", fakeDataSource.getFakeProperty());
}
}
I recently started working at a place that uses Java configuration for Spring as opposed to XML and so far I'm loving it.
My question is the following:
If we have a #Configuration annotated class A that imports another #Configuration annotated class B, what is the proper, type-safe way for a bean defined in A to depend on a bean defined in B.
Here's an example I saw in a blog (https://blog.codecentric.de/en/2012/07/spring-dependency-injection-styles-why-i-love-java-based-configuration/):
#Configuration
public class PartnerConfig {
#Bean
public PartnerService partnerService() {
return new PartnerServiceImpl();
}
}
#Configuration
#Import(PartnerConfig.class)
public class CashingConfig {
#Autowired
private PartnerConfig partnerConfig;
#Bean
public CashingService cashingService() {
return new CashingServiceImpl(partnerConfig.partnerService());
}
}
As a second part to my question, if I was to do the above, would Spring interpret as a bean dependency? That is, when I do
partnerConfig.partnerService()
in the example above, am I getting Spring to fetch me the partnerService bean, or am I just calling a regular java method and creating a new instance of the PartherService (which is NOT what I want, since the bean should be a singleton) ?
EDIT:
It has been suggested to use a #Qualifier. Would this work?
#Configuration
public class PartnerConfig {
#Bean
#MyCustomQualifier
public PartnerService partnerService() {
return new PartnerServiceImpl();
}
}
#Configuration
#Import(PartnerConfig.class)
public class CashingConfig {
#Bean
public CashingService cashingService(#MyCustomQualifier PartnerService partnerService) {
return new CashingServiceImpl(partnerService);
}
}
I recommend giving the docs a read: http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/context/annotation/Bean.html
Refer to the section:
#Bean Methods in #Configuration Classes
This sums it up very well.
Typically, #Bean methods are declared within #Configuration classes. In this case, bean methods may reference other #Bean methods in the same class by calling them directly. This ensures that references between beans are strongly typed and navigable.
Also take a look at: http://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/context/annotation/Configuration.html
Section:
Composing #Configuration classes
Just add the dependency as an argument to the #Bean annotated method and remove the autowiring of the configuration.
#Configuration
#Import(PartnerConfig.class)
public class CashingConfig {
#Bean
public CashingService cashingService(PartnerService partnerService) {
return new CashingServiceImpl(partnerService);
}
}
or simply autowire the PartnerService instead of the configuration.
#Configuration
#Import(PartnerConfig.class)
public class CashingConfig {
#Autowire
private PartnerService partnerService;
#Bean
public CashingService cashingService() {
return new CashingServiceImpl(partnerService);
}
}