`
#RestController
public class TestController {
#Cacheable(cacheNames = "testCache", key = "#name")
#GetMapping("/test/{name}")
public String test(#PathVariable String name) {
System.out.println("########Test Called ###### " + name);
return HttpStatus.OK.toString();
}
}
Here cacheNames is Stirng array, if name is not exists in cacheNames then it should add first then shloud do rest of the things.
I'm using spring boot cache and I have to add cacheNames depend on request parameters.
You can do something like this if you want much flexibility:
import org.springframework.cache.CacheManager;
import org.springframework.cache.Cache;
// other imports
#RestController
public class TestController {
private final Cache myCache;
public TestController(#Autowired CacheManager cacheManager) {
this.myCache = cacheManager.getCache("myCache");
}
#GetMapping("/test/{name}")
public String test(#PathVariable String name) {
return myCache.get(name, () -> {
// your expensive operation that needs to be cached.
System.out.println("########Test Called ###### " + name);
return HttpStatus.OK.toString();
});
}
}
Cache name will not be dynamic in that case, but the cache key will be. And this is probably what you want.
Related
I am attempting to use Spring Boot Cache with a Caffeine cacheManager.
I have injected a service class into a controller like this:
#RestController
#RequestMapping("property")
public class PropertyController {
private final PropertyService propertyService;
#Autowired
public PropertyController(PropertyService propertyService) {
this.propertyService = propertyService;
}
#PostMapping("get")
public Property getPropertyByName(#RequestParam("name") String name) {
return propertyService.get(name);
}
}
and the PropertyService looks like this:
#CacheConfig(cacheNames = "property")
#Service
public class PropertyServiceImpl implements PropertyService {
private final PropertyRepository propertyRepository;
#Autowired
public PropertyServiceImpl(PropertyRepository propertyRepository) {
this.propertyRepository = propertyRepository;
}
#Override
public Property get(#NonNull String name, #Nullable String entity, #Nullable Long entityId) {
System.out.println("inside: " + name);
return propertyRepository.findByNameAndEntityAndEntityId(name, entity, entityId);
}
#Cacheable
#Override
public Property get(#NonNull String name) {
return get(name, null, null);
}
}
Now, when I call the RestController get endpoint and supply a value for the name, every request ends up doing inside the method that should be getting cached.
However, if I call the controller get endpoint but pass a hardcoded String into the service class method, like this:
#PostMapping("get")
public Property getPropertyByName(#RequestParam("name") String name) {
return propertyService.get("hardcoded");
}
Then the method is only invoked the first time, but not on subsequent calls.
What's going on here? Why is it not caching the method call when I supply a value dynamically?
Here is some configuration:
#Configuration
public class CacheConfiguration {
#Bean
public CacheManager cacheManager() {
val caffeineCacheManager = new CaffeineCacheManager("property", "another");
caffeineCacheManager.setCaffeine(caffeineCacheBuilder());
return caffeineCacheManager;
}
public Caffeine<Object, Object> caffeineCacheBuilder() {
return Caffeine.newBuilder()
.initialCapacity(200)
.maximumSize(500)
.weakKeys()
.recordStats();
}
}
2 solutions (they work for me):
remove .weakKeys()
propertyService.get(name.intern()) - wouldn't really do that, possibly a big cost
Sorry, but I don't have enough knowledge to explain this. Probably something to do with internal key representation by Caffeine.
Say we have a FileLoader Interface:
public interface FileLoader {
default String loadFile(String fileId) {
// Default business logic
return "Default implementation for FileLoader. Loading file" + fileId;
}
}
And different implementations for different countries:
public class USAFileLoader implements FileLoader {
#Override
public String loadFile(String fileId) {
// ... Specific business logic for USA
return "USA implementation for FileLoader. Loading file" + fileId;
}
}
public class FRAFileLoader implements FileLoader {
#Override
public String loadFile(String fileId) {
// ... Specific business logic for France
return "France implementation for FileLoader. Loading file" + fileId;
}
}
And we create an endpoint to load files:
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;
#RestController
public class FileUploadController {
FileLoader fileLoader;
#PostMapping("/load/{fileId}/{countryCode}")
public String loadFile(#PathVariable String fileId, #PathVariable String countryCode) {
fileLoader = ... // Inject the right loader based on countryCode
return fileLoader.loadFile(fileId);
}
}
How can I inject the right FileLoader at runtime for every request, based on countryCode? I've found something in Spring called FactoryBean that apparently may work, but I'm now sure if it's the right tool, or if this is the right way to address this problem. Also, I don't know how injection will behave with requests being proccessed at the same time.
