Spring proxy beans from Interface - spring

What is the correct way to create proxy beans by interfaces?
public class JdbiRepositoryAnnotationBeanPostProcessorTest {
private DBI dbi = mock(DBI.class);
#org.junit.Test
public void testIncompleteBeanDefinition() {
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
ctx.register(JdbiRepositoryAnnotationBeanPostProcessor.class);
ctx.register(MyConfig.class);
ctx.refresh();
ITest bean = ctx.getBean(ITest.class);
assertNotNull(bean);
}
#JdbiRepository
public static interface ITest {
}
#Configuration
#ComponentScan(basePackageClasses = {ITest.class},
includeFilters = {#ComponentScan.Filter(type = FilterType.ANNOTATION, value = JdbiRepository.class)})
public static class MyConfig {
}
}
I have tried bean post processor but It did not help me.
Edit:
I wanted to use component scanning by including annotation filter but it did not help me too.
Edit:
I want to create instances by another library which is creating proxy beans as this:
TestInterface proxy = factory.onDemand(TestInterface.class);
Edit:
I have extended InstantiationAwareBeanPostProcessorAdapter for JdbiRepositoryAnnotationBeanPostProcessor.
I have been just logging currently. But I can not see my interfaces as a bean.
Please note that I have also changed my test code above.
public class JdbiRepositoryAnnotationBeanPostProcessor implements BeanPostProcessor, BeanFactoryAware {
private ConfigurableListableBeanFactory beanFactory;
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
return bean;
}
#Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
return bean;
}
#Override
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
if(!(beanFactory instanceof ConfigurableListableBeanFactory)) {
throw new IllegalArgumentException("AutowiredAnnotationBeanPostProcessor requires a ConfigurableListableBeanFactory");
}
this.beanFactory = (ConfigurableListableBeanFactory) beanFactory;
// this.dbiMap = this.beanFactory.getBeansOfType(DBI.class);
}
}

The problem was related to ComponentScanning not PostBeanProcessor. ComponentScan is scanning only concrete classes that is why my processor did not work. I had to create a custom importer for interfaces.

