I want to use a mechanism for create a one time compute function. I try to use Spring Caching. But it does not working. Please help me to solve this problem. My code like as below,
Gradle Dependency
compile 'org.springframework.boot:spring-boot-starter-cache'
Main Class of Spring Boot Application
#SpringBootApplication
#EnableCaching
public class Application {
public static ApplicationContext applicationContext;
public static void main(String[] args) {
TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
// todo: Try to save response text and request body
applicationContext = SpringApplication.run(Application.class, args);
}
#Bean
WebMvcConfigurer webMvcConfigurer(){
return new WebMvcConfigurer() {
#Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
registry
.addResourceHandler("/**")
.addResourceLocations("classpath:/")
.setCacheControl(CacheControl.maxAge(3600, TimeUnit.SECONDS).noTransform().mustRevalidate());
}
};
}
}
My Coputational property and Test method
public String test(){
return hello();
}
#Cacheable("hello")
public String hello(){
System.out.println("hello");
return "Hello";
}
The #Cacheable annotation caches the values when it is called from outside your #Bean so calling it from another method inside your bean will not work.
try something like
#Bean
public class CachingBean {
#Cacheable("hello")
public String hello(){
System.out.println("hello");
return "Hello";
}
}
#Service
public class CallerService {
#Autowired
private CachingBean cachingBean;
// Setters, constructors...
public String test(){
return cachingBean.hello();
}
}
And then it should work.
That's because the #Cacheable annotation creates a proxy around the method call when it is injected as a Bean, so a direct call (to an instance created directly) or an internal call are not intercepted and the caching mechanism does not even see those calls.
I still sometimes forget about it and get biten by it at the beginning :).
Cheers!
Related
Problem with correct class setting for tests.
I have the following service structure
My service:
Interface
public interface ColumnsFromTableService {
List<ColumnsDto> getTableColumnsFromSource(DataProvider dataProvider, String tableName);
DataProviderSourceType myDataProviderSourceType();
#Autowired
default void regMe(ColumnsFromTableFacade columnsFromTableFacade){
columnsFromTableFacade.register(myDataProviderSourceType(),this);
}
}
Impl
#Service
#RequiredArgsConstructor
public class OracleColumnsFromTableServiceImpl implements ColumnsFromTableService {
private final DataProviderInsideDao dataProviderInsideDao;
#Override
public List<ColumnsDto> getTableColumnsFromSource(DataProvider dataProvider, String tableName) {
return dataProviderInsideDao.getColumnsByTableNameFromOracle(dataProvider, tableName);
}
#Override
public DataProviderSourceType myDataProviderSourceType() {
return DataProviderSourceType.ORACLE;
}
}
My facade:
Interface
public interface ColumnsFromTableFacade {
List<ColumnsDto> getTableColumnsFromSource(DataProvider dataProvider, String tableName);
void register(DataProviderSourceType dataProviderSourceType, ColumnsFromTableService columnsDataProviderService);
}
Impl
#Service
public class ColumnsFromTableFacadeImpl implements ColumnsFromTableFacade {
private final Map<DataProviderSourceType, ColumnsFromTableService> implementationMap = new HashMap<>();
#Override
public List<ColumnsDto> getTableColumnsFromSource(DataProvider dataProvider, String tableName) {
ColumnsFromTableService columnsFromTableService = implementationMap.get(dataProvider.getSourceType());
return columnsFromTableService.getTableColumnsFromSource(dataProvider,tableName);
}
#Override
public void register(DataProviderSourceType dataProviderSourceType, ColumnsFromTableService columnsDataProviderService) {
implementationMap.put(dataProviderSourceType, columnsDataProviderService);
}
}
For use, I inject the facade in the place I need.
Everything works in the application. When creating ColumnsFromTableService beans, Spring Boot sees the #Autowired annotation in the interface and and registers the service in the facade. But when testing this facade, I can't set it up correctly.
My test:
#ExtendWith(MockitoExtension.class)
public class EasyServiceTest {
#InjectMocks
TablesFromSourceFacadeImpl tablesFromSourceFacade;
#Test
void test(){
tablesFromSourceFacade.getAllTablesFromSource(new DataProvider());
}
}
When running the test, the facade is successfully instantiated. But the collection with implementations is empty.