The best thing you can do here using run time polymorphism, add one more abstract method in interface FileLoader for country code
public interface FileLoader {
default String loadFile(String fileId) {
// Default business logic
return "Default implementation for FileLoader. Loading file" + fileId;
}
public abstract String getCountryCode();
}
And then implement it in every implementation class with return the appropriate country code
public class USAFileLoader implements FileLoader {
#Override
public String loadFile(String fileId) {
// ... Specific business logic for USA
return "USA implementation for FileLoader. Loading file" + fileId;
}
public String getCountryCode(){
return "USA";
}
}
And then you can Autowire all beans of type FileLoader into List and call loadFile on appropriate bean
#RestController
public class FileUploadController {
#Autowire
List<FileLoader> fileLoaders;
#PostMapping("/load/{fileId}/{countryCode}")
public String loadFile(#PathVariable String fileId, #PathVariable String countryCode) {
return fileLoaders.stream()
.filter(f->f.getCountryCode().equlas(countryCode))
.findFirst()
.map(loader->loader.loadFile(fileId))
.orElse(()-> FileLoader.super.loadFile(fileId)); //calling interface default method
}
}
You can receive a bean with another way at runtime using ApplicationContext::getBean:
#Autowired
ApplicationContext
#PostMapping("/load/{fileId}/{countryCode}")
public String loadFile(#PathVariable String fileId, #PathVariable String countryCode) {
FileLoader fileloader = (FileLoader) applicationContext.getBean(countryCode);
return fileLoader.loadFile(fileId);
}
However, I'd recommend creating a service layer that aggregates the country-specific implementations and uses a factory pattern. There is nothing bad on such implementation.
I am implementing a Rest WS using Spring 4 (Spring Boot).
The basic idea is I want to consume a JSON payload specifying an identifier (e.g. social security number or something) and run multiple subServices on that identifier.
Here is a sample payload:
{
"ssNumber" : "1111111111111111",
"subServicesDetails" :
[
{ "subServiceName" : "Foo" , "requestParameters" : {} },
{ "subServiceName" : "Dummy", "requestParameters" : {} }
]
}
In my code I have multiple "sub-services" (FooService, DummyService) implementing the SubService interface:
package com.johnarnold.myws.service;
import com.johnarnold.myws.model.SubServiceDetails;
public interface SubService {
public boolean service(String ssNumber, SubServiceDetails ssd);
}
And below is the FooService code.
package com.johnarnold.myws.service;
import java.util.HashMap;
import java.util.Map;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import com.johnarnold.myws.dao.FooDao;
import com.johnarnold.myws.model.Foo;
import com.johnarnold.myws.model.SubServiceDetails;
#Component
public class FooService implements SubService{
private static Logger log = Logger.getLogger(FooService.class);
#Autowired
private FooDao dao;
public FooService()
{
log.debug("FooService ctor");
}
public boolean service(String ssNumber, SubServiceDetails ssd)
{
log.debug("FooService service");
Map <String, String> responseParameters = new HashMap<String, String>();
try
{
Foo foo = dao.getFoo(ssNumber);
if(foo.isCompromised())
{
responseParameters.put("listed", "true");
}
else
{
responseParameters.put("listed", "false");
}
ssd.setResponseParameters(responseParameters);
return true;
}
catch(Throwable ex)
{
log.error("Exception in service ", ex);
}
return false;
}
}
Now I wrote my own factory to create the subservices but when I did that of course because I am explictly creating my beans (e.g. FooService) below - my container is not auomatically injecting any of the #Autowired members - FooDao for example:
package com.johnarnold.myws.service;
public class SubServiceFactory {
/*
* Instantiates a SubService for the supplied subServiceName or throws an exception if
* no valid SubService exists
*/
public static SubService createSubService(String subServiceNameStr)
{
SubService subService = null;
System.out.println("subServiceName [" + subServiceNameStr + "]");
if(subServiceNameStr.equals("Foo"))
{
subService = new FooService();
}
if(subServiceNameStr.equals("Dummy"))
{
subService = new DummyService();
}
else
{
System.out.println("subServiceName [" + subServiceNameStr + "] is not defined");
