I am new to Spring AOP and annotations. I tried to write a simple program that uses Aspect. I am unable to figure out where I went wrong. Its doesn't print the what I have in my Aspect.
package com.business.main;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
#EnableAspectJAutoProxy
#Configuration
public class PrintMain {
public static void main(String[] args) {
// Do I always need to have this. Can't I just use #Autowired to get beans
ApplicationContext ctx = new AnnotationConfigApplicationContext(PrintMain.class);
CheckService ck = (CheckService)ctx.getBean("service");
ck.print();
}
#Bean(name="service")
public CheckService service(){
return new CheckService();
}
}
package com.business.main;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
#Aspect
#Component
public class SimpleAspect {
#Around("execution(* com.business.main.CheckService.*(..))")
public void applyAdvice(){
System.out.println("Aspect executed");
}
}
package com.business.main;
import org.springframework.stereotype.Component;
#Component
public class CheckService{
public void print(){
System.out.println("Executed service method");
}
}
Output: Executed service method
I expect to print what I have in my Aspect
I think your #Component isn't work!
Maybe, you need the #ComponentScan
#EnableAspectJAutoProxy
#ComponentScan
#Configuration
public class PrintMain {
public static void main(String[] args) {
// Do I always need to have this. Can't I just use #Autowired to get beans
ApplicationContext ctx = new AnnotationConfigApplicationContext(TNGPrintMain.class);
CheckService ck = (CheckService)ctx.getBean("service");
ck.print();
}
#Bean(name="service")
public CheckService service(){
return new CheckService();
}
}
Related
My intention is run the aspect before get message method in service. I don't want to use xml configuration, so I add (hopefully) necessary annotation. But, when I run my application, aspect doesen't work, and nothing happen. Can You explain me why?
Service
public interface Service {
void getMessage();
}
Service implementation
import org.springframework.stereotype.Component;
#Service
public class ServiceImpl implements Service {
public void getMessage() {
System.out.println("Hello world");
}
}
Aspect
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
#Aspect
public class LoggingAspect {
#Before("execution(* com.example.aop.Service.getMessage())")
public void logBefore(JoinPoint joinPoint) {
System.out.println("AOP is working!!!");
}
}
Run
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
#SpringBootApplication
#EnableAspectJAutoProxy(proxyTargetClass=true)
#ComponentScan("com.example")
public class AopApplication {
public static void main(String[] args) {
final ConfigurableApplicationContext run = SpringApplication.run(AopApplication.class, args);
final Service bean = run.getBean(ServiceImpl.class);
bean.getMessage();
}
}
Output
Only Hello world
Probably, you have to add #Component annotation to LoggingAspect class.
I believe the pointcut expression syntax should be like this:
#Before("execution(void com.aop.service.Service+.getMessage(..))")
The + is used to apply the pointcut to subtypes (you can replace void with * too.
AppConfig contains Java Configuration.
package com.wh;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableLoadTimeWeaving;
import org.springframework.context.annotation.EnableLoadTimeWeaving.AspectJWeaving;
import org.springframework.context.annotation.Lazy;
import org.springframework.context.annotation.aspectj.EnableSpringConfigured;
#Configuration
#EnableSpringConfigured
#EnableLoadTimeWeaving(aspectjWeaving=AspectJWeaving.ENABLED)
public class AppConfig {
#Bean
#Lazy
public EchoService echoService(){
return new EchoService();
}
#Bean
public InstrumentationLoadTimeWeaver loadTimeWeaver() throws Throwable {
InstrumentationLoadTimeWeaver loadTimeWeaver = new InstrumentationLoadTimeWeaver();
return loadTimeWeaver;
}
}
Service Class
package com.wh;
import org.springframework.stereotype.Service;
#Service
public class EchoService {
public void echo( String s ) {
System.out.println( s );
}
}
EchoDelegateService is the Non Bean class in which we have Autowired The required Bean.
We expect that the EchoService should get autowired.
