I wrote a DateTimeFormatAnnotationFormatterFactory to use for global conversion of LocalDateTime, imitating LocalDateTimeFormatAnnotationFormatterFactory
package com.taimi.localdatetimedemo.format.date;
import java.time.LocalDateTime;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import org.springframework.format.AnnotationFormatterFactory;
import org.springframework.format.Formatter;
import org.springframework.format.Parser;
import org.springframework.format.Printer;
/**
* LocalDateTimeFormatAnnotationFormatterFactory
*/
public class LocalDateTimeFormatAnnotationFormatterFactory implements AnnotationFormatterFactory<LocalDateTimeFormat> {
private static final Set<Class<?>> FIELD_TYPES;
static {
Set<Class<?>> fieldTypes = new HashSet<>(1);
fieldTypes.add(LocalDateTime.class);
FIELD_TYPES = Collections.unmodifiableSet(fieldTypes);
}
#Override
public Set<Class<?>> getFieldTypes() {
return FIELD_TYPES;
}
#Override
public Printer<?> getPrinter(LocalDateTimeFormat annotation, Class<?> fieldType) {
return getFormatter(annotation, fieldType);
}
#Override
public Parser<?> getParser(LocalDateTimeFormat annotation, Class<?> fieldType) {
return getFormatter(annotation, fieldType);
}
protected Formatter<LocalDateTime> getFormatter(LocalDateTimeFormat annotation, Class<?> fieldType) {
LocalDateTimeFormater localDateTimeFormater=new LocalDateTimeFormater(annotation.pattern());
return localDateTimeFormater;
}
}
public #interface LocalDateTimeFormat {
String pattern() default "";
}
package com.taimi.localdatetimedemo.format.date;
import java.text.ParseException;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Locale;
import org.springframework.format.Formatter;
import org.springframework.util.StringUtils;
/**
* LocalDateFormater
*/
public class LocalDateTimeFormater implements Formatter<LocalDateTime> {
private String pattern;
public LocalDateTimeFormater(String pattern) {
if (StringUtils.isEmpty(pattern)) {
throw new IllegalArgumentException("Pattern can't be empty.", null);
}
this.pattern = pattern;
}
#Override
public String print(LocalDateTime localDateTime, Locale locale) {
return createDateTimeFormatter(locale).format(localDateTime);
}
#Override
public LocalDateTime parse(String text, Locale locale) throws ParseException {
return LocalDateTime.parse(text, createDateTimeFormatter(locale));
}
private DateTimeFormatter createDateTimeFormatter(Locale locale) {
return DateTimeFormatter.ofPattern(pattern, locale);
}
}
The configuration is
#Configuration
public class TimeConfig extends WebMvcConfigurationSupport {
#Override
public FormattingConversionService mvcConversionService() {
// DefaultFormattingConversionService conversionService = new DefaultFormattingConversionService(false);
FormattingConversionService conversionService=new FormattingConversionService();
conversionService.addFormatterForFieldAnnotation(new LocalDateTimeFormatAnnotationFormatterFactory());
return conversionService;
}
}
But it always failed in conversion because converterCache can not find a suitable converter or is empty.
The source code of finding converter is showing down below from GenericConversionService
#Nullable
protected GenericConverter getConverter(TypeDescriptor sourceType, TypeDescriptor targetType) {
ConverterCacheKey key = new ConverterCacheKey(sourceType, targetType);
GenericConverter converter = this.converterCache.get(key);
if (converter != null) {
return (converter != NO_MATCH ? converter : null);
}
converter = this.converters.find(sourceType, targetType);
if (converter == null) {
converter = getDefaultConverter(sourceType, targetType);
}
if (converter != null) {
this.converterCache.put(key, converter);
return converter;
}
this.converterCache.put(key, NO_MATCH);
return null;
}
I've found out where I was wrong, the #Interface should be
#Target(ElementType.FIELD)
#Retention(RetentionPolicy.RUNTIME)
public #interface LocalDateTimeFormat {
String pattern() default "";
}
It seems BeanPostProcessor interface implementation is having impact on #ServiceActivator. What should be the way to use BeanPostProcessor with #ServiceActivator. Thanks.