}
return subService;
}
}
For completeness here is the Controller:
package com.johnarnold.myws.controller;
import javax.servlet.http.HttpServletRequest;
import javax.validation.Valid;
import org.apache.log4j.Logger;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import com.johnarnold.myws.model.RawsPayload;
import com.johnarnold.myws.model.SubServiceDetails;
import com.johnarnold.myws.service.SubService;
import com.johnarnold.myws.service.SubServiceFactory;
import com.johnarnold.myws.web.ValidMessage;
#RestController
#RequestMapping("/raws/")
public class RawsController {
private static final Logger logger = Logger.getLogger(RawsController.class);
//#Autowired
//SubService [] subSvcs;
#RequestMapping(value="/{version}/status", method=RequestMethod.GET)
public ResponseEntity<ValidMessage> getServiceStatus()
{
return new ResponseEntity<>(new ValidMessage() , HttpStatus.OK);
}
/*
* Main entry point - orchestrates all of the WS Sub Services
*/
#RequestMapping(value="/{version}/raws", method=RequestMethod.PUT)
public ResponseEntity<String> raws(#Valid #RequestBody RawsPayload rawsPayload,
HttpServletRequest request)
{
logger.info("Request received");
System.out.println("payl " + rawsPayload);
System.out.println("ssNumber=" + rawsPayload.getSsNumber());
System.out.println("sub svcs details=" + rawsPayload.getSubServicesDetails().length);
SubServiceDetails[] subServiceDetails = rawsPayload.getSubServicesDetails();
for(SubServiceDetails ssd : subServiceDetails)
{
String subServiceNameStr = ssd.getSubServiceName();
System.out.println("svcname=" + subServiceNameStr);
System.out.println("svc req params=" + ssd.getRequestParameters());
System.out.println("svc resp params=" + ssd.getResponseParameters());
SubService subService = SubServiceFactory.createSubService(subServiceNameStr);
// Probably wrap the below with some timings
subService.service(rawsPayload.getSsNumber(), ssd);
}
//System.out.println("svcs are " + subSvcs + "size=" + subSvcs.length);
return new ResponseEntity<>("foo" , HttpStatus.OK);
}
}
And here is the main payload class:
package com.johnarnold.myws.model;
import javax.validation.Valid;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import org.apache.log4j.Logger;
import org.hibernate.validator.constraints.Length;
public class RawsPayload {
static Logger log = Logger.getLogger(RawsPayload.class);
#NotNull
#Length(min=16, max=19)
private String ssNumber;
#Valid
#NotNull
#Size(min=1, max=3)
private SubServiceDetails [] subServicesDetails;
public String getSsNumber() {
return ssNumber;
}
public void setSsNumber(String ssNumber) {
log.info("setSsNumber()");
this.ssNumber = ssNumber;
}
public SubServiceDetails[] getSubServicesDetails() {
return subServicesDetails;
}
public void setSubServicesDetails(SubServiceDetails[] subServicesDetails) {
this.subServicesDetails = subServicesDetails;
}
}
I've read a number of answers on StackOverflow regarding Spring 4 Conditional Beans - but this functionality appears to be targeted at Context / Configuration type information rather than Request message content (as in this case).
Can anyone point me in the right direction. I can provide further context if necessary
KRgds
John
Two possible ways of solving this problem:
Add all your subService beans to the Spring context then select from them using a ServiceLocatorFactoryBean. This is the nicer approach (from architectural point of view), but it might require a bit more time to implement if you have never used this concept before.
There is a simpler alternative below if you want to stick with basic Spring solutions:
Have the subservice beans injected into your main service as a list, and then select from that. It would look something like this:
#Bean
public List<SubService> subServices(){
List<SubService> list = new SubService<>();
list.add(new AService());
list.add(new BService());
return list;
}
THEN
public SubService selectServiceByName() {
//iterate through the list, pick the service with the right name and return - this solution will require you to bind by beannames
}
#john-arnold First, crate all the services like this, or annotate them with #Service/#Component with explicit names like below: names are start with the values of subServiceName param and contains a common suffix, "Service" here, thats important.