Problem : EchoService not getting autowired. Gives an Null Pointer exception.
package com.wh;
import org.springframework.beans.factory.annotation.Autowire;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Configurable;
#Configurable( preConstruction = true, autowire = Autowire.BY_TYPE, dependencyCheck = false )
public class EchoDelegateService {
#Autowired
private EchoService echoService;
public void echo( String s ) {
echoService.echo( s );
}
}
Main Class where we are calling method of NonBean Class.
package com.wh;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
public class MainApp {
public static void main(String[] args) {
ApplicationContext ctx =
new AnnotationConfigApplicationContext(AppConfig.class);
new EchoDelegateService().echo("hihi, it works...");
}
}
Your question already includes the answer: "... in a non-bean class". This simply does not work. All the autowiring, aspect resolving and whatever is to that, only works for beans. Thus, you definitely need to construct your EchoDelegateService via the spring factory:
EchoDelegateService myService = ctx.getBean(EchoDelegateService.class);
myService.echo("this should really work now");
I am learning spring the from book the "Spring in Action fourth edition" by Craig Walls. I am trying to apply advice to the method declared by the interface and I am getting Exception. When I apply the same advice to the class which doesn't implement anything, everything works fine.
Spring version - 4.3.2
Help would be appreciated.
Exception:
Exception in thread "main"org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.fifczan.bean.UserService] is defined
Code:
Interface:
package com.fifczan.bean;
public interface Service {
void doTask();
}
Implementation:
package com.fifczan.bean;
import org.springframework.stereotype.Component;
#Component
public class UserService implements Service {
public void doTask() {
System.out.println("doing task");
}
}
Aspect:
package com.fifczan;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.springframework.stereotype.Component;
#Aspect
#Component
public class UserAspect {
//If i change Service(interface) to UserService(implementation)
//in pointcut I am getting the same exception
#Before("execution(* com.fifczan.bean.Service.doTask(..))")
public void userAdvice(){
System.out.println("doing sth before method doTask");
}
}
Configuration:
package com.fifczan;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
#Configuration
#EnableAspectJAutoProxy
#ComponentScan
public class AspectJAutoProxyConfig {
}
main :
package com.fifczan;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import com.fifczan.bean.UserService;
public class AspectJAutoProxyTest {
public static void main(String[] args) {
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(AspectJAutoProxyConfig.class);
UserService userService= ctx.getBean(UserService.class);
userService.doTask();
}
}
You're asking for a bean of UserService, which is the concrete class, not the interface. Retrieve or inject a bean of type Service.
I'm trying to put together an SDK that uses Spring internally through a context it manages of its own. I want the jar that gets built to be usable regardless of whether or not Spring is in use on the application that wants to use the SDK.
I have something that works when it is running on its own. However if I attempt to use the SDK inside another Spring context (in my case a Spring Boot based application) I get a org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type exception.
Try as I might I cannot understand how to get this working, or indeed what I am doing wrong. The classes below show what I'm doing, the org.example.testapp.MySDKTest fails with the exception while the org.example.test.MySDKTest successfully passes. Sorry there is so much code but I can't reproduce the issue with a simplified case.
SDK source
package org.example.mysdk;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.example.mysdk.MyService;
import org.example.mysdk.MyServiceConfiguration;
public final class MySDK {
private static ApplicationContext applicationContext;
public static <T extends MyService> T getService(Class<? extends MyService> clazz, MyServiceConfiguration configuration) {
T tmp = (T) getApplicationContext().getBean(clazz);
tmp.setConfiguration(configuration);
return tmp;
}
private static ApplicationContext getApplicationContext() {
if (applicationContext == null) {
applicationContext = new AnnotationConfigApplicationContext(SpringContext.class);
}
return applicationContext;
}
}
.
package org.example.mysdk;
import org.springframework.beans.factory.annotation.Autowired;
public abstract class MyService {
private MyServiceConfiguration configuration;
#Autowired
private MyAutowiredService myAutowiredService;
MyService() {
}
MyService(MyServiceConfiguration configuration) {
super();
this.configuration = configuration;
}
public MyServiceConfiguration getConfiguration() {
return configuration;
}
void setConfiguration(MyServiceConfiguration configuration) {
this.configuration = configuration;
}
String getSomething(String in) {
return "something + " + myAutowiredService.getThing(configuration.getValue()) + " and " + in;
}
}
.
package org.example.mysdk;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Service;
#Service
#Scope("prototype")
public class MyServiceImpl1 extends MyService {
public MyServiceImpl1() {
}
public MyServiceImpl1(MyServiceConfiguration configuration) {
super(configuration);
}
public String method1() {
return this.getSomething("method1");
}
}
.
package org.example.mysdk;
public class MyServiceConfiguration {
private String value;
public void setValue(String value) {
this.value = value;
}
public String getValue() {
return value;
}
}
.