Complete logs are available here logs
Following is Java Config used for SFTP -
package com.ftp.example;
import java.io.File;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.batch.core.configuration.annotation.EnableBatchProcessing;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
import org.springframework.expression.common.LiteralExpression;
import org.springframework.integration.annotation.Gateway;
import org.springframework.integration.annotation.IntegrationComponentScan;
import org.springframework.integration.annotation.MessagingGateway;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.config.EnableIntegration;
import org.springframework.integration.file.FileNameGenerator;
import org.springframework.integration.file.remote.session.CachingSessionFactory;
import org.springframework.integration.file.remote.session.SessionFactory;
import org.springframework.integration.sftp.outbound.SftpMessageHandler;
import org.springframework.integration.sftp.session.DefaultSftpSessionFactory;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHandler;
import org.springframework.scheduling.annotation.EnableAsync;
import org.springframework.scheduling.annotation.EnableScheduling;
import com.jcraft.jsch.ChannelSftp.LsEntry;
#Configuration
#EnableScheduling
#EnableAspectJAutoProxy
#EnableAsync
#IntegrationComponentScan
#EnableIntegration
#EnableBatchProcessing
#PropertySource("file:C:\\DEV\\workspace_oxygen\\ftp-example\\ftp-example.properties")
public class DependencySpringConfiguration {
private Logger LOG = LoggerFactory.getLogger(DependencySpringConfiguration.class);
#Value("${project.name}")
private String applicationName;
#Value("${${project.name}.ftp.server}")
private String server;
#Value("${${project.name}.ftp.port}")
int port;
#Value("${${project.name}.ftp.username}")
private String username;
#Value("${${project.name}.ftp.password}")
private String password;
#Value("${${project.name}.ftp.remote.directory}")
private String remoteDirectory;
#Bean
public static PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer() {
return new PropertySourcesPlaceholderConfigurer();
}
#Bean
public ProcessStarter processStarter() {
return new ProcessStarter();
}
/* #Bean
public LogInjector logInjector() {
return new LogInjector();
}*/
#Bean
public FTPOutService fTPOutService() {
return new FTPOutService();
}
#Bean
public SessionFactory<LsEntry> sftpSessionFactory() {
DefaultSftpSessionFactory sf = new DefaultSftpSessionFactory();
sf.setHost(server);
sf.setPort(port);
sf.setUser(username);
sf.setPassword(password);
sf.setAllowUnknownKeys(true);
return new CachingSessionFactory<LsEntry>(sf);
}
#Bean
#ServiceActivator(inputChannel = "toSftpChannel")
public MessageHandler handler() {
SftpMessageHandler handler = new SftpMessageHandler(sftpSessionFactory());
handler.setRemoteDirectoryExpression(new LiteralExpression(remoteDirectory));
handler.setFileNameGenerator(new FileNameGenerator() {
#Override
public String generateFileName(Message<?> message) {
return "fileNameToBeFtp.txt";
}
});
return handler;
}
#MessagingGateway
public interface MyGateway {
#Gateway(requestChannel = "toSftpChannel")
void sendToSftp(File file);
}
}
And We are calling gateway object like this while doing SFTP
Main class
public class FtpExample {
public static String[] ARGS;
private static final Logger LOG = LoggerFactory.getLogger(FtpExample.class);
public static void main(String[] args) throws Exception {
ARGS = args;
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(DependencySpringConfiguration.class);
ProcessStarter processStarter = ctx.getBean(ProcessStarter.class);
processStarter.startService();
}
}
Other classes -
public class ProcessStarter {
#Inject
private FTPOutService ftpOutService;
public void startService() {
ftpOutService.ftpToBbg();
}
}
public class FTPOutService {
private static Logger log = LoggerFactory.getLogger(FTPOutService.class);
#Inject
private ApplicationContext appContext;
public void ftpToBbg() {
log.info("Starting FTP out process...");
File file = null;
try {
file = new File("C:\\Temp\\log\\debug\\ftp\\priceindex\\for-upload\\ftp-example.txt.REQ");
MyGateway gateway = appContext.getBean(MyGateway.class);
gateway.sendToSftp(file);
log.info("File {} written successfully on remote server", file);
} catch (Exception e) {
log.error("Error while uploading file {}", file, e);
}
}
}
Above code is working fine unless I am not adding following bean declaration in above defined Java Config -
public LogInjector logInjector() {
return new LogInjector();
}
Above bean definition is having following implementation -
public class LogInjector implements BeanPostProcessor {
#Override
public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
return bean;
}
#Override