#Bean("FooService")
public SubService fooService() {
return new FooService();
}
#Bean("DummyService")
public SubService dummyService() {
return new DummyService();
}
Then change your factory like this:
#Component
public class SubServiceFactory implements BeanFactoryAware{
private BeanFactory beanFactory;
private static final String MY_SERVICE_SUFFIX = "Service";
#Override
public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
this.beanFactory = beanFactory;
}
public <T> T getServiceImplementation(String name, Class<T> requiredType) {
return beanFactory.getBean(name + MY_SERVICE_SUFFIX, requiredType);
}
}
Now what we have here is a BeanFactoryAware class that you can inject to your Rest Endpoint and instead of if statement, try this:
subServiceFactory.getServiceImplementation(subServiceNameStr, SubService.class);
This will return your bean or an exception if it doesn't find one. If you don't want an exception, you can catch it and return null or you can create a Service imp. just for these and return that instance. Your choice.
Edit:
As a shortcut, you can define your imp. Beans and than add this to your rest endpoint
#Autowired
private Map<String, SubService> mySubServices;
Spring will automatically inject all your imp. ref. so you can just use get() method of the map. But i prefer the first one..
You don't need anything fancy here. Just implement all your services that implement your service interface, annotate them all with either #Component or #Service and scan them as usual.
Then, wherever you have to choose a concrete service implementation, autowire all implementations of your service like this:
#Autowired
Map<String, SubService> subServices;
The key of the map will be the name of the service as specified in the #Component annotation of every sub service implementation, and the value will be the instance.
So, when you receive you JSON, just get the name of the sub service (i.e. Foo), and get the specific service of the map:
SubService fooSubService = subServices.get(subServiceName + "Service");
where subServiceName is the uncapitalized name of the sub service you're receiving in your JSON (i.e. if you're receiving Foo this would be foo).
The convention is to use the uncapitalized name of the class that implements the interface as the bean name, i.e. for the FooService class the bean name will be fooService, and this is the key you have to look for in the map.
I'm new to Spring and following along the example at http://spring.io/guides/gs/consuming-rest.
I noticed they haven't mapped all the JSON elements from http://graph.facebook.com/pivotalsoftware so I wanted to extend the example a little. For this example, I wanted to add "likes" and "were_here_count", like so in Page.java:
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
#JsonIgnoreProperties(ignoreUnknown = true)
public class Page {
private String name;
private String about;
private String phone;
private String website;
private int were_here_count;
private int likes;
public String getName() {return name;}
public String getAbout() {return about;}
public String getPhone() {return phone;}
public String getWebsite() {return website;}
public int getVisitCount() {return were_here_count;}
public int getLikes() {return likes;}
}
and making these changes in Application.java:
import org.springframework.web.client.RestTemplate;
public class Application {
public static void main(String args[]) {
RestTemplate restTemplate = new RestTemplate();
Page page = restTemplate.getForObject("http://graph.facebook.com/pivotalsoftware", Page.class);
System.out.println("Name: " + page.getName());
System.out.println("About: " + page.getAbout());
System.out.println("Phone: " + page.getPhone());
System.out.println("Website: " + page.getWebsite());
System.out.println("Visit count: " + page.getVisitCount());
System.out.println("Likes: " + page.getLikes());
}
}
I was thinking that the mapping was done by element name, and that worked for "likes", but didn't for "were_here_count". Output:
Name: Pivotal
About: Pivotal is enabling the creation of modern software applications that leverage big & fast data – on a single, cloud independent platform.
Phone: (650) 286-8012
Website: http://www.pivotal.io
Visit count: 0
Likes: 1175
were_here_count is currently at 60. I'm guessing the default converter didn't like the underscore in the variable name. So I used the overloaded version of getForObject, providing my own mapping, like so:
package hello;
import java.util.HashMap;
import java.util.Map;
import org.springframework.web.client.RestTemplate;
public class Application {
public static void main(String args[]) {
RestTemplate restTemplate = new RestTemplate();
Map<String, String> variables = new HashMap<String, String>(3);
variables.put("name", "name");
variables.put("about", "about");
variables.put("phone", "phone");
variables.put("website", "website");
variables.put("were_here_count", "were_here_count");
variables.put("likes", "likes");
Page page = restTemplate.getForObject("http://graph.facebook.com/pivotalsoftware", Page.class, variables);
System.out.println("Name: " + page.getName());
System.out.println("About: " + page.getAbout());
System.out.println("Phone: " + page.getPhone());
System.out.println("Website: " + page.getWebsite());
System.out.println("Visit count: " + page.getVisitCount());
System.out.println("Likes: " + page.getLikes());
}
}
But all to no avail. I've seen a few examples regarding custom JSON converters here but didn't understand them well - plus, this is a much simpler example, could I not get this done with a simple String-String mapping of variable names?