package org.example.mysdk;
import org.springframework.stereotype.Service;
import javax.annotation.PostConstruct;
#Service
public class MyAutowiredService {
private String thing = "a value";
public String getThing(String in) {
return thing + " " + in;
}
#PostConstruct
void init() {
System.out.println("MyAutowiredService bean created");
}
}
.
package org.example.mysdk;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
#Configuration
#ComponentScan(basePackages = {
"org.example.mysdk"
})
public class SpringContext {
}
Tests
This first test fails with a org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type exception,
package org.example.testapp;
import static org.junit.Assert.*;
import org.example.mysdk.MyServiceConfiguration;
import org.example.mysdk.MyServiceImpl1;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.support.AnnotationConfigContextLoader;
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = App.class, loader = AnnotationConfigContextLoader.class)
public class MySDKTest {
#Autowired
MyServiceImpl1 service;
#Test
public void test() {
MyServiceConfiguration conf = service.getConfiguration();
assertEquals(conf.getValue(), "this is the instance configuration");
}
}
.
package org.example.testapp;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.example.mysdk.MySDK;
import org.example.mysdk.MyServiceConfiguration;
import org.example.mysdk.MyServiceImpl1;
#Configuration
#ComponentScan(basePackages = {
"org.example.testapp"
})
public class App {
#Bean
public MyServiceImpl1 myServiceImpl1() {
MyServiceConfiguration configuration = new MyServiceConfiguration();
configuration.setValue("this is the instance configuration");
return MySDK.getService(MyServiceImpl1.class, configuration);
}
}
and this test succeeds,
package org.example.test;
import static org.junit.Assert.*;
import org.example.mysdk.MySDK;
import org.example.mysdk.MyServiceConfiguration;
import org.example.mysdk.MyServiceImpl1;
import org.junit.Test;
public class MySDKTest {
#Test
public void test() {
MyServiceConfiguration configuration = new MyServiceConfiguration();
configuration.setValue("this is the instance configuration");
MyServiceImpl1 service = MySDK.getService(MyServiceImpl1.class, configuration);
assertEquals(service.getConfiguration().getValue(), "this is the instance configuration");
}
}
If I've gone about this the completely wrong way I'm happy to hear suggestions of how this should be done differently!
You have to modify two files.
First App.java, it should scan for "org.example.mysdk" package to inject myAutowiredService in abstract class MyService, If not it has to be created in App.java. And the name of the MyServiceImpl1 bean must be different from myServiceImpl1 as it will conflict.
package org.example.testapp;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.example.mysdk.MySDK;
import org.example.mysdk.MyServiceConfiguration;
import org.example.mysdk.MyServiceImpl1;
#Configuration
#ComponentScan(basePackages = {
"org.example.testapp", "org.example.mysdk"
})
public class App {
#Bean
public MyServiceImpl1 myServiceImpl() {
MyServiceConfiguration configuration = new MyServiceConfiguration();
configuration.setValue("this is the instance configuration");
return MySDK.getService(MyServiceImpl1.class, configuration);
}
}
Then secondly in MySDKTest.java should inject myServiceImpl which was created in App.java
import static org.junit.Assert.*;
import org.example.mysdk.MyServiceConfiguration;
import org.example.mysdk.MyServiceImpl1;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.support.AnnotationConfigContextLoader;
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = App.class, loader = AnnotationConfigContextLoader.class)
public class MySDKTest {
#Autowired
MyServiceImpl1 myServiceImpl;
#Test
public void createOxiAccountService() {
MyServiceConfiguration conf = myServiceImpl.getConfiguration();
assertEquals(conf.getValue(), "this is the instance configuration");
}
}
I have been trying to add spring validators to a spring-data-rest project.
I followed along and setup the "getting started" application via this link: http://spring.io/guides/gs/accessing-data-rest/
...and now I am trying to add a custom PeopleValidator by following the documents here:
http://docs.spring.io/spring-data/rest/docs/2.1.0.RELEASE/reference/html/validation-chapter.html
My custom PeopleValidator looks like
package hello;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
public class PeopleValidator implements Validator {
#Override
public boolean supports(Class<?> clazz) {
return true;
}
#Override
public void validate(Object target, Errors errors) {
errors.reject("DIE");
}
}
...and my Application.java class now looks like this
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
#Configuration
#EnableJpaRepositories
#Import(RepositoryRestMvcConfiguration.class)
#EnableAutoConfiguration
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public PeopleValidator beforeCreatePeopleValidator() {
return new PeopleValidator();
}
}
I would expect that POSTing to the http://localhost:8080/people URL would result in an error of some kind since the PeopleValidator is rejecting everything. However, no error is thrown, and the validator is never called.