public Object postProcessBeforeInitialization(final Object bean, String beanName) throws BeansException {
ReflectionUtils.doWithFields(bean.getClass(), new FieldCallback() {
#Override
public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
// make the field accessible if defined private
ReflectionUtils.makeAccessible(field);
if (field.getAnnotation(Log.class) != null) {
if (org.slf4j.Logger.class == field.getType()) {
org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(bean.getClass());
field.set(bean, log);
} else if (java.util.logging.Logger.class == field.getType()) {
java.util.logging.Logger log = java.util.logging.Logger.getLogger(bean.getClass().toString());
field.set(bean, log);
}
}
}
});
return bean;
}
}
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.FIELD)
#Documented
public #interface Log {
}
Once any BeanPostProcessor implementation is added in Java Config, it creates problem and application not able to see toSftpChannel -
org.springframework.beans.factory.NoSuchBeanDefinitionException: No
bean named 'toSftpChannel' available at
org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanDefinition(DefaultListableBeanFactory.java:685)
at
org.springframework.beans.factory.support.AbstractBeanFactory.getMergedLocalBeanDefinition(AbstractBeanFactory.java:1199)
at
org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:284)
at
org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
at
org.springframework.integration.support.channel.BeanFactoryChannelResolver.resolveDestination(BeanFactoryChannelResolver.java:88)
at
org.springframework.integration.support.channel.BeanFactoryChannelResolver.resolveDestination(BeanFactoryChannelResolver.java:45)
at
org.springframework.integration.gateway.MessagingGatewaySupport.getRequestChannel(MessagingGatewaySupport.java:327)
at
org.springframework.integration.gateway.MessagingGatewaySupport.send(MessagingGatewaySupport.java:368)
at
org.springframework.integration.gateway.GatewayProxyFactoryBean.invokeGatewayMethod(GatewayProxyFactoryBean.java:477)
at
org.springframework.integration.gateway.GatewayProxyFactoryBean.doInvoke(GatewayProxyFactoryBean.java:429)
at
org.springframework.integration.gateway.GatewayProxyFactoryBean.invoke(GatewayProxyFactoryBean.java:420)
at
org.springframework.integration.gateway.GatewayCompletableFutureProxyFactoryBean.invoke(GatewayCompletableFutureProxyFactoryBean.java:65)
at
org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at
org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213)
at com.sun.proxy.$Proxy57.sendToSftp(Unknown Source)
Looks what you have:
#Bean
public LogInjector logInjector() {
return new LogInjector();
}
If you declare BeanPostProcessors as #Bean you have to specify them with the static modifier: https://docs.spring.io/spring/docs/5.0.0.RELEASE/spring-framework-reference/core.html#beans-factorybeans-annotations
You may declare #Bean methods as static, allowing for them to be called without creating their containing configuration class as an instance. This makes particular sense when defining post-processor beans, e.g. of type BeanFactoryPostProcessor or BeanPostProcessor, since such beans will get initialized early in the container lifecycle and should avoid triggering other parts of the configuration at that point.
See the example below, I'm trying to get a Map of my TypedService beans but I would prefer if the keys were the Type enum values specified in the TypeSafeQualifier instead of the unsafe String "serviceName".
package org.test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.stereotype.Service;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import java.util.Map;
import static org.test.Application.Type.ONE;
import static org.test.Application.Type.TWO;
import static java.lang.annotation.ElementType.CONSTRUCTOR;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
#SpringBootApplication
public class Application {
#Autowired
Map<String, TypedService> works;
#Autowired
Map<Type, TypedService> fails;
public static void main(String [] args) {
SpringApplication.run(Application.class, args);
}
public enum Type {
ONE,
TWO
}
#Target({TYPE, METHOD, FIELD, CONSTRUCTOR})
#Retention(RUNTIME)
#Qualifier
public #interface TypeSafeQualifier {
Type value();
}
public interface TypedService {
void startSignup();
void activate();
}
#Service
#TypeSafeQualifier(ONE)
public class TypeOneService implements TypedService {
#Override
public void startSignup() {
}
#Override
public void activate() {
}
}
#Service
#TypeSafeQualifier(TWO)
public class TypeTwoService implements TypedService {
#Override
public void startSignup() {
}
#Override
public void activate() {
}
}
}
SpringBoot version: springBootVersion=1.5.3.RELEASE
Spring offers a special approach to handle this type of injection: AutowireCandidateResolver.