Anyone know how to do this and willing to show me how to build a custom converter and what the necessary steps are? Thank you! :)
Try adding some of Jackson's annotations to your Page class to help with the deserialization of the JSON. You should be able to tell Jackson (which will handle serialization/deserialization of JSON in Spring by default), what attributes in the response JSON map to your POJO attributes.:
public class Page {
...
#JsonProperty("were_here_count")
private int wereHereCount;
...
}
Another option, if you are not sure what attributes are being returned, is to just map the JSON to a Map:
Map<String,Object> map = restTemplate.getForObject("http://graph.facebook.com/pivotalsoftware", Map.class);
for (Map.Entry entry: response.entrySet()){
// do stuff...
}
Sometime this is the easier way to do custom object mapping when the response JSON is convoluted or just doesn't deserialize easily.
What does your setter for Page looks like? It works for me with this setter:
public void setWere_here_count(int were_here_count) {
this.were_here_count = were_here_count;
}
I have configured a custom generic service DAO for my spring / hibernate project - the idea being that I can reuse it easily from my controllers.
It essentially looks like this:
public class DefaultService<T> {
private Class<T> e;
public String className(Class<T> e) {
String clip = e.getName();
clip = clip.substring(clip.lastIndexOf('.') + 1, clip.length());
return clip;
}
public List<T> getAll(Integer status) {
Session session = sessionFactory.getCurrentSession();
Query query = session.createQuery("FROM " + className(e) + " WHERE status = " + status);
return query.list();
}
...
Which gets referenced by:
#Autowired
public DefaultService<Address> addressService;
addressService.get(1);
However the String clip = e.getName() line throws a Null pointer exception. I can get this to work if I move the class into the attributes section (so addressService.get(Address.class, 1) but I find this somewhat untidy, especially when there are multiple different classes being called upon.
Is there some way to get the class to generate a value correctly without repeatedly adding it into all my functions?
Thanks in advance.
I did something similar, you need the generic class to be a constructor argument as well, mine uses hibernate entities, but you could pass in the string of table name.
public class DomainRepository<T> {
#Resource(name = "sessionFactory")
protected SessionFactory sessionFactory;
public DomainRepository(Class genericType) {
this.genericType = genericType;
}
#Transactional(readOnly = true)
public T get(final long id) {
return (T) sessionFactory.getCurrentSession().get(genericType, id);
}
You can then subclass (if you need to) to customize or simply set up you bean in the spring config like below t :
<bean id="tagRepository" class="com.yourcompnay.data.DomainRepository">
<constructor-arg value="com.yourcompnay.domain.Tag"/>
</bean>
So in your code you could then reference tagRepository like so (no other cod eis needed than that posted above, and below) :
#Resource(name = "tagRepository")
private DomainRepository<Tag> tagRepository;
Also, I would call it a repository not a service, a service deals with different types and their interactions (not just one). And for specifically your example using SQL strings :
public final String tableName;
public DomainRepository(String tableName) {
this.tableName = tableName;
}
public List<T> getAll(Integer status) {
Session session = sessionFactory.getCurrentSession();
Query query = session.createQuery("FROM " + tableName + " WHERE status = " + status);
return query.list();
}
and have your beans defined like so
<bean id="addressRepository" class="com.yourcompnay.data.DomainRepository">
<constructor-arg value="address"/>
</bean>
And then you can alsow create subclasses youself where necessary :
public class PersonRepository extends DomainRepository<Person> {
public PersonRepository(){
super("person"); //assumes table name is person
}
As I understand you got NPE because you did not set any value for this field.
So you can resolve this problem by 2 ways:
Set manually class object as in comment NimChimpsky.
Get class type dynamically. E.g, if you use Spring try this one:
protected Class getEntityClass() {
return GenericTypeResolver.resolveTypeArguments(getClass(), DefaultService.class)[0];
}
or some workaround here
It's better to define a specific class for Address service
public class AddressService extends DefaultService<Address>{
public String getClassName(){
return "Address";
}
}
where
public String getClassName();
is an abstract method declared in DefaultService, and used (like your method className()) in your data access logic.
Using this approach, you will be able to add specific data access logic (example, getUsersByAddress)