Related

Injecting Spring Dependencies into ConstrantValidator

I'm using Bean Validation. I have a custom validator #MyValidator that needs to look up a value with an injected Spring managed DAO object. How can I get access to this? Spring isn't injecting the DAO into my "MyValidator" object.
#Component
public class CodeListValidator implements ConstraintValidator<CodeList, String> {
#Autowired
private ICodeListCommonService codeListCommonService;
private CodeListEnum codeListID;
#Override
public void initialize(CodeList constraintAnnotation) {
this.codeListID = constraintAnnotation.value();
}
#Override
public boolean isValid(String value, ConstraintValidatorContext context) {
return codeListCommonService.doesCodeEntityExistForCodeList(codeListID.getDbCodeListId(), value, ProviderConstants.CODE_LIST_STATUS_ACTIVE);
}
}
The "codeListCommonService" is null. This is because Spring isn't creating the class - but how can I get this to work with Spring AoP?
The use of this validator looks like this:
ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
Validator validator = factory.getValidator();
MyObject validateMe = new MyObject();
Set<ConstraintViolation<MyObject>> constraintViolations = validator.validate(validateMe);
For MyObject:
public class MyObject {
#Size(max = 1)
#CodeList(CodeListEnum.CARTYPE)
public String carType;
}
So when the validator runs, it processes the annotations... I just need to get a service injected into the CodeListValidator I made to it can do a DB lookup to verify the value against the DB list of "valid car type values".
EDIT: The solution:
Played around with the idea of making a Spring aware factory- too much integration with existing code.
The solution that seems the best (and it works here) is to make a Spring service that stores the ApplicationContext in a static method so "non-Spring managed" beans can get to them.
So a new service:
#Service
public class SpringApplicationContextService implements ISpringApplicationContextService, ApplicationContextAware {
private static ApplicationContext applicationContext;
#Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
this.applicationContext = applicationContext;
}
public static ApplicationContext getApplicationContext() {
return applicationContext;
}
}
And then any validator or non-Spring bean can get at the Spring beans via:
public class CodeListValidator implements ConstraintValidator<CodeList, String> {
#Autowired
private ICodeListCommonService codeListCommonService;
private CodeListEnum codeListID;
#Override
public void initialize(CodeList constraintAnnotation) {
this.codeListID = constraintAnnotation.value();
}
#Override
public boolean isValid(String value, ConstraintValidatorContext context) {
ICodeListCommonService codeListCommonService = SpringApplicationContextService.getApplicationContext().getBean(ICodeListCommonService.class);
return codeListCommonService.doesCodeEntityExistForCodeList(codeListID.getDbCodeListId(), value, ProviderConstants.CODE_LIST_STATUS_ACTIVE);
}
}
And, of course, the reason for all of this (which is used dozens of times in this app):
#CodeList(CodeListEnum.EMAIL_OPT_OUT_FLAG)
public String emailOptOutFlag;
#CodeList(CodeListEnum.CLEARING_HOUSE)
public String clearingHouse;
The minimum setup for #Autowired to work properly in ConstraintValidator implementation is to have this bean in a Spring #Configuration:
#Bean
public Validator defaultValidator() {
return new LocalValidatorFactoryBean();
}
This allows any beans, including ApplicationContext, to be injected directly into a ConstraintValidator:
#Constraint(validatedBy = DemoValidator.class)
public #interface DemoAnnotation {
// ...
Class<?> beanClass();
}
public class DemoValidator implements ConstraintValidator<DemoAnnotation, String> {
private final ApplicationContext applicationContext;
private Object bean;
#Autowired
public DemoValidator(ApplicationContext applicationContext) {
this.applicationContext = applicationContext;
}
#Override
public void initialize(DemoAnnotation constraint) {
Class<?> beanClass = constraint.beanClass();
bean = applicationContext.getBean(beanClass);
}
#Override
public boolean isValid(String obj, ConstraintValidatorContext context) {
return !obj.isEmpty();
}
}
Demo
For a really flexible validation solution I would recommend Jakub Jirutka's Bean Validator utilizing Spring Expression Language (SpEL) which allows things like:
public class Sample {
#SpELAssert("#myService.calculate(#this) > 42")
private int value;
}