In your case the code might be:
package org.test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.config.DependencyDescriptor;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ContextAnnotationAutowireCandidateResolver;
import org.springframework.core.ResolvableType;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.stereotype.Service;
import javax.annotation.PostConstruct;
import java.lang.annotation.Annotation;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import java.util.LinkedHashMap;
import java.util.Map;
import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
#SpringBootApplication
public class Application {
#Autowired
Map<String, TypedService> works;
#Autowired
Map<Type, TypedService> fails;
#PostConstruct
private void init() {
System.out.println(fails);
}
public static void main(String[] args) {
final SpringApplication application = new SpringApplication(Application.class);
application.addInitializers(context -> {
context.addBeanFactoryPostProcessor(beanFactory -> {
final DefaultListableBeanFactory dlbf = (DefaultListableBeanFactory) beanFactory;
dlbf.setAutowireCandidateResolver(new MyAutowireCandidateResolver(dlbf));
});
});
application.run(args);
}
#QualifierValue(TypeSafeQualifier.class)
public enum Type {
ONE,
TWO
}
#Target({TYPE, METHOD, FIELD, CONSTRUCTOR})
#Retention(RUNTIME)
#Qualifier
public #interface TypeSafeQualifier {
Type value();
}
public interface TypedService {
void startSignup();
void activate();
}
#Service
#TypeSafeQualifier(Type.ONE)
public class TypeOneService implements TypedService {
#Override
public void startSignup() {
}
#Override
public void activate() {
}
}
#Target({TYPE})
#Retention(RUNTIME)
public #interface QualifierValue {
Class<? extends Annotation> value();
}
#Service
#TypeSafeQualifier(Type.TWO)
public class TypeTwoService implements TypedService {
#Override
public void startSignup() {
}
#Override
public void activate() {
}
}
private static class MyAutowireCandidateResolver extends ContextAnnotationAutowireCandidateResolver {
private final DefaultListableBeanFactory beanFactory;
private MyAutowireCandidateResolver(DefaultListableBeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
#Override
public Object getSuggestedValue(DependencyDescriptor descriptor) {
final Object result = super.getSuggestedValue(descriptor);
if (result != null) {
return result;
}
if (descriptor.getDependencyType() != Map.class) {
return null;
}
final ResolvableType dependencyGenericType = descriptor.getResolvableType().asMap();
final ResolvableType[] typeParams = dependencyGenericType.getGenerics();
final QualifierValue qualifierValue = typeParams[0].getRawClass().getAnnotation(QualifierValue.class);
if (qualifierValue == null) {
return null;
}
final String[] candidateBeanNames = beanFactory.getBeanNamesForType(typeParams[1]);
final LinkedHashMap<Object, Object> injectedMap = new LinkedHashMap<>(candidateBeanNames.length);
for (final String candidateBeanName : candidateBeanNames) {
final Annotation annotation = beanFactory.findAnnotationOnBean(candidateBeanName, qualifierValue.value());
if (annotation == null) {
continue;
}
final Map<String, Object> annotationAttributes = AnnotationUtils.getAnnotationAttributes(annotation, false);
final Object value = annotationAttributes.get("value");
if (value == null || value.getClass() != typeParams[0].getRawClass()) {
continue;
}
injectedMap.put(value, beanFactory.getBean(candidateBeanName));
}
return injectedMap;
}
}
}
First of all, we add TypeQualifierValue annotation to make Spring know about a qualifier with values of the given type.
The second is to customize the SpringApplication in the main method: we use BeanFactoryPostProcessor to set a custom AutowireCandidateResolver.
And the final step: we write MyAutowireCandidateResolver extending ContextAnnotationAutowireCandidateResolver (delegation instead of inheritance is applicable to, it's even a little bit better since one day Spring can migrate to `YetAnotherAutowireCandidateResolver' by default).
The crucial part here is the overridden getSuggestedValue method: here we can customize the injection logic considering the generic types of the dependency (field, method parameter) and by applying some getBean...-like methods from the BeanFactory with some magic of Spring AnnotationUtils class.
I have configured a RepositoryRestResource on a PageAndSortingRepository that accesses an Entity that includes a composite Id:
#Entity
#IdClass(CustomerId.class)
public class Customer {
#Id BigInteger id;
#Id int startVersion;
...
}
public class CustomerId {
BigInteger id;
int startVersion;
...
}
#RepositoryRestResource(collectionResourceRel = "customers", path = "customers", itemResourceRel = "customers/{id}_{startVersion}")
public interface CustomerRepository extends PagingAndSortingRepository<Customer, CustomerId> {}
When i access the server at "http://<server>/api/customers/1_1" for instance, I get the correct resource back as json, but the href in the _links section for self is the wrong and also the same for any other customer i query: "http://<server>/api/customer/1"
i.e.:
{
"id" : 1,
"startVersion" : 1,
...
"firstname" : "BOB",
"_links" : {
"self" : {
"href" : "http://localhost:9081/reps/api/reps/1" <-- This should be /1_1
}
}
}
I suppose this is because of my composite Id, But I am chuffed as to how i can change this default behaviour.