enter image description here
I am using
Junit jupiter - 5.7.1
Spring boot - 2.4.3
I decided to be rough
#ExtendWith(MockitoExtension.class)
public class EasyServiceTest {
TablesFromSourceFacadeImpl tablesFromSourceFacade;
#InjectMocks
OracleTablesFromSourceServiceImpl oracleTablesFromSourceService;
#InjectMocks
OracleColumnsFromTableServiceImpl oracleColumnsFromTableService;
#BeforeEach
void setUp() {
tablesFromSourceFacade = new TablesFromSourceFacadeImpl();
tablesFromSourceFacade.register(postgresTablesFromSourceService.myDataProviderSourceType(),
postgresTablesFromSourceService);
tablesFromSourceFacade.register(oracleTablesFromSourceService.myDataProviderSourceType(),
oracleTablesFromSourceService);
}
#Test
void test(){
tablesFromSourceFacade.getAllTablesFromSource(new DataProvider());
}
}
UPDATED
The second solution to the problem is to raise either the entire context of the spring, or part of it. But in my case, this did not work, since the services are scattered across different packages, and I would have to raise the entire context, which is heavy.
I have a particular class used to interface with a service that requires initialization. In the application lifecycle, the only place this makes sense is in the start of the application because the rest of the spring application cannot run without it. I had the idea to do this:
#SpringBootApplication
public class MyApplication {
public static void main(String[] args) {
try {
MyRequiredService mrs = new MyRequiredService();
mrs.connect(); // This will throw if it fails
run(MyApplication.class, args);
} catch(MyException e) {
System.out.println("Failed to connect to MyRequiredService!");
}
}
}
This will launch the service and attempt to connect but I have one big problem. How do I pass this class around the application? I need it's functions in the service endpoints I am writing.
I didn't see anything obvious and searching "passing class instance in spring boot application" turns up a bunch of unrelated topics.
Is there a smart, clean way to do this in spring boot? I apologize for a contrived example. The names of the service are unique enough I didn't want to violate any agreements.
You can make Spring do this for you. First, you need to annotate your class with #Service, so Spring will pick it up when scanning for classes.
Then, define an init() method and annotate it with #PostConstruct. Spring will instantiate your MyRequiredService class and call init()
#Service
public class MyRequiredService {
#PostConstruct
public void init() {
connect();
}
public void connect() {
// ...
}
}
You could call connect() from the constructor, but I don't like to define objects that may throw exceptions out of the constructor.
And then, you can use MyRequiredService in some other class by injecting it via the #Autowired annotation:
#Component
public class MyOtherClass {
private final MyRequiredService service;
public MyOtherClass(final MyRequiredService service) {
this.service = service;
}
// Other methods here.
}
This has the same overall effect as what you're trying to do above. If MyRequiredService fails, the application will not start up.
Make it a bean. Then it will be in the ApplicationContext which then you can pass to your desired other classes through the constructor
#Configuration
public class ApplicationConfiguration
{
#Bean
public MyRequiredService myRequiredService()
{
MyRequiredService mrs = new MyRequiredService();
try {
mrs.connect(); // This will throw if it fails
return mrs;
} catch(MyException e) {
log.error("Failed to connect to MyRequiredService!");
throw new IllegalStateException("MyRequiredService failed connection. Stopping startup");
}
}
#Bean
public SomeOtherService someOtherService(MyRequiredService mrs) {
return new SomeOtherService(mrs);
}
}
IMHO Instead of catching the error and logging it. I would throw it and stop the application from starting, but to keep with your example I added the throw IllegalStateException after the log.
Doing it this way Spring will create your MyRequiredService bean in the ApplicationContext then you can see I added as a parameter needed by the bean below that. Spring will grab that bean out of the ApplicationContext and supply it to the bean. If Spring doesn't find the bean in the ApplicationContext it will throw an error and stop the application from startup.
a class implements BeanFactoryPostProcessor which is init before normal bean
#Configuration
public class MyRequiredService implements BeanFactoryPostProcessor,
PriorityOrdered, InitializingBean {
#Override
public int getOrder() {
return Integer.MIN_VALUE;
}
public void connect() {
// ...
}
#Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
}
#Override
public void afterPropertiesSet() throws Exception {
connect();
}
}
Testing out Aspect #Before annotation in a Spring Boot application and it is not working. No Errors thrown. Just simply not working. It is a very simple rest service as below. Been at it for some time now and any tutorials and answers here seems to point that this is correct. My rest service returns correctly. Just that the message from Aspect doesn't print. I am very confident my package structure is correct. Please advice.
#SpringBootApplication
#EnableAspectJAutoProxy(proxyTargetClass = true)
public class StuffApplication {
public static void main(String[] args) {
SpringApplication.run(StuffApplication.class, args);
}
}
#RestController
#RequestMapping("/information")
public class ContentController {
#GetMapping("/person")
public People getPerson(Model model){
log(); // expecting the aspect print to occur when I call this.
