I'm working on AOP for the first time. It's not working - Maybe I'm mixing up Spring AOP and AspectJ, I'm not sure.
dependency declaration in Gradle file
dependencies {
compile fileTree(dir: 'libs', include: '*.jar')
...
compile("org.aspectj:aspectjweaver:1.8.9")
}
}
Configuration class
#Configuration
#EnableAspectJAutoProxy
public class AspectJConfiguration{
#Bean
public MailQueueServiceAspect mailQueueServiceAspect(){
return new MailQueueServiceAspect();
}
}
Aspect Class
#Aspect
public class MailQueueServiceAspect {
private final Logger log = LoggerFactory.getLogger(MailQueueServiceAspect.class);
#Pointcut("execution(* com.biscom.bsend.core.SaveMailHelper.aopTest())")
private void mailUpdatePointCut(){}
#After("mailUpdatePointCut()")
public void afterSampleCreation(JoinPoint joinPoint) {
log.info("Mail Queue updated successfully.");
}
}
Joint-Point holder class
public class SaveMailHelper extends AbstractHelper<SaveMailInput, SaveMailOutput> {
#Inject
private MailQueueService mailQueueService;
private final Logger log = LoggerFactory.getLogger(SaveMailHelper.class);
#Override
protected void executeHelper(SaveMailInput input, SaveMailOutput output) throws AbstractException {
MailQueue mailQueue = mailQueueService.get(input.getId(), new MailQueue());
BlockExecutor e = new BlockExecutor();
e.execute(input.getMailFrom().shouldSet(mailQueue.isNew(), mailQueue.getMailFrom()), () ->{
mailQueue.setMailFrom(input.getMailFrom().get());
});
output.setEntity(mailQueue);
aopTest();
}
public void aopTest(){
log.info("AOPTest method called.");
}
}
I also tried avoiding Configuration class by placing #Component annotation over Aspect class.
Related
Could someone give me advice, please, how to re-write some method using simple Spring (w/o Boot)?
Here I have some code methods:
1. createInjector
private Injector injector;
someMethod(){
injector = Guice.createInjector(new ExampleClass1(), new ExampleClass2());}
2 setModules(Modules.override
setModules(Modules.override(new ExampleClass3()).with(new ExampleClass4()));
//////////////////////////////////////////////////////////////////
public static void setModules(Module... modules) {
initInjector(modules);
}
private static void initInjector(Module... modules) {
injector = Guice.createInjector(modules);
}
}
Taking the risk that my answer is too general.
Roughly saying you can think Guice modules as equivalent a configuration class with #Configuration annotation, that contains #Bean etc.
The Guice injector can be considered as equivalent to the Spring ApplicationContext.
So for example if we have two configuration files:
#Configuration
public class ConfigA {
#Bean
ExampleClass1 exampleClass1(){
return new ExampleClass1();
}
#Bean
ExampleClass2 exampleClass2(){
return new ExampleClass2();
}
}
#Configuration
public class ConfigB {
#Bean
ExampleClass1 exampleClass1(){
return new ExampleClass1();
}
#Bean
ExampleClass3 exampleClass2(){
return new ExampleClass3();
}
}
And Services ExampleClass4 that you want as alternative of ExampleClass3.
You may use the #Primary annotation
public class ExampleClass4 extends ExampleClass3 {
#Override
public String toString() {
return "ExampleClass4{}";
}
}
#Configuration
public class ConfigC {
#Bean
#Primary
ExampleClass3 exampleClass3(){
return new ExampleClass4();
}
}
So rewriting the app to Spring (core 5.2, not Spring boot) will be:
public class App {
public static void main(String[] args) {
AnnotationConfigApplicationContext ap = initAppContext();
overrideBinding(ap);
System.out.println(ap.getBean(ExampleClass3.class));
//prints ExampleClass4{}
}
private static AnnotationConfigApplicationContext initAppContext() {
AnnotationConfigApplicationContext ap = new AnnotationConfigApplicationContext();
ap.register(ConfigA.class, ConfigB.class);
return ap;
}
private static void overrideBinding(AnnotationConfigApplicationContext ap) {
ap.register(ConfigC.class);
ap.refresh();
}
}
This technic of overriding a binding will work only because ExampleClass3 wasn't defined as primary, if it doesn't that would not work and you need to consider a different approach.