I've had a look at the ResourceSupport and the ResourceProcessor class but am not sure how much i need to change in order fix this issue.
Can someone who knows spring lend me a hand?
Unfortunately, all Spring Data JPA/Rest versions up to 2.1.0.RELEASE are not able to serve your need out of the box.
The source is buried inside Spring Data Commons/JPA itself. Spring Data JPA supports only Id and EmbeddedId as identifier.
Excerpt JpaPersistentPropertyImpl:
static {
// [...]
annotations = new HashSet<Class<? extends Annotation>>();
annotations.add(Id.class);
annotations.add(EmbeddedId.class);
ID_ANNOTATIONS = annotations;
}
Spring Data Commons doesn't support the notion of combined properties. It treats every property of a class independently from each other.
Of course, you can hack Spring Data Rest. But this is cumbersome, doesn't solve the problem at its heart and reduces the flexibility of the framework.
Here's the hack. This should give you an idea how to tackle your problem.
In your configuration override repositoryExporterHandlerAdapter and return a CustomPersistentEntityResourceAssemblerArgumentResolver.
Additionally, override backendIdConverterRegistry and add CustomBackendIdConverter to the list of known id converter:
import org.springframework.beans.factory.ListableBeanFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.data.rest.core.projection.ProxyProjectionFactory;
import org.springframework.data.rest.webmvc.RepositoryRestHandlerAdapter;
import org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration;
import org.springframework.data.rest.webmvc.spi.BackendIdConverter;
import org.springframework.data.rest.webmvc.support.HttpMethodHandlerMethodArgumentResolver;
import org.springframework.data.web.config.EnableSpringDataWebSupport;
import org.springframework.hateoas.ResourceProcessor;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.plugin.core.OrderAwarePluginRegistry;
import org.springframework.plugin.core.PluginRegistry;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
#Configuration
#Import(RepositoryRestMvcConfiguration.class)
#EnableSpringDataWebSupport
public class RestConfig extends RepositoryRestMvcConfiguration {
#Autowired(required = false) List<ResourceProcessor<?>> resourceProcessors = Collections.emptyList();
#Autowired
ListableBeanFactory beanFactory;
#Override
#Bean
public PluginRegistry<BackendIdConverter, Class<?>> backendIdConverterRegistry() {
List<BackendIdConverter> converters = new ArrayList<BackendIdConverter>(3);
converters.add(new CustomBackendIdConverter());
converters.add(BackendIdConverter.DefaultIdConverter.INSTANCE);
return OrderAwarePluginRegistry.create(converters);
}
#Bean
public RequestMappingHandlerAdapter repositoryExporterHandlerAdapter() {
List<HttpMessageConverter<?>> messageConverters = defaultMessageConverters();
configureHttpMessageConverters(messageConverters);
RepositoryRestHandlerAdapter handlerAdapter = new RepositoryRestHandlerAdapter(defaultMethodArgumentResolvers(),
resourceProcessors);
handlerAdapter.setMessageConverters(messageConverters);
return handlerAdapter;
}
private List<HandlerMethodArgumentResolver> defaultMethodArgumentResolvers()
{
CustomPersistentEntityResourceAssemblerArgumentResolver peraResolver = new CustomPersistentEntityResourceAssemblerArgumentResolver(
repositories(), entityLinks(), config().projectionConfiguration(), new ProxyProjectionFactory(beanFactory));
return Arrays.asList(pageableResolver(), sortResolver(), serverHttpRequestMethodArgumentResolver(),
repoRequestArgumentResolver(), persistentEntityArgumentResolver(),
resourceMetadataHandlerMethodArgumentResolver(), HttpMethodHandlerMethodArgumentResolver.INSTANCE,
peraResolver, backendIdHandlerMethodArgumentResolver());
}
}
Create CustomBackendIdConverter. This class is responsible for rendering your custom entity ids:
import org.springframework.data.rest.webmvc.spi.BackendIdConverter;
import java.io.Serializable;
public class CustomBackendIdConverter implements BackendIdConverter {
#Override
public Serializable fromRequestId(String id, Class<?> entityType) {
return id;
}
#Override
public String toRequestId(Serializable id, Class<?> entityType) {
if(entityType.equals(Customer.class)) {
Customer c = (Customer) id;
return c.getId() + "_" +c.getStartVersion();
}
return id.toString();
}
#Override
public boolean supports(Class<?> delimiter) {
return true;
}
}
CustomPersistentEntityResourceAssemblerArgumentResolver in turn should return a CustomPersistentEntityResourceAssembler:
import org.springframework.core.MethodParameter;
import org.springframework.data.repository.support.Repositories;