Autowiring not working in springboot application

I am trying to create a Spring boot application with JFrame. I can see my beans in applicationContext but they are not getting autowired. I am unable to find the reason for this issue. Can someone help me with this?
Here is the code:
JavauiApplication - it is showing both userManager and userNameRepository is beans
#SpringBootApplication
public class JavauiApplication implements CommandLineRunner {
#Autowired
private ApplicationContext appContext;
public static void main(String[] args) {
new SpringApplicationBuilder(JavauiApplication.class).headless(false).run(args);
java.awt.EventQueue.invokeLater(() -> new InputNameForm().setVisible(true));
}
#Override
public void run(String... args) throws Exception {
String[] beans = appContext.getBeanDefinitionNames();
Arrays.sort(beans);
for (String bean : beans) {
System.out.println(bean);
}
}
}
InputNameForm.java -> userManager coming null
#Component
public class InputNameForm extends javax.swing.JFrame {
/**
* Creates new form InputNameForm
*/
public InputNameForm() {
initComponents();
}
#Autowired
UserManager userManager;
private void submitButtonActionPerformed(java.awt.event.ActionEvent evt) {
userManager.setName(firstName.getText(), lastName.getText());
}
/**
* #param args the command line arguments
*/
public static void main(String args[]) {
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(InputNameForm.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new InputNameForm().setVisible(true);
}
});
}
// Variables declaration - do not modify//GEN-BEGIN:variables
private javax.swing.JTextField firstName;
private javax.swing.JLabel firstNameLabel;
private javax.swing.JTextField lastName;
private javax.swing.JLabel lastNameLabel;
private javax.swing.JButton submitButton;
// End of variables declaration//GEN-END:variables
}
UserManager.java -> userNameRepository is coming null
#Component
public class UserManager {
#Autowired
UserNameRepository userNameRepository;
public void setName(String firstName, String lastName) {
userNameRepository.save(new UserName(firstName, lastName));
System.out.println(userNameRepository.findAllByFirstName(firstName));
}
}
It's a very common problem and it occurs because newcomers don't understand how the IoC container works.
Firstly, BeanDefinitionReader reads metadata about your beans from XML, Annotations(#Component, #Service etc), JavaConfig or Groovy script.
There are several BeanPostProcessor's which is responsible for reading all of these Spring annotation you're writing(#Autowired etc).
BeanFactory creates all BeanPostProcessor's then it creates all of your beans.
What happen if you create your bean with #Autowired dependencies via new operator? Nothing, because it isn't actually a bean. The object you created isn't related to IoC container. You may have the bean already in your ApplicationContext if you marked it with #Component(for example) but the object which was created via new operator wont be processed by Spring(annotations won't work).
Hope this helps.
PS: The lifecycle is simplified.
I had the same problem few days ago. What I undertood was that GUI builders like the one that comes with netbeans will automatically create components using new keyword. This means that those components won't be manage by spring. The code usually loks like this:
private void initComponents() {
jPanel1 = new javax.swing.JPanel(); //This component will not be managed by spring.
//...
}
You could use the following class provided here, to make it work.
#Component
public class BeanProvider {
private static ApplicationContext applicationContext;
// Autowires the specified object in the spring context
public static void autowire(Object object) {
applicationContext.getAutowireCapableBeanFactory().autowireBean(object);
}
#Autowired
private void setApplicationContext(ApplicationContext applicationContext) {
BeanProvider.applicationContext = applicationContext;
}
}
The top level SwingApp class:
#SpringBootApplication
public class SwingApp implements CommandLineRunner {
public static void main(String[] args) {
new SpringApplicationBuilder(SwingApp.class)
.headless(false).bannerMode(Banner.Mode.OFF).run(args);
}
#Override
public void run(String... args) throws Exception {
SwingUtilities.invokeLater(() -> {
MainFrame frame = new MainFrame();
frame.setVisible(true);
});
}
}
The MainFrame class:
public class MainFrame extends javax.swing.JFrame {
public MainFrame() {
initComponents();
}
private void initComponents() {
//Gui Builder generated code. Bean not managed by spring.
//Thus, autowired inside CustomPanel won't work if you rely on ComponentScan.
jPanel1 = new CustomJPanel();
//...
}
private CustomJPanel jPanel1;
}
The panel class where you want to autowire things:
//#Component //not needed since it wont work with gui generated code.
public class CustomJPanel extends javax.swing.JPanel{
#Autowired
private SomeRepository someRepository
public CustomJPanel(){
BeanProvider.autowire(this); //use someRepository somewhere after this line.
}
}
I have the same problem in a JavaFx project. Service and Component annotated classes were null in UI controllers even if it was shown in context that it was created. Below code worked for me
#Component
public class FxmlLoaderWithContext {
private final ApplicationContext context;
#Autowired
public FxmlLoaderWithContext(ApplicationContext context) {
this.context = context;
FXMLLoader fxmlloader = new FXMLLoader();
fxmlloader.setControllerFactory(context::getBean); //this row ensure services and components to be autowired
}
}
I think it returns null because you using command new to create object, such as new InputNameForm(). When creating object like that, the object isn't managed by Spring. That's why autowired not working.
The solution is registering your class as a bean.
You can use a class like in here.
#Component
public class BeanProvider {
private static ApplicationContext applicationContext;
public static void autowire(Object object) {
applicationContext.getAutowireCapableBeanFactory().autowireBean(object);
}
#Autowired
private void setApplicationContext(ApplicationContext applicationContext) {
BeanProvider.applicationContext = applicationContext;
}
}
And then, in your class InputNameForm constructor, call this:
class InputNameForm() {
BeanProvider.autowire(this);
...
}
And that's it. Spring will take care the rest.