For more information:
https://www.baeldung.com/spring-application-context
https://docs.spring.io/spring-javaconfig/docs/1.0.0.m3/reference/html/modularizing-configurations.html
Override bean definition in java config
Since according to the docs #Component registers beans for the Spring container I'm trying to create a simple example of dependency injection using the following code:
package pl.playground;
//...
#SpringBootApplication
public class PlaygroundApplication {
#Autowired
private static Building building;
public static void main(String[] args) {
building.setBuildingSize(12L);
System.out.println(building.monthlyHeatingCost());
}
}
package pl.playground.facade;
//...
#Component
public class Building {
private HeatingService service;
private Long buildingSize;
#Autowired
public Building(HeatingService service) {
this.service = service;
}
public Double monthlyHeatingCost() {
return service.getMonthlyHeatingCost(buildingSize);
}
// getters & setters...
}
package pl.playground.service;
public interface HeatingService {
Double getMonthlyHeatingCost(Long size);
}
package pl.playground.service;
//...
#Component
public class HeatingServiceImpl implements HeatingService {
private final Double CUBIC_PRICE = 2.3;
public HeatingServiceImpl() {}
#Override
public Double getMonthlyHeatingCost(Long size) {
return size * CUBIC_PRICE;
}
}
It builds and runs, but there is a NullPointerException at building.setBuildingSize(12L);. However the one below works without any issues:
//PlaygroundApplication.java
package pl.playground;
//...
#SpringBootApplication
public class PlaygroundApplication {
public static void main(String[] args) {
AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(Config.class);
Building building = context.getBean(Building.class);
building.setBuildingSize(12L);
System.out.println(building.monthlyHeatingCost());
}
}
package pl.playground.config;
//...
#Configuration
public class Config {
#Bean
public Building building(HeatingService service) {
return new Building(service);
}
#Bean
public HeatingServiceImpl heatingServiceImpl() {
return new HeatingServiceImpl();
}
}
The rest is the same as before.
Why is #Component not creating Beans?
It is working the way I think it should when used inside a #Controller of a web app, does that make a difference? How does exactly #Bean and #Component differ?
What am I failing to understand?
EDIT
Consider the following scenario:
package pl.playground;
//...
#SpringBootApplication
public class ExampleApplication {
public static void main(String[] args) {
SpringApplication.run(ExampleApplication.class, args);
}
}
package pl.playground.controller;
//...
#Controller
public class Controller {
private Facade facade;
#Autowired
public Controller(Facade facade) {
this.facade = facade;
}
#GetMapping("/")
public String getIndexPage(Model model) {
return "index";
}
}
package pl.playground.facade;
//...
#Component
public class Facade {
private PostsService postService;
private UserService userService;
private TagService tagService;
#Autowired
public Facade(PostsService retrieve, UserService user, TagService tag) {
this.postService = retrieve;
this.userService = user;
this.tagService = tag;
}
//...
}
I don't need #Configuration here for it to work. That's my concern.
The problem with your code is that you are trying to #Autowire on a static field. You simply cannot do that. Look here: Can you use #Autowired with static fields?
It fails to work because the PlaygroundApplication class is not being created and managed by spring. The injection works only inside instances managed by spring. You can treat class annotated with #SpringBootApplication as configuration classes. Spring creates instances of those classes and injection works inside them but only on instance fields.
The second example shows the correct way to access spring beans from main method of the application.
Well. I used your original question and is working without any issues. #cezary-butler pointed out in the comments you can autowire into PlaygroundApplication but you can get hold of it easily in the static main method using context.getBean(Building.class)
#SpringBootApplication
public class PlaygroundApplication {
public static void main(String[] args) {
ConfigurableApplicationContext context =
SpringApplication.run(PlaygroundApplication.class);
Building building = context.getBean(Building.class);
building.setBuildingSize(12L);
System.out.println(building.monthlyHeatingCost());
}
}
Here is the sample repo https://github.com/kavi-kanap/stackoverflow-63072236
TLDR;
A Spring context needs to be created before any bean can be injected. In the first scenario, just the fact of having a #SpringBootApplication decorator does not ensure a context in the scope of the class it decorates.