import org.springframework.data.rest.core.projection.ProjectionDefinitions;
import org.springframework.data.rest.core.projection.ProjectionFactory;
import org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler;
import org.springframework.data.rest.webmvc.config.PersistentEntityResourceAssemblerArgumentResolver;
import org.springframework.data.rest.webmvc.support.PersistentEntityProjector;
import org.springframework.hateoas.EntityLinks;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.ModelAndViewContainer;
public class CustomPersistentEntityResourceAssemblerArgumentResolver extends PersistentEntityResourceAssemblerArgumentResolver {
private final Repositories repositories;
private final EntityLinks entityLinks;
private final ProjectionDefinitions projectionDefinitions;
private final ProjectionFactory projectionFactory;
public CustomPersistentEntityResourceAssemblerArgumentResolver(Repositories repositories, EntityLinks entityLinks,
ProjectionDefinitions projectionDefinitions, ProjectionFactory projectionFactory) {
super(repositories, entityLinks,projectionDefinitions,projectionFactory);
this.repositories = repositories;
this.entityLinks = entityLinks;
this.projectionDefinitions = projectionDefinitions;
this.projectionFactory = projectionFactory;
}
public boolean supportsParameter(MethodParameter parameter) {
return PersistentEntityResourceAssembler.class.isAssignableFrom(parameter.getParameterType());
}
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
String projectionParameter = webRequest.getParameter(projectionDefinitions.getParameterName());
PersistentEntityProjector projector = new PersistentEntityProjector(projectionDefinitions, projectionFactory,
projectionParameter);
return new CustomPersistentEntityResourceAssembler(repositories, entityLinks, projector);
}
}
CustomPersistentEntityResourceAssembler needs to override getSelfLinkFor. As you can see entity.getIdProperty() return either id or startVersion property of your Customer class which in turn gets used to retrieve the real value with the help of a BeanWrapper. Here we are short circuit the whole framework with the use of instanceof operator. Hence your Customer class should implement Serializable for further processing.
import org.springframework.data.mapping.PersistentEntity;
import org.springframework.data.mapping.model.BeanWrapper;
import org.springframework.data.repository.support.Repositories;
import org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler;
import org.springframework.data.rest.webmvc.support.Projector;
import org.springframework.hateoas.EntityLinks;
import org.springframework.hateoas.Link;
import org.springframework.util.Assert;
public class CustomPersistentEntityResourceAssembler extends PersistentEntityResourceAssembler {
private final Repositories repositories;
private final EntityLinks entityLinks;
public CustomPersistentEntityResourceAssembler(Repositories repositories, EntityLinks entityLinks, Projector projector) {
super(repositories, entityLinks, projector);
this.repositories = repositories;
this.entityLinks = entityLinks;
}
public Link getSelfLinkFor(Object instance) {
Assert.notNull(instance, "Domain object must not be null!");
Class<? extends Object> instanceType = instance.getClass();
PersistentEntity<?, ?> entity = repositories.getPersistentEntity(instanceType);
if (entity == null) {
throw new IllegalArgumentException(String.format("Cannot create self link for %s! No persistent entity found!",
instanceType));
}
Object id;
//this is a hack for demonstration purpose. don't do this at home!
if(instance instanceof Customer) {
id = instance;
} else {
BeanWrapper<Object> wrapper = BeanWrapper.create(instance, null);
id = wrapper.getProperty(entity.getIdProperty());
}
Link resourceLink = entityLinks.linkToSingleResource(entity.getType(), id);
return new Link(resourceLink.getHref(), Link.REL_SELF);
}
}
That's it! You should see this URIs:
{
"_embedded" : {
"customers" : [ {
"name" : "test",
"_links" : {
"self" : {
"href" : "http://localhost:8080/demo/customers/1_1"
}
}
} ]
}
}
Imho, if you are working on a green field project I would suggest to ditch IdClass entirely and go with technical simple ids based on Long class. This was tested with Spring Data Rest 2.1.0.RELEASE, Spring data JPA 1.6.0.RELEASE and Spring Framework 4.0.3.RELEASE.
Although not desirable, I have worked around this issue by using an #EmbeddedId instead of a IdClass annotation on my JPA entity.
Like so:
#Entity
public class Customer {
#EmbeddedId
private CustomerId id;
...
}
public class CustomerId {
#Column(...)
BigInteger key;
#Column(...)
int startVersion;
...
}
I now see the correctly generated links 1_1 on my returned entities.
