找不到能够从java.lang.String类型转换为类型@ org.springframework.data.repository.query.Param的转换器
问题描述:
我正在用spring boot 1.1.5构建一个MongoDb rest应用程序。我创建了一个信息库:找不到能够从java.lang.String类型转换为类型@ org.springframework.data.repository.query.Param的转换器
@RepositoryRestResource(collectionResourceRel = "SourceProductV1Repository", path = "SourceProductV1Repository")
public interface SourceProductV1Repository extends MongoRepository<SourceProductV1Model, String> {
public List<SourceProductV1Model> findByUser (@Param("user") MongoUser user);
}
我定义了一个转换器,以字符串转换为MongoUser(转换器在Spring上下文正确注册):
@Component
public class String2MongoUserConverter implements Converter<String, MongoUser>{
private static final Log LOGGER = LogFactory.getLog(String2MongoUserConverter.class.getName());
@Override
public MongoUser convert(String s) {
return null;
}
}
所以,当我尝试访问http://localhost:8080/SourceProductV1Repository/search/findByUser?user=test
我得到以下错误:
org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type java.lang.String to type @org.springframework.data.repository.query.Param com.ddelizia.model.MongoUser
at org.springframework.core.convert.support.GenericConversionService.handleConverterNotFound(GenericConversionService.java:291)
at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:177)
at org.springframework.data.rest.core.invoke.ReflectionRepositoryInvoker.prepareParameters(ReflectionRepositoryInvoker.java:265)
at org.springframework.data.rest.core.invoke.ReflectionRepositoryInvoker.invokeQueryMethod(ReflectionRepositoryInvoker.java:230)
at org.springframework.data.rest.webmvc.RepositorySearchController.executeQueryMethod(RepositorySearchController.java:236)
at org.springframework.data.rest.webmvc.RepositorySearchController.executeSearch(RepositorySearchController.java:146)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:749)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:689)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:938)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:870)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
)
我做错了什么?也许它在转换器中期待某种其他类型的目标?
答
我固定在下面的方式创建豆:许多尝试
@Configuration
public class MongoConvertersConfiguration {
@Resource(name = "defaultConversionService")
private GenericConversionService genericConversionService;
@Bean
public String2MongoUserConverter string2MongoUserConverter(){
String2MongoUserConverter string2MongoUserConverter = new String2MongoUserConverter();
genericConversionService.addConverter(string2MongoUserConverter);
return string2MongoUserConverter;
}
}
+0
嗨,你可以请张贴的String2MongoUserConverter定义片段 – Shiva 2018-01-10 04:53:01
答
后,我找到了这个解决方案
@PostConstruct
public void init(){
GenericConversionService conversionService = (GenericConversionService) DefaultConversionService.getSharedInstance();
conversionService.addConverter(new JPAConverter());
}
转换器和GenericConvert支持。
你确定转换器是否正确注册?你如何注册转换器?为什么转换器有一个'@ Repository'注释? – Jesper 2014-09-03 06:53:10
这是我的错误..无论如何,我注册为'@组件'(我打印所有实例化的豆,我看到正在运行),但我得到了同样的错误..可以是'@参数'anotation(我使用Java 7) – ddelizia 2014-09-03 07:54:29
我不认为只在应用程序上下文中注册转换器就足够了。查看文档:[使用自定义转换器覆盖默认映射](http://docs.spring.io/spring-data/data-mongo/docs/current/reference/html/mongo.core.html#mongo.custom-converters ) – Jesper 2014-09-03 09:05:35