SpringApplication.run(ExampleApplication.class, args); instantiates a context (and e.g. a web server among other things)
var context = new AnnotationConfigApplicationContext(Config.class); instantiates a scoped context
Thus the first example had null inside of Building as there was no context with the bean to inject.
wanner test spring boot(1.5.20) aop with minimum code
class being aopped,
#Component
public class Test {
public Test() {
System.out.println("test constr");
}
public void print() {
System.out.println("test print");
}
}
aop class
#Aspect
#Component
public class LoggingAspect {
public LoggingAspect() {
System.out.println("aspect constr");
}
#After("execution(* *.Test.*(..))")
public void log(JoinPoint joinPoint) {
System.out.println("aspect print");
}
}
main class
#SpringBootApplication
#EnableAspectJAutoProxy(proxyTargetClass = true)
public class AopApplication implements CommandLineRunner {
public static void main(String[] args) {
SpringApplication.run(AopApplication.class, args);
}
#Autowired
private Test test;
#Override
public void run(String... strings) throws Exception {
test.print();
}
}
both Test bean and LoggingAspect bean is created. Test.pring is executed. However, the pointcut log() is never triggered. I searched so and found no answer. I also tried #EnableAspectJAutoProxy with proxyTargetClass = True or False. In my understanding this params force to use cglib for Test class.
please let me know what I missed
figure out. change from .Test. to com.example.aop.Test.*, then works.
I'm trying to figure out how to build a Spring Boot standalone app. Of course to have things autowired requires some initial context starting point. If I just try to Autowire a class to run a job it is null even if I make it static.
Is there a way to use Spring #Services in a standalone non-web app?
#SpringBootApplication
public class MyApplication {
#Autowired
private static JobRunnerService job;
public static void main(String[] args) {
SpringApplication.run(MyApplication.class, args);
job.send(); //job is null !
}
}
So first wired in a static JobRunnerService to the main running MyApplication the JobRunner(Service) Class has a non-static SshSessionService wired into it.
the SshSession(Service) finally just has a no-arg constructor.
#Service("jobRunnerService")
public final class JobRunner implements JobRunnerService{
#Autowired
private SshSessionService ssh;
#Autowired
public JobRunner(SshSessionService ssh){
this.ssh = ssh;
}
public void sendToAgent() { ....
}
#Service("sshSessionService")
public class SshSession implements SshSessionService {
public SshSession() {
}
}
It starts off being null at the JobRunnerService job reference.
Several different solutions comes to mind:
If you take a look at the SpringApplication.run() method you will notice that it returns a ApplicationContext. From that, you can fetch the JobRunnerService, e.g.
#SpringBootApplication
public class MyApplication {
public static void main(String[] args) {
ApplicationContext ctx = SpringApplication.run(MyApplication.class, args);
JobRunnerService job = ctx.getBean(JobRunnerService.class);
job.send();
}
}
Another solution is to use #PostConstruct annotation for the send() method:
#Service("jobRunnerService")
public class JobRunner implements JobRunnerService {
#PostConstruct
public void send() { ... }
}
However in your case, I would implement the ApplicationRunner interface, either as a separate bean which autowires the JobRunnerService and then calls its send() method
#Component
public class SendRunner implements ApplicationRunner {
#Autowired
private JobRunnerService job;
#Override
public void run(ApplicationArguments args) {
job.send();
}
}
or let the JobRunner implement the ApplicationRunner interface directly:
#Service("jobRunnerService")
public class JobRunner implements JobRunnerService, ApplicationRunner {
#Override
public void send() { ... }
#Override
public void run(ApplicationArguments args) {
send();
}
}
You haven't provided the code for JobRunnerService but I am assuming it has a default constructor and that it is annotated by #Component for Spring to figure it out as a bean before you can actually autowire it. your job is null probably because it's not able to find an autowired bean for JobRunnerService and that's probably because you don't have an identifier for Spring to scan and create bean of type JobRunnerService
You can use #Servicesor #Component to the JobRunnerService class then add annotation #ComponentScan("package of JobRunnerService") below #SpringBootApplication, see this link:
How to scan multiple paths using the #ComponentScan annotation?
You need a few steps to get your standalone app working:
A class with main() method.
A #SpringBootApplication annotation to your main class.
And a call to the SpringApplication.run() method.
package com.example.myproject;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication // same as #Configuration #EnableAutoConfiguration #ComponentScan
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
As noted, the #SpringBootApplication is a composite annotation which consist of #Configuration #EnableAutoConfiguration and #ComponentScan. In other words, it can be replaced by the three latter annotations. Alternatively, you can use the alias scanBasePackage or scanBasePackageClasses to customize which directories that should be used for component scanning.