// some logic to get personList which works fine
return new People(personList);
}
public void log(){
System.out.println("This is a logger");
}
}
#Aspect
#Component
public class JsonAspect {
#Before(value = "execution(* com.example.stuff.controller.ContentController.log())")
public void printBefore(){
System.out.println("I was called before the logger"); // never prints when I call log method
}
}
Case 1
Let's consider the following Spring configuration:
#Configuration
public class MyConf1 {
#Bean
public Foo getFoo() {
// Foo class is defined as part of an external lib.
return new Foo();
}
#Bean
public Bar getBar() {
return new Bar(getFoo());
}
}
For some reasons, I need to invoke a Foo's method (i.e. myFoo.shutdown();) when MyConf1 is destroyed.
Is there any way to perform this operation without retrieving the bean instance directly from the application context (via ApplicationContext.getBean())?
Case 2
Again, let's consider a second Spring configuration class:
#Configuration
public class MyConf2 {
#Bean
public ScheduledJob scheduledJob() {
Timer jobTimer = new Timer(true);
return new ScheduledJob(jobTimer);
}
}
This time, I need to invoke jobTimer.cancel() before destroying MyConf2. Indeed, I can instantiate jobTimer outside scheduledJob(), or making it a method's parameter, as scheduledJob(Timer jobTimer).
It will then be possible to define a proper destroyer method for MyConf2. However, I would like to know if there are other ways to proceed.
Any good suggestion?
Note: Foo, Bar, Timer, ScheduledJob classes are defined externally. Thus, there is no possibility to explicitly define an inner destroy method. As assumption, I can modify only MyConf1 and MyConf2.
I would suggest defining a destroy() method (annotated with #PreDestroy) in Foo class
Similarly, modify ScheduledJob class like
public class ScheduledJob {
private Timer timer;
public ScheduledJob(Timer timer){
this.timer = timer;
}
#PreDestroy
public void destroy(){
timer.cancel();
}
}
And add destroyMethod param in #Bean
#Configuration
public class MyConf2 {
#Bean(destroyMethod = "destroy")
public ScheduledJob scheduledJob() {
Timer jobTimer = new Timer(true);
return new ScheduledJob(jobTimer);
}
}
Please see the following page http://forum.spring.io/forum/spring-projects/container/48426-postconstruct-and-predestroy-in-javaconfig
DisposableBean should help you with case #1.
You can implement the DestructionAwareBeanPostProcessor interface that can adds a before-destruction callback when the bean is destroy.In that interface,the method postProcessBeforeDestruction is do that,see the following:
#Override
public void postProcessBeforeDestruction(Object bean, String beanName) throws BeansException {
System.out.println("before destory:"+bean);
}
#Override
public boolean requiresDestruction(Object bean) {
return true;
}
Pay attention to that the method requiresDestruction should return true,otherwise the method postProcessBeforeDestruction will not call when bean should destroy.
And i have a test:
public static void main(String[] args){
ClassPathXmlApplicationContext applicationContext=new ClassPathXmlApplicationContext("classpath:application-main.xml");
applicationContext.registerShutdownHook();
}
The postProcessBeforeDestruction really call when the bean is destroy.The output is :
before destory:com.zhuyiren.spring.learn.util.Handler#55141def
before destory:com.zhuyiren.spring.learn.controller.TestControleler#47eaca72
before destory:com.zhuyiren.spring.learn.service.impl.TestServiceImpl#7b2bbc3
before destory:com.zhuyiren.spring.learn.service.impl.TwoServiceImpl#48f2bd5b
before destory:com.zhuyiren.spring.learn.controller.ConverConroller#72967906
before destory:org.springframework.context.event.DefaultEventListenerFactory#1a482e36
before destory:org.springframework.context.event.EventListenerMethodProcessor#77fbd92c
I have a Java Spring Configuration class like this. I want to set a variable that several of my beans depend on, turn it into a bean, and use it as a dependency. How can I make the setVariable() method happen first? I'm converting my code from Guice, where this variable was being set in the overridden 'Configuration' method. Does Spring have something like that?
#Configuration
class SpringConfiguration{
String variable;
public void setVariable(){
variable = System.getenv("whatever")
}
#Bean
public void variable(){
return variable;
}
#Bean
public void myService(){
return new MyService(variable);
}
#Bean
public void myService2(){
return new MyService2(variable);
}
You can do something like this :
#Configuration
class SpringConfiguration {
#Bean(name="variable")
public String geVariable() {
return System.getenv("whatever");
}
#Bean
#DependsOn("variable")
public MyService getMyService() {
return new MyService(geVariable());
}
#Bean
#DependsOn("variable")
public MyService2 getMyService2() {
return new MyService2(geVariable());
}
}
Like that you can insure that variable will be initialized before service1 and service2, note that DependsOn in this case is just for clarification purposes.