If anyone can still direct me to a solution that does not require I change the representation of my model, It would be highly appreciated. Luckily I had not progressed far in my application development for this to be of serious concern in changing, but I imagine that for others, there would be significant overhead in performing a change like this: (e.g. changing all queries that reference this model in JPQL queries).
I had a similar problem where the composite key scenarios for data rest was not working. #ksokol detailed explanation provided the necessary inputs to solve the issue. changed my pom primarily for data-rest-webmvc and data-jpa as
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-rest-webmvc</artifactId>
<version>2.2.1.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>1.7.1.RELEASE</version>
</dependency>
which solved all the issues related to composite key and I need not do the customization. Thanks ksokol for the detailed explanation.
First, create a SpringUtil to get bean from spring.
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
#Component
public class SpringUtil implements ApplicationContextAware {
private static ApplicationContext applicationContext;
#Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
if(SpringUtil.applicationContext == null) {
SpringUtil.applicationContext = applicationContext;
}
}
public static ApplicationContext getApplicationContext() {
return applicationContext;
}
public static Object getBean(String name){
return getApplicationContext().getBean(name);
}
public static <T> T getBean(Class<T> clazz){
return getApplicationContext().getBean(clazz);
}
public static <T> T getBean(String name,Class<T> clazz){
return getApplicationContext().getBean(name, clazz);
}
}
Then, implement BackendIdConverter.
import com.alibaba.fastjson.JSON;
import com.example.SpringUtil;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.rest.webmvc.spi.BackendIdConverter;
import org.springframework.stereotype.Component;
import javax.persistence.EmbeddedId;
import javax.persistence.Id;
import java.io.Serializable;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.Method;
import java.net.URLDecoder;
import java.net.URLEncoder;
#Component
public class CustomBackendIdConverter implements BackendIdConverter {
#Override
public boolean supports(Class<?> delimiter) {
return true;
}
#Override
public Serializable fromRequestId(String id, Class<?> entityType) {
if (id == null) {
return null;
}
//first decode url string
if (!id.contains(" ") && id.toUpperCase().contains("%7B")) {
try {
id = URLDecoder.decode(id, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
//deserialize json string to ID object
Object idObject = null;
for (Method method : entityType.getDeclaredMethods()) {
if (method.isAnnotationPresent(Id.class) || method.isAnnotationPresent(EmbeddedId.class)) {
idObject = JSON.parseObject(id, method.getGenericReturnType());
break;
}
}
//get dao class from spring
Object daoClass = null;
try {
daoClass = SpringUtil.getBean(Class.forName("com.example.db.dao." + entityType.getSimpleName() + "DAO"));
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
//get the entity with given primary key
JpaRepository simpleJpaRepository = (JpaRepository) daoClass;
Object entity = simpleJpaRepository.findOne((Serializable) idObject);
return (Serializable) entity;
}
#Override
public String toRequestId(Serializable id, Class<?> entityType) {
if (id == null) {
return null;
}
String jsonString = JSON.toJSONString(id);
String encodedString = "";
try {
encodedString = URLEncoder.encode(jsonString, "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return encodedString;
}
}
After that. you can do what you want.
There is a sample below.
If the entity has single property pk, you can use
localhost:8080/demo/1 as normal. According to my code, suppose the pk
has annotation "#Id".
If the entity has composed pk, suppose the pk is demoId type, and has
annotation "#EmbeddedId", you can use localhost:8080/demo/{demoId
json} to get/put/delete. And your self link will be the same.
The answers provides above are helpful, but if you need a more generic approach that would be following -
package com.pratham.persistence.config;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.sun.istack.NotNull;
import lombok.RequiredArgsConstructor;
import org.springframework.data.rest.webmvc.spi.BackendIdConverter;
import org.springframework.lang.NonNull;
import org.springframework.stereotype.Component;
import javax.persistence.EmbeddedId;
import java.io.Serializable;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.Base64;
import java.util.Optional;
import static java.nio.charset.StandardCharsets.UTF_8;
/**
* Customization of how composite ids are exposed in URIs.
* The implementation will convert the Ids marked with {#link EmbeddedId} to base64 encoded json
* in order to expose them properly within URI.