The example is copied from the #SpringBootApplication paragraph in the Spring Boot reference docs (see link above). If you would like to quick start your project, complete with build scripts (Maven or Gradle), dependencies, etc, you can generate a project skeleton using the Spring Initializr
I'm trying to run as Thread/runnable now as mentioned in the Spring document 3. Task Execution and Scheduling..
import org.springframework.core.task.TaskExecutor;
public class TaskExecutorExample {
private class MessagePrinterTask implements Runnable {
private String message;
public MessagePrinterTask(String message) {
this.message = message;
}
public void run() {
System.out.println(message);
}
}
private TaskExecutor taskExecutor;
public TaskExecutorExample(TaskExecutor taskExecutor) {
this.taskExecutor = taskExecutor;
}
public void printMessages() {
for(int i = 0; i < 25; i++) {
taskExecutor.execute(new MessagePrinterTask("Message" + i));
}
}
}
So in my case I'm trying...
#Service("jobRunnerService")
#Component
public class JobRunner implements JobRunnerService, ApplicationRunner{
#Autowired
public TaskExecutor taskExecutor;
#Autowired
private SshSessionService ssh;
private class JobTask implements Runnable{
public void run(){
Boolean success = connectToAgent();
if(success){
log.debug("CONNECTED!!!");
}
}
}
/**
* Construct JobRunner with TaskExecutor
* #param taskExecutor
*/
#Autowired
public JobRunner(TaskExecutor taskExecutor, SshSessionService ssh) {
this.taskExecutor = taskExecutor;
this.ssh = ssh;
}
private Map<String, String> sessionParams;
private final Logger log = LoggerFactory.getLogger(this.getClass());
#Override
public void run(ApplicationArguments args) {
/**
* Starting point of application
*
*/
taskExecutor.execute(new JobTask());
}
just getting org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.springframework.core.task.TaskExecutor] found for dependency
How can i get the imported lib to be accepted as a TaskExecutor Bean ??
I'm using Spring Boot 1.3.2, and I notice problem, ComponentScan in my test class is not working. And I want to mock some of Spring Beans. Is spring boot blocking ComponentScan?
Test config class:
#Configuration
#ComponentScan(value = {"myapp.offer", "myapp.image"})
public class TestEdge2EdgeConfiguration {
#Bean
#Primary
public OfferRepository offerRepository() {
return mock(OfferRepository.class);
}
}
Test class:
#ContextConfiguration(classes=TestEdge2EdgeConfiguration.class, loader=AnnotationConfigContextLoader.class)
public class OfferActionsControllerTest extends AbstractTestNGSpringContextTests {
#Autowired
private OfferRepository offerRepository;
#Autowired
private OfferActionsController offerActionsController;
#BeforeMethod
public void setUp(){
MockitoAnnotations.initMocks(this);
}
#Test
public void saveOffer() {
//given
BDDMockito.given(offerRepository.save(any(Offer.class))).willReturn(new Offer());
//when
ResponseEntity<Offer> save = offerActionsController.save(new Offer());
//then
org.springframework.util.Assert.notNull(save);
}
}
Solution of this problem
Test config class, it's important to exclude SpringBootApplicationConfigutation and add #ComponentScan:
#ComponentScan(basePackages = "com.example", excludeFilters =
#ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE,
value = {SpringBootApplicationConfigutation.class, MyDao.class}
)
)
#Configuration
public class TestEdge2EdgeConfiguration {
#Bean
public OfferRepository offerRepository() {
return mock(OfferRepository.class);
}
}
And test:
#SpringApplicationConfiguration(classes=TestEdge2EdgeConfiguration.class)
public class OfferActionsControllerTest extends AbstractTestNGSpringContextTests {
#Autowired
private OfferRepository offerRepository;
#Autowired
private OfferActionsController offerActionsController;
#BeforeMethod
public void resetMock() {
Mockito.reset(offerRepository);
}
#Test
public void saveOffer() {
//given
BDDMockito.given(offerRepository.save(any(Offer.class))).willReturn(new Offer());
//when
ResponseEntity<Offer> save = offerActionsController.save(new Offer());
//then
org.springframework.util.Assert.notNull(save);
}
}