#Before #PostConstruct Spring AOP ineterception

I'm trying to write an aspect that can intercept PostConstruct methods. I've looked at related questions on SO and others, and following them, this is what I have so far:
The Spring configuration
#Configuration
#EnableAspectJAutoProxy
#EnableLoadTimeWeaving
#...//other config annotations
public class WebConfiguration {
#Bean
public CommonAnnotationBeanPostProcessor commonAnnotationBeanPostProcessor() {
return new CommonAnnotationBeanPostProcessor();
}
... // etc
}
The annotation:
#Retention(RetentionPolicy.RUNTIME)
public #interface Secured {
Permission[] permissions() default {};
}
The bean
#Component
#Scope("request")
public class SomeWebBean {
#Secured(permissions = Permission.SOME_PERMISSION)
#PostConstruct
public void secure() {
... // some stuff
}
}
The aspect
#Component
#Aspect
public class SecuredAspect {
#Before("#annotation(secured)")
public void doAccessCheck(Secured secured) {
... // actually do the access check
}
}
If I call someWebBean.secure() from a page, then the aspect is invoked. However, it is not invoked on bean creation.
So as a note to future me - this absolutely cannot be done in this way using Spring AOP.
However, the same effect can be achieved by implementing a BeanPostProcessor as below:
public class SecureBeanPostProcessor implements BeanPostProcessor {
#Override
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
Secured secured = bean.getClass().getAnnotation(Secured.class);
if (secured != null) {
// do your security test here, throw an exception, return false, however you like
}
return bean;
}
#Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
return bean;
}
}
You can extend CommonAnnotationBeanPostProcessor and override postProcessBeforeInitialization(Object bean, String beanName)
Then register replace the original CommonAnnotationBeanPostProcessor with a BeanFactoryPostProcessor .
public class InitCommonAnnotationBeanPostProcessor extends CommonAnnotationBeanPostProcessor {
#Override
public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
return super.postProcessBeforeInitialization(bean, beanName);
}
}
public class InitBeanFactoryPostProcessor implements BeanFactoryPostProcessor {
#Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
BeanDefinitionRegistry registry = (BeanDefinitionRegistry) beanFactory;
RootBeanDefinition def = new RootBeanDefinition(InitCommonAnnotationBeanPostProcessor.class);
def.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
registry.registerBeanDefinition(AnnotationConfigUtils.COMMON_ANNOTATION_PROCESSOR_BEAN_NAME, def);
}
}
#Configuration
public class InitialisationMonitoringConfig {
public static final String BEAN_INIT_MONITOR = "BEAN_INIT_MONITOR";
#Bean
public static InitBeanFactoryPostProcessor initBeanFactoryPostProcessor() {
return new InitBeanFactoryPostProcessor();
}
}
This is ugly, but I had to do that to analyse startup times in dev environment.
Maybe it's enough to just declare InitCommonAnnotationBeanPostProcessor as a bean, I didn't tried.