*
* #author im-pratham
*/
#Component
#RequiredArgsConstructor
public class EmbeddedBackendIdConverter implements BackendIdConverter {
private final ObjectMapper objectMapper;
#Override
public Serializable fromRequestId(String id, Class<?> entityType) {
return getFieldWithEmbeddedAnnotation(entityType)
.map(Field::getType)
.map(ret -> {
try {
String decodedId = new String(Base64.getUrlDecoder().decode(id));
return (Serializable) objectMapper.readValue(decodedId, (Class) ret);
} catch (JsonProcessingException ignored) {
return null;
}
})
.orElse(id);
}
#Override
public String toRequestId(Serializable id, Class<?> entityType) {
try {
String json = objectMapper.writeValueAsString(id);
return Base64.getUrlEncoder().encodeToString(json.getBytes(UTF_8));
} catch (JsonProcessingException ignored) {
return id.toString();
}
}
#Override
public boolean supports(#NonNull Class<?> entity) {
return isEmbeddedIdAnnotationPresent(entity);
}
private boolean isEmbeddedIdAnnotationPresent(Class<?> entity) {
return getFieldWithEmbeddedAnnotation(entity)
.isPresent();
}
#NotNull
private static Optional<Field> getFieldWithEmbeddedAnnotation(Class<?> entity) {
return Arrays.stream(entity.getDeclaredFields())
.filter(method -> method.isAnnotationPresent(EmbeddedId.class))
.findFirst();
}
}
all.
i am a newbie of lucene, and i'm using spring-mvc (3.2.5.RELEASE) and lucene(4.6.0).
both are newest version currently.
how can i use NEAR REAL TIME search?
i write this code to get instance of IndexWriter (sington)
package com.github.yingzhuo.mycar.search;
import java.io.IOException;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.io.Resource;
import org.springframework.util.Assert;
import org.wltea.analyzer.lucene.IKAnalyzer;
public class IndexWriterFactoryBean implements FactoryBean<IndexWriter>, InitializingBean, DisposableBean {
private static final Logger LOGGER = LoggerFactory.getLogger(IndexWriterFactoryBean.class);
private Analyzer analyzer = new IKAnalyzer(false);
private Resource indexDirectory = null;
private IndexWriter indexWriter = null;
private Directory directory = null;
public IndexWriterFactoryBean() {
if (indexDirectory != null) {
try {
if (! indexDirectory.getFile().exists()) {
FileUtils.forceMkdir(indexDirectory.getFile());
}
} catch (IOException e) {
LOGGER.warn(e.getMessage(), e);
}
}
}
#Override
public IndexWriter getObject() throws Exception {
return indexWriter;
}
#Override
public Class<?> getObjectType() {
return IndexWriter.class;
}
#Override
public boolean isSingleton() {
return true;
}
#Override
public void afterPropertiesSet() throws Exception {
Assert.notNull(analyzer, "property 'analyzer' must be set.");
Assert.notNull(indexDirectory, "property 'indexDirectory' must be set.");
directory = FSDirectory.open(indexDirectory.getFile());
indexWriter = new IndexWriter(directory, new IndexWriterConfig(Version.LUCENE_46, analyzer));
}
#Override
public void destroy() throws Exception {
IOUtils.closeQuietly(indexWriter);
IOUtils.closeQuietly(directory);
IOUtils.closeQuietly(analyzer);
}
// getter & setter
// ------------------------------------------------------------------------------------------
public void setAnalyzer(Analyzer analyzer) {
this.analyzer = analyzer;
}
public void setIndexDirectory(Resource indexDirectory) {
this.indexDirectory = indexDirectory;
}
}
and this utility to get DirectoryReader by static method.
import java.io.IOException;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import com.github.yingzhuo.mycar.config.SpringUtils;
public final class DirectoryReaderHolder {
private static DirectoryReader HOLDER = null;
public synchronized static DirectoryReader get() {
if (HOLDER == null) {
try {
HOLDER = DirectoryReader.open(SpringUtils.getBean(IndexWriter.class), true);
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
return HOLDER;
}
public static synchronized void set(DirectoryReader directoryReader) {
if (directoryReader == null) {
throw new NullPointerException();
} else {
HOLDER = directoryReader;
}
}
}
and this bean to inject into my spring-mvc controller. In 'create' method, i am trying to get a new reader before i create a IndexSearcher, but HOW SHOULD I HANDLE THE OLD READER ?
can i close it directly? if other threads are still using the old reader, very bad thing will happen ?
package com.github.yingzhuo.mycar.search;
import java.io.IOException;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.search.IndexSearcher;
public class IndexSearcherManager {
public IndexSearcher create() {
try {
DirectoryReader oldReader = DirectoryReaderHolder.get();
DirectoryReader newReader = DirectoryReader.openIfChanged(oldReader);
if (newReader != null) {
oldReader.close(); // AM I RIGHT ???
oldReader = newReader;
}
return new IndexSearcher(oldReader);
} catch (IOException e) {
throw new IllegalStateException(e);
}
}
}
Any suggestions? thank you.