I have also tried manually setting up the validator as shown in section 5.1 of the spring-data-rest documentation.
What am I missing?
So it appears that the before/after "save" events only fire on PUT and PATCH. When POSTing, the before/after "create" events fire.
I tried it the manual way again using the configureValidatingRepositoryEventListener override and it worked. I'm not sure what I'm doing differently at work than here at home. I'll have to look tomorrow.
I sure would love to hear if others have suggestions on why it wouldn't work.
For the record, here is what the new Application.java class looks like.
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.rest.core.event.ValidatingRepositoryEventListener;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
#Configuration
#EnableJpaRepositories
#Import(RepositoryRestMvcConfiguration.class)
#EnableAutoConfiguration
public class Application extends RepositoryRestMvcConfiguration {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Override
protected void configureValidatingRepositoryEventListener(ValidatingRepositoryEventListener validatingListener) {
validatingListener.addValidator("beforeCreate", new PeopleValidator());
}
}
Looks like the feature is currently not implemented (2.3.0), unluckily there are no constants for the event names otherwise the solution below would not be that fragile.
The Configuration adds all properly named Validator beans to ValidatingRepositoryEventListener using the right event.
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.ListableBeanFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.rest.core.event.ValidatingRepositoryEventListener;
import org.springframework.validation.Validator;
#Configuration
public class ValidatorRegistrar implements InitializingBean {
private static final List<String> EVENTS;
static {
List<String> events = new ArrayList<String>();
events.add("beforeCreate");
events.add("afterCreate");
events.add("beforeSave");
events.add("afterSave");
events.add("beforeLinkSave");
events.add("afterLinkSave");
events.add("beforeDelete");
events.add("afterDelete");
EVENTS = Collections.unmodifiableList(events);
}
#Autowired
ListableBeanFactory beanFactory;
#Autowired
ValidatingRepositoryEventListener validatingRepositoryEventListener;
#Override
public void afterPropertiesSet() throws Exception {
Map<String, Validator> validators = beanFactory.getBeansOfType(Validator.class);
for (Map.Entry<String, Validator> entry : validators.entrySet()) {
EVENTS.stream().filter(p -> entry.getKey().startsWith(p)).findFirst()
.ifPresent(p -> validatingRepositoryEventListener.addValidator(p, entry.getValue()));
}
}
}
A bit of a stab in the dark - I've not used spring-data-rest. However, after having a read of the tutorial you're following, I think the problem is that you need a PersonValidator not a PeopleValidator. Rename everything accordingly:
PersonValidator
package hello;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;
public class PersonValidator implements Validator {
#Override
public boolean supports(Class<?> clazz) {
return true;
}
#Override
public void validate(Object target, Errors errors) {
errors.reject("DIE");
}
}
Application
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
#Configuration
#EnableJpaRepositories
#Import(RepositoryRestMvcConfiguration.class)
#EnableAutoConfiguration
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public PersonValidator beforeCreatePersonValidator() {
return new PersonValidator();
}
}
Another way of doing it is to use annotated handlers as specified here
http://docs.spring.io/spring-data/rest/docs/2.1.0.RELEASE/reference/html/events-chapter.html#d5e443
Here is an example of how to use annotated handlers:
import gr.bytecode.restapp.model.Agent;
import org.springframework.data.rest.core.annotation.HandleBeforeCreate;
import org.springframework.data.rest.core.annotation.HandleBeforeSave;
import org.springframework.data.rest.core.annotation.RepositoryEventHandler;
import org.springframework.stereotype.Component;
#Component
#RepositoryEventHandler(Agent.class)
public class AgentEventHandler {
public static final String NEW_NAME = "**modified**";
#HandleBeforeCreate
public void handleBeforeCreates(Agent agent) {
agent.setName(NEW_NAME);
}
#HandleBeforeSave
public void handleBeforeSave(Agent agent) {
agent.setName(NEW_NAME + "..update");
}
}
Example is from github edited for brevity.