Spring - Create bean based on Annotation field

UPDATE: I used a different approach for my problem.
Side-Question: I would like to know how spring does it with the exclude in SpringBootApplication
The SpringBootApplication:
#Target(ElementType.TYPE)
#Retention(RetentionPolicy.RUNTIME)
#Documented
#Inherited
#SpringBootConfiguration
#EnableAutoConfiguration
#ComponentScan(excludeFilters = #Filter(type = FilterType.CUSTOM, classes = TypeExcludeFilter.class))
public #interface SpringBootApplication {
So when the context is loaded, and the EnableAutoConfiguration is executed, the excludes are available.
Thats the same what i want.
At Bean-Creation i want to know if an Annotation has some field (for example boolean)
Old Question:
I have an Annotation:
#Target(ElementType.TYPE)
#Retention(RetentionPolicy.RUNTIME)
#Import(TaskSpringContext.class)
public #interface TaskTest
{
Class<? extends DatabaseService> db() default DatabaseService.class;
}
This Annotation is used at:
#TaskTest(db = DatabaseServiceExtended.class)
#SpringBootApplication()
public class TaskServer
{
public static void main(String[] args)
{
final ApplicationContext ctx = SpringApplication.run(TaskServer.class, args);
}
}
Now, at TaskSpringContext.class i want to create a bean based on the db-Field of the TaskTest-Annotation:
#Bean(name = "databaseService")
public DatabaseService databaseService()
{
return ??
Here i want to return the DatabaseServiceExtended
}
Anyone knows how to do it?
I assume that there's a better way for it, but this will scan your classpath, starting from "com.example" for all classes annotated with com.example.TaskTest and add a bean definition for it, so that bean will be created later.
This will allow you to check all classes for your annotation, but of course you will have to solve the problem that two (or more) #TaskTest could be on your classpath.
#Component
public class TestBeanProcessor implements BeanDefinitionRegistryPostProcessor {
#Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
; // does nothing
}
#Override
public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {
Set<BeanDefinition> definitions = scanForBeanDefinitionsIn("com.example"); // the base package
// test if one or more, perhaps error, whatever
BeanDefinition def = ...; // one of them
Class<?> clz = Class.forName(def.getBeanClassName());
TaskTest annotation = clz.getAnnotation(TaskTest.class);
// create new RootBeanDefinition with TaskText Data (pretty analogous to XML)
RootBeanDefinition dataSourceDefinition = ...;
registry.registerBeanDefinition("dataSource", dataSourceDefinition);
}
protected Set<BeanDefinition> scanForBeanDefinitionsIn(String basePackage) {
ClassPathScanningCandidateComponentProvider scanner = new ClassPathScanningCandidateComponentProvider(false);
scanner.addIncludeFilter(new TypeFilter() {
#Override
public boolean match(MetadataReader metadataReader, MetadataReaderFactory metadataReaderFactory) throws IOException {
return metadataReader.getAnnotationMetadata().getAnnotationTypes().contains("com.example.TaskTest");
}
});
return scanner.findCandidateComponents(basePackage);
}
}

What is the Spring DI equivalent of CDI's InjectionPoint?

I would like to create a Spring's bean producer method which is aware who invoked it, so I've started with the following code:
#Configuration
public class LoggerProvider {
#Bean
#Scope("prototype")
public Logger produceLogger() {
// get known WHAT bean/component invoked this producer
Class<?> clazz = ...
return LoggerFactory.getLogger(clazz);
}
}
How can I get the information who wants to get the bean injected?
I'm looking for some equivalent of CDI's InjectionPoint in Spring world.
Spring 4.3.0 enables InjectionPoint and DependencyDescriptor parameters for bean producing methods:
#Configuration
public class LoggerProvider {
#Bean
#Scope("prototype")
public Logger produceLogger(InjectionPoint injectionPoint) {
Class<?> clazz = injectionPoint.getMember().getDeclaringClass();
return LoggerFactory.getLogger(clazz);
}
}
By the way, the issue for this feature SPR-14033 links to a comment on a blog post which links to this question.
As far as I know, Spring does not have such a concept.
Then only thing that is aware of the point that is processed is a BeanPostProcessor.
Example:
#Target(PARAMETER)
#Retention(RUNTIME)
#Documented
public #interface Logger {}
public class LoggerInjectBeanPostProcessor implements BeanPostProcessor {
public Logger produceLogger() {
// get known WHAT bean/component invoked this producer
Class<?> clazz = ...
return LoggerFactory.getLogger(clazz);
}
#Override
public Object postProcessBeforeInitialization(final Object bean,
final String beanName) throws BeansException {
return bean;
}
#Override
public Object postProcessAfterInitialization(final Object bean,
final String beanName) throws BeansException {
ReflectionUtils.doWithFields(bean.getClass(),
new FieldCallback() {
#Override
public void doWith(final Field field) throws IllegalArgumentException, IllegalAccessException {
field.set(bean, produceLogger());
}
},
new ReflectionUtils.FieldFilter() {
#Override
public boolean matches(final Field field) {
return field.getAnnotation(Logger.class) != null;
}
});
return bean;